An-Najah National University Faculty of Graduate Studies Environmental Impact Assessment of Centralized and Decentralized Biogas Power Plants in Palestine By Ruba Ahmad Hasan Alia Supervisor Dr. Abdelrahim Abusafa Co-Supervisor Prof. Amer El-Hamouz This Thesis is Submitted in Partial Fulfillment of the Requirement for the Degree of Master of Clean Energy and Conservation Strategy Engineering, Faculty of Graduate Studies An-Najah National University, Nablus, Palestine 2017 II Environmental Impact Assessment of Centralized and Decentralized Biogas Power Plants in Palestine By Ruba Ahmad Hasan Alia This thesis was defended successfully on 31/01 /2017 and approved by: Defense committee Members Signature  Dr. Abdelrahim Abusafa/Supervisor .…..………….…..  Prof. Amer El-Hamouz/Co-Supervisor ……………...……  Dr. Mahmoud Salah /External Examiner ………………...…  Dr. Husni Odeh /Internal Examiner ………………...… III Dedication To my parents To my husband To my daughter To my brother and sister To my family To all friends and colleagues To all of them I dedicate this work IV Acknowledgment I would like to take the opportunity to thank all people who spent their time and shared their knowledge for helping me to complete my thesis with the best possible result. To begin with, my special thanks to Dr. Abdelrahim Abusafa, direct supervisor for his continued support, complete cooperation and distinguish supervision throughout the whole course of this study. I wish to express my gratitude to my Prof. Amer El- Hamouz who participated as the second supervisor of this study for his valuable suggestions, assistance, and for his great and continuous effort in helping me at all stages of this study. My thanks and appreciations go also to the staff of Clean Energy and Conservation Strategy Engineering master program at An- Najah National University. Finally, I must express my very profound gratitude to my parents and to my husband, brothers ,sisters , kindred,and all friend for providing me with unfailing support and continuous encouragement throughout my years of study and through the process of researching and writing this thesis. This accomplishment would not have been possible without them. Thank you V اإلقرار أنا الموقع أدناه مقدم الرسالة التي تحمل العنوان Environmental Impact Assessment of Centralized and Decentralized Biogas Power Plants in Palestine Declaration The work provided in this thesis, unless otherwise referenced, is the researcher's own work, and has not been submitted elsewhere for any other degrees or qualifications. Student's Name: Signature: Date: VI Table of Contents Dedication ................................................................................................... III Acknowledgment ........................................................................................ IV Declaration ................................................................................................... V Table of Contents ........................................................................................ VI List of Figures ............................................................................................. IX List of Tables ................................................................................................ X List of symbols .......................................................................................... XII List of abbreviations ................................................................................. XIII Palestinian Central Bureau of Statistics ................................................ XIII Abstract .................................................................................................... XIV Chapter One ................................................................................................... 1 Introduction ................................................................................................... 1 Chapter Two .................................................................................................. 4 Biomass Technology ..................................................................................... 4 2.1 Introduction ....................................................................................... 5 2. 2 Biogas Technology History ............................................................. 5 2.3 Composition of Biogas ..................................................................... 7 2.4 Biogas Production: ............................................................................ 8 2.4.1 The Stages of Anaerobic Digestion .................................................. 9 2.4.2 Factors Affecting Anaerobic Degradation: ..................................... 11 2.4.2.2 Temperature ................................................................................. 11 2.4.2.4 Retention Time ............................................................................. 12 2.5 Types of Biomass ............................................................................ 14 2.5.1 Animal Waste .................................................................................. 14 2.5.2 Wood and Agriculture Products ..................................................... 14 2.5.3 Municipal Solid Waste .................................................................... 15 2.6 Advantages of Using Biomass: ....................................................... 15 2.7 Design of Biogas Plant: .................................................................. 16 2.8 Biogas - Digester types ................................................................... 17 2.9 Applications of Biogas in Household Digesters ............................. 20 2.9.1 Cooking and Heating ...................................................................... 20 2.9.2 Biogas Stoves .................................................................................. 20 2.9.4 Lighting and Power Generation ...................................................... 20 Chapter Three .............................................................................................. 21 Methodology ............................................................................................... 22 3.1 Data Collection of Raw Materials ................................................ 23 3.2 Animal Waste Calculation ............................................................. 23 3.3 Biogas Volume Calculation: ........................................................... 24 3.4 Calculation of energy potential: ...................................................... 24 3.5 Sizing the Plant ............................................................................... 25 VII 3.5.1 Sizing the digester ........................................................................... 25 3.6 Cost of Plant .................................................................................... 25 3.6.1 Digester cost .................................................................................... 25 3.6.2 Generator Cost: ............................................................................... 26 3.7 Annual Cost Calculation ................................................................. 26 3.8 Clustering of Power plant ............................................................... 27 3.9 Transportation Cost ......................................................................... 27 3.10 Payback Period Calculation .......................................................... 28 3.11 Environmental Impact Assessment ............................................... 28 Chapter Four ................................................................................................ 29 Environmental Impact Assessment of Establishing Biogas Plant .............. 29 4.1 Definition of EIA ............................................................................ 30 4.1.1 Project description, and legal and administrative framework: ....... 31 4.1.2 Screening ......................................................................................... 32 4.1.3 Description of the existing environment: ....................................... 32 4.1.4 Scoping ............................................................................................ 32 4.1.5 Mitigating measures: .................................................................... 33 4.1.6 Environmental management and training and environmental monitoring plan: ............................................................................. 33 4.2 Policy and Legal Framework .......................................................... 33 4.2.1 Environmental Assessment Policy .................................................. 34 4.3 EIA type methods .................................................................................. 35 4.3.1 Construction of Leopold Matrix for Centralized and Decentralized Biogas Power Plant ........................................................................ 36 4.4 Environmental Aspects, Impacts and Mitigation ............................ 38 4.5 CO2 Reduction Potential with Biogas Production ................................ 45 Chapter Five ................................................................................................ 46 Results and Discussion ................................................................................ 46 5.1 Animals Waste in Palestine ............................................................ 47 5.2 Potential of Biogas Production ....................................................... 51 5.3 Electrical Energy Production .......................................................... 53 5.4 Sizing the Digester .......................................................................... 55 5.5 Analysis Cost of Biogas Plant......................................................... 57 5.6 Equivalent Annual Cost Calculation ............................................... 59 5.7 Decentralized and Centralized Power Plant.................................... 63 5.7.1 Proposed Decentralized Biogas Plant for Tubas Governorate ....... 63 5.7.2 Proposed Centralized Biogas Plant for Tubas Governorate ........... 66 5.8 Comparison of Cost between the Proposed Centralized and Decentralized Biogas Plant .......................................................... 73 5.9 The Percentage of Waste which can be used in Centralized Plant . 74 5.10 Summary of Proposed Centralized Biogas Power Plants for All Governorates ................................................................................ 75 VIII 5.10.1Proposed Centralized Biogas Power Plants for Hebron governorate75 5.10.2 Proposed Centralized Biogas Power Plants for Bethlehem Governorate .................................................................................... 78 5.10.3Proposed Centralized Biogas Power Plants for Jericho Governorate ........................................................................................................ 80 5.10.4 Proposed Centralized Biogas Power Plants for Ramallah Governorate .................................................................................. 83 5.10.5 Proposed Centralized Biogas Power Plants for Nablus Governorate ........................................................................................................ 86 5.10.6 Proposed Centralized Biogas Power Plants for Qalqilya Governorate ........................................................................................................ 89 5.10.7 Proposed Centralized Biogas Power Plants for jenin Governorate91 5.10.8 Proposed Centralized Biogas Power Plants for Tulkarem Governorate .................................................................................... 94 5.10.9 Proposed Decentralized Biogas Power Plants Salfeet Governorate97 Chapter six ................................................................................................... 98 Conclusions and recommendations ............................................................. 98 6.1 Conclusions ..................................................................................... 99 6.2 Recommendations: ........................................................................ 101 References ................................................................................................. 103 Appendix A ............................................................................................... 109 Appendix B ............................................................................................... 113 Appendix C ............................................................................................... 116 Appendix D ............................................................................................... 118 Appendix E ................................................................................................ 122 Appendix F ................................................................................................ 126 Appendix G ............................................................................................... 129 Appendix H ............................................................................................... 134 Appendix I ................................................................................................. 137 Appendix J ................................................................................................. 139 ب ........................................................................................................... الملخص IX List of Figures Figure (2. 1): Use of anaerobic digestion per million inhabitants in European countries for year of 2006 ..................................................... 7 Figure (2. 2): biogas production process...................................................... 8 Figure (2. 3): Schematic representation of the sustainable cycle of naerobic co-digestion of animal manure and organic wastes .............. 9 Figure (2. 4): The Stages of Anaerobic Digestion ..................................... 10 Figure (2. 5): Biogas productions after addition of substrate .................... 12 Figure (2. 6): Type of biomass ................................................................... 15 Figure (2. 7): Biogas schematic diagram of biogas digester ..................... 17 Figure (3. 1): Research Methodology Diagram ......................................... 22 Figure (4. 1): Generalized EIA Process Flow-Chart [33] .............................................................. 31 Figure (5. 1): The relationship between volume and cost of produced electrical energy (NIS/kWh)………...……………………63 Figure (5. 2): proposed decentralized biogas Plant for Tubas Governorate ............................................................................................. 64 Figure (5. 3): The main proposed clusters in Tubas Governorate ............. 67 Figure (5. 4): Proposed Centralized biogas plant for Hebron governorate 76 Figure (5. 5): Proposed Centralized biogas power plant for Bethlehem Governorate ........................................................................ 80 Figure (5. 6): Proposed Centralized biogas power plant for Jericho Governorate ........................................................................ 82 Figure (5. 7): Proposed Centralized biogas power plant for Ramallah Governorate ........................................................................ 85 Figure (5. 8): Proposed Centralized biogas power plant for Nablus Governorate ........................................................................ 88 Figure (5. 9): Proposed Centralized biogas power plant for Qalqulia Governorate ........................................................................ 91 Figure (5. 10): ProposedCentralized biogas power plant for Jenin Governorate ........................................................................ 93 Figure (5. 11): ProposedCentralized biogas power plant for Tulkarem Governorate ........................................................................ 96 Figure (5. 12): Proposed Centralized biogas power plantfor salfeet Governorate ........................................................................ 97 file:///E:/Medad/Master/ربا%20عليا/final%20thesis%20(ruba).docx%23_Toc469453813 file:///E:/Medad/Master/ربا%20عليا/final%20thesis%20(ruba).docx%23_Toc469453814 file:///E:/Medad/Master/ربا%20عليا/final%20thesis%20(ruba).docx%23_Toc469453814 file:///E:/Medad/Master/ربا%20عليا/final%20thesis%20(ruba).docx%23_Toc469453816 file:///E:/Medad/Master/ربا%20عليا/final%20thesis%20(ruba).docx%23_Toc469453816 X List of Tables Table (2. 1): Composition of Biogas .............................................................. 8 Table (2. 2): C/N Ratio of some organic materials ........................................ 14 Table (2. 3): The types of digester ................................................................. 18 Table (3. 1): Amount of animals and poultry waste production…........... ....23 Table (3. 2): Amount and percent of biogas yield form waste of animals and poultry. ..................................................................................... 24 Table (3. 3): parameters for energy calculation ............................................ 24 Table (4. 1): Leopold matrix for centralized biogas power plant………… ..37 Table (4. 2): leopold matrix for decentralized biogas power plant ................ 38 Table (4. 3): the different impact types in the construction and operational phases ....................................................................................... 39 Table (5. 1): amounts of animal waste in Tubas Governorate …..………....49 Table (5. 2): annual amounts of animal waste for all Governorates .............. 51 Table (5. 3): The Potential of Biogas Production for Tubas Governorates ... 52 Table (5. 4): The Potential of Biogas Production for all Governorates ......... 53 Table (5. 5): The annual electrical energy potential production in Tubas Governorate .............................................................................. 54 Table (5. 6): calculated sizes of digesters for Tubas Governorate ................. 56 Table (5. 7): Electricity sizes of digester for all Governorates ...................... 57 Table (5. 8): Total cost of proposed biogas power plant for Tubas Governorate………………………………………………… . 58 Table (5. 9): Total cost of biogas power plant for all Governorates .............. 59 Table (5. 10): The equivalent annual cost for proposed biogas plants for Tubas Governorate .............................................................................. 60 Table (5. 11): The equivalent annual cost for proposed biogas plants for all Governorates ............................................................................ 61 Table (5. 12): The cost of one kWh for proposed biogas plants for Tubas governorate ............................................................................... 62 Table (5. 13): P.B.P of Proposed Decentralized biogas power plant for Tubas Governorate .............................................................................. 65 Table (5. 14): calculation for first cluster (group 1) in proposed centralized biogas power plant for Tubas Governorate .............................. 70 Table (5. 15): calculation for second cluster (group 2) in proposed centralized biogas power plant for Tubas Governorate .............................. 71 Table (5. 16): calculation for third cluster (group 3) in proposed centralized biogas power plant for Tubas Governorate .............................. 72 Table (5. 17): Summary of proposed centralized biogas power plant for Tubas Governorate .............................................................................. 73 Table (5. 18):P.B.P of proposed centralized and decentralized biogas plants for Tubas Governorate ................................................................... 74 Table (5. 19): The Percentage of waste used in proposed centralized plant .. 74 XI Table (5. 20): Size and economical summary of proposed centralized biogas plants for Hebron Governorate plant ....................................... 77 Table (5. 21): Size and economical summary of proposed centralized biogas plants for Bethlehem Governorate ........................................... 79 Table (5. 22): Size and economical summary of proposed centralized biogas plants for Jericho Governorate ................................................. 81 Table (5. 23): Size and economical summary of proposed centralized biogas plants for Ramallah Governorate ............................................. 84 Table (5. 24): Size and economical summary of proposed centralized biogas plants for Nablus Governorate ................................................. 87 Table (5. 25): Size and economical summary of proposed centralized biogas plants for Qalqulia Governorate ............................................... 90 Table (5. 26): Size and economical summary of proposed centralized biogas plants for jenin governorate ..................................................... 92 Table (5. 27): Size and economical summary of proposed centralized biogas plants for Tulkarem Governorate ............................................. 95 XII List of symbols € Euro = 4.2 NIS C Cost (NIS) CV calorific value (MJ/m3) D Distance (km) E Electrical Energy (kWh) i Annual interest rate (% /year) n project estimated useful life [years] P Power (kW) T Temperature (°C) Vd Volume of digester (m3) Vg Volume of biogas W Wight (kg) η Efficiency XIII List of abbreviations AW Annual Worth AWt Annual Worth with transportation CH4 Methane CO2 Carbon dioxide EIA Environmental Impact Assessment DM Dry Matter EQA Environmental Quality Authority HRT Hydraulic Retention Time IEC Israel Electric Corporation JSC Joint Service Council Regulations kWh Kilo watt hour LPG Liquid petroleum gas MOA Ministry of Agriculture MOH Ministry of Health NEAP National Environmental Action Plan MT Metric Ton O&M Operation and maintenance PA Palestinian Authority OTS Organic (volatile) of total solid PCBS Palestinian Central Bureau of Statistics PEAP Palestinian Environmental Assessment Policy PH power of hydrogen (acidity degree value ) PLC Palestinian legislative council PW Present Worth PWA Palestinian Water Authority PWL Palestinian Labor Ministry RT Retention time P.B.P payback period Sd daily substrate input rate , TS Total Solid VFAs Volatile fatty acids http://www.pcbs.gov.ps/ XIV Environmental Impact Assessment of Centralized and Decentralized Biogas Power Plants in Palestine By Ruba Ahmad Hasan Alia Supervisor Dr. Abdelrahim Abusafa Co- Supervisor Prof. Amer El-Hamouz Abstract Biogas production by biodigestion is considered as an important method for the production of renewable energy. One of the most important methods in utilization biogas is the production of electrical energy by means of special generators. In West Bank, there are a lot of animals such as cattle, goats, sheep and poultry. These animals produce a huge amount of dung which can be anaerobically digested and produces what is called biogas. In order to estimate the amount of electrical energy that can be generated from biogas produced by the biodigestion of animal dung, many statistical data were collected according to the type and number of animals and the mass of daily manure production. This was done for most villages in ten governorates in West Bank. This research is aimed at studying the economic feasibility and environmental impact assessment for electrical energy production from biogas plants. After the calculation of annual waste production in each village, the biodigester volume, the capacity of electrical generator and the potential of production electrical energy were calculated. Consequently, Annual Worth (AW) was calculated. Moreover, the Levelized Cost of Energy (LCoE) was calculated. For profitable and environmentally friendly production, the selling price for one kWh of electricity is considered to be 0.3 NIS in order to compete with Israel electrical company which sells electricity for local electricity distribution companies by 0.4 NIS /kWh. XV To guarantee short payback period, it was found that biodigesters of volume less than 100m3 were infeasible. Since the levelized cost of energy depends directly on the volume of the biodigeter, the design of centralized biogas stations were investigated. The proposed methods depends on collecting the manure from all nearby villages and construct a single centralized biodigester for each clusters at one of the villages taking in consideration the environmental impacts and the feasibility. It was obvious that all of proposed centralized biogas power plant is feasible from economical aspects with shorter payback period than decentralized biogas power plant. It was also found that from environmental impact assessment that centralized biogas power plant is better from social and environmental aspects. Based on the results of this study, it was found that the proposed Hebron governorate biogas power plant has the largest amount of biogas production from all governorates, which has 45,670 m3 daily biogas production that is equivalent to annual electrical energy of 28.8GWh. The least biogas production was found to be in Salfeet governorate, with a daily biogas production of 2,860 m3 which is equivalent to annual electrical energy of 2GWh. Potential electrical energy production is estimated to be 2% of total energy consumption in west bank. In the case of proper utilization of these bioenergy sources, it is expected to minimize the amount of green house emissions equivalent to 100,000 ton CO2 which may produced from the same amount from the production of electrical energy from coal. 1 Chapter One Introduction 2 Chapter One Introduction Energy is one of the most important factors to global prosperity. The dependence on fossil fuels as primary energy source has lead to global climate change, environmental degradation, human health problems, and infrastructure problems. Moreover, the recent rise in oil and natural gas prices leads to search for alternative energy sources such as renewable energy. Renewable energy has different types and can be found in different forms, for instance, wind energy, solar energy, hydroelectric energy, biomass energy. But we have problems with the availability of wind and water in Palestine, and the high cost of solar energy, therefore these sources are not available in Palestine. Redundant biomass can be considered a good source of producing energy usage, this biomass can reduce the volume of generated wastes that should be disposed off with more positive impacts on our health, economy and our environment in general. Biogas production in Palestine is still not mature as biogas technology application started in from some rural areas, these initiatives are carried out on family level where animals and agricultural wastes are available. One of the problems facing biomass energy production is that biomass waste spread all over the country and also the high cost of building power plants [1]. . 3 Additionally and according to Palestinian Environmental Quality Authority (EQA), construction of biogas power plant required an environmental impact assessment. In this thesis, theoretical study of the use of manure from animals waste to produce electrical using biogas digesters will be studied. The environmental impacts of producing electricity from all exiting animal farms in all Palestinian governorates were studied in terms economy and environmentally. Centralized and decentralized biogas digester plant concepts were used. The main objectives for this research are:  Collect necessary data related the number of animals and amount of animals waste.  Calculate the biogas and possible energy production rates.  Calculate the volume of digester and apply cost analysis of biogas plants for both centralized and decentralized plants.  Perform or brief Environmental Impact Assessment for the construction of biogas plants. 4 Chapter Two Biomass Technology 5 Chapter Two Biomass Technology 2.1 Introduction The biomass resource can be considered as organic matter, in which the energy of sunlight is stored in chemical bonds. When the bonds between adjacent carbon, hydrogen and oxygen molecules are broken by digestion, combustion, or decomposition, these substances release their stored, chemical energy. Biomass has always been a major source of energy for mankind and is presently estimated to contribute of the order 10–14% of the world’s energy supply [2]. 2. 2 Biogas Technology History Evidence of biogas-use can be found in ancient civilizations. Anecdotal evidence indicates that biogas was used for heating bath water in Assyria during the 10th century BC. Marco Polo, in the 13th century AD, discovered people in China using covered sewage tanks to generate heat. In the 17th century, Jan Baptita Van Helmont determined that decaying organic matter produced flammable gas. Additionally, in 1808 Sir Humphrey Davy discovered that methane was present in the gases produced in cattle manure piles [3]. . In Arab countries the applying of biogas plants started in 1970s in Egypt, Morocco, Sudan and Algeria while it began in 1980s in other Asian Arab countries as Iraq, Jordan and Yemen In Egypt there were 18 family biogas plants and 2 farm plants built in 1998 . Palestine has different types of plant 6 products that can be used as energy sources. The main type of these products is the reject of olive oil pressers waste called jefit which is used in household for heating in winter. Another more important energy material is animal dung [4]. The number of biogas plants in Arab countries is very small in compared with other countries. For example; digesters spreading vital heavily in China and approached the 4.5 million digesters, China has the largest biogas program in the world. Then India came second with a total of 200000 digesters [5]. According to the California Energy Commission web site, California produces about 60 million tons of biomass in 2006, which means around 2000MW of electrical power [6]. In the USA, Canada, and Western Europe anaerobic digestion has been used mainly for processing animal manure till the mid-1970s. The advancements in high rate anaerobic digesters began with the introduction of anaerobic filter in 1967. The use of anaerobic digestion per million inhabitants in European countries in 2006 is shown in figure (2.1) [7]. . 7 Figure (2. 1): Use of anaerobic digestion per million inhabitants in European countries for year of 2006 [6] 2.3 Composition of Biogas Biogas technology is about capturing the gas that results from the aerobic fermentation of biomass. The plant uses the natural processes of anaerobic digestion to produce biogas to produce biogas from animal waste. Biogas is a mixture of gas produced by methanogenic. Bacteria while acting upon biodegradable materials in an anaerobic condition. Biogas is a flammable gas produced by microbes when organic materials are fermented in a certain range of temperature and moisture content. Biogas is about 20% lighter than air and has ignition temperature in the range of 650 to 750 Co. It is odorless and colorless gas that burns with clear blue flame similar to that of LPG gas. Naturally occurring bacteria (methanogenic bacteria) produce biogas during digestion or fermentation of organic matter in the absence of oxygen (anaerobic process). The produced gas consists mainly of methane (CH4) and 8 carbon dioxide (CO2). There are also traces of water vapor, hydrogen, nitrogen and hydrogen sulphide. Biogas is combustible if the methane content is more than 50%, Biogas from animal dung contains approximately 60% methane. Composition of Biogas is shown in Table (2.1). Table (2. 1): Composition of Biogas [8, 9] Composition of Biogas Gases Symbol Percentage (%) Gross Heating Value (kJ/kg) Methane CH4 50-70 55,510 Carbon dioxide CO2 25-30 0 Hydrogen H2 5-10 141,780 Nitrogen N2 1-2 0 Water vapor H2O 0.3 0 2.4 Biogas Production: To ensure continuous gas production, the biogas plants shown schematically in Figure (2.2) must be fed daily with an ample supply of substrate, preferably in liquid and chopped or crushed form. The slurry is fed into the digester by way of the mixing pit [8] . Figure (2. 2): biogas production process [8] http://www.engineeringtoolbox.com/gross-net-heating-value-d_824.html 9 If possible, the mixing pit should be directly connected to the livestock housing by a manure gutter, in figure (2.3), the Schematic representation of the sustainable cycle of anaerobic co-digestion of animal manure and organic wastes. Carbon dioxide in the atmosphere is taken up by plants and converted, using solar energy through the process of photosynthesis, into organic compounds. Some of these organic compounds are then used as food by herbivores and humans, whose respiration returns CO2 to the atmosphere. CO2 is also returned to the atmosphere when carbon compounds are burned as fuel. Fossil fuels were formed as a result of photosynthesis millions of years ago. Figure (2. 3): Schematic representation of the sustainable cycle of anaerobic co-digestion of animal manure and organic wastes [10] 2.4.1 The Stages of Anaerobic Digestion Anaerobic digestion consists of four stages: 10  Hydrolysis: Enzymes break down and liquefy the smaller molecules and break down large polymers in the material.  Acidogenesis: The products of the hydrolysis (soluble monomers) are fermented to volatile fatty acids (or VFAs) and alcohols.  Acetogenesis: During the acetogenesis acetate is created from carbon and energy sources by acetogens. Acetogens splits biomass so that it could be used in methanogenesis process to create methane.  Methanogenesis: the methanogenic bacteria convert acetic acid and hydrogen into CO2 and methane. These stages need to be managed early on in starting a digester, but if the process is properly maintained, methane production should require a minimum of chemical testing and treatment. Bacteria must do their work in the earlier stages to use up the oxygen in the material, and then break it down into volatile fatty acids and fermented alcohols, before the methanogenic bacteria can start to make methane, A schematic representation of these stages is shown in Figure (2.4) [11]. Figure (2. 4): The Stages of Anaerobic Digestion [12] 11 2.4.2 Factors Affecting Anaerobic Degradation: There are several factors which may affect the anaerobic degradation of biodegradable materials. A short description of each is followed 2.4.1.1 PH Value The pH of the digester is a function of the concentration of volatile fatty acids produced, bicarbonate alkalinity of the system, and the amount of carbon dioxide produced. The optimum range of pH for biogas production is between 7.0 and 7.2. But the substantial biogas can be produced for the pH range of 6.6 to 7.6. Biogas production reduces many fold for the pH value of less than 5 as the bacteria Population decrease significantly under the circumstances. [13]. 2.4.2.2 Temperature Temperature has the most pronounced impacts on anaerobic digestion. It has three main temperature ranges: from 10-25°C (psychrophilic conditions), from 30-37°C (mesophilic conditions) and from 48-55°C (thermophilic conditions). Psychrophilic digestion process is very slow hence only mesophilic and thermophilic digestion processes are used in practice. At very low or high temperature the activities of bacteria population is almost stopped consequently the digestion process becomes very long. Hence the production of biogas is reduced. The methane content becomes very low [13]. 12 2.4.2.3 Loading Rate The amount of raw materials fed per unit volume of digester or capacity per day is known as loading rate. It is important to optimize the loading rate in order to avoid overfeeding which leads to inhibited methane production. However, underfeeding the plant would lead to low gas production and economically ineffective process as well [10]. 2.4.2.4 Retention Time Hydraulic Retention Time (HRT) is also known as hydraulic residence is the time required for complete digestion time of the substrates in Digester as shown in figure (2.5). Hydraulic retention time is the volume of the digester divided by the influent flow rate. HRT = Volume of Digester / Influent Flow Rate where using (SI Units) Volume is in [m3] and Influent flow rate is in [m3 /h]. HRT is usually expressed in hours (or sometimes days). Therefore, the appropriate retention time is determined due to careful consideration of process temperature and substrate type [14]. Figure (2. 5): Biogas productions after addition of substrate [14] 13 2.4.2.5 Toxicity Some of the toxic materials that might inhibit the normal growth of pathogens in the digester include mineral ions, heavy metals and detergents. However, low concentrations of the mineral ions, such as sodium, potassium, calcium, magnesium, ammonium and sulphur, are needed for stimulation of bacterial growth. At the same time, if the concentration of these ions were too high, it would lead to toxification. Addition of substances including soap, antibiotics, organic solvents, etc should be avoided, since this would lead to inhibition of the activity of methane producing bacteria [10]. 2.4.2.6 Available Nutrients Apart from providing a source of carbon and energy through organic substances for the bacteria to be able to grow, they require other mineral nutrients as well. Except from carbon, oxygen and nitrogen for the production of biomass a sufficient amount of nitrogen, sulphur, phosphorous, potassium, calcium, magnesium and a little amount of trace elements such as manganese, molybdenum, cobalt, zinc, selenium and nickel etc are also needed. [10]. 2.4.2.7 C/N Ratio Both nitrogen and carbon is essential for microorganisms in order to assimilate these into their cell structure. Based on studies, the metabolic activity of methanogenic bacteria is possible to be optimized at a C/N ratio around 20-30. However, depending on the characteristics of the substrate, 14 the optimum point can vary, C/N Ratio is for different animal wastes is given in Table (2.2) [15]. Table (2. 2): C/N Ratio of some organic materials [15] Raw materials C/N Ratio Duck dung 8 Human excreta 8 Chicken dung 10 Pig dung 18 Sheep dung 19 Goat dung 12 Water hyacinth 25 Cow dung/ Buffalo dung 24 2.5 Types of Biomass 2.5.1 Animal Waste Beef cattle, dairy cattle, hogs, and poultry all produce manure, which can be used to produce energy. Manure is typically categorized as liquid, slurry, or solid. In its solid state, manure can be burned for heating and cooking or to produce a gas for energy production. As a slurry, manure releases methane (CH4), which can be captured to produce heat, power, electricity, and biofuel [16]. 2.5.2 Wood and Agriculture Products Woody biomass is the accumulated mass, above and below ground, of the roots, wood, bark, and leaves of living and dead woody shrubs and trees [16]. 15 2.5.3 Municipal Solid Waste The portion of MSW could include items such as furniture, pallets, packaging materials processed lumber, and yard and tree trimmings. Some municipalities provide large yard debris carts, which are collected weekly. Other areas work with local businesses to ensure collection options such as drop-off bins and designated collection facilities. [17].These types are shown as the following figure (2.6). Figure (2. 6): Type of biomass [18] 2.6 Advantages of Using Biomass: Using biomass as an alternative source of energy to generate electrical power has some economical benefits. Moreover, it can be a useful source for energy in small societies or small industrial areas. In contrast, even developed countries can use this source to compensate for the lack of the other sources, such as, oil, gas or coal. One of the most important advantages of biomass is 16 its cheap prices; also it is a readily available source of energy. In addition, it is a continuous and long term source, it can be found easily, any time and almost anywhere. One more advantage for biomass power plants is helping to reduce the unemployment in various countries [17, 18]. 2.7 Design of Biogas Plant: A biogas plant consists of three main components as shown in figure (2.7), namely: mixing chamber, digester and expansion chamber. The required quantity of dung and water is mixed in the mixing chamber and this mix in the form of slurry is allowed to flow and be digested inside the digester. The gas produced in the digester is collected in the dome, called gasholder. The digested slurry flows to the expansion tank from the digester through the manhole. The slurry then flows through an overflow opening to the storage pit where it is collected and taken to the fields for application as fertilizer. The gas is supplied to the point of use through a pipeline. Before deciding on the size of plant, it is necessary to collect dung for several days to determine the average daily dung production. The amount of dung available daily helps in determining the size of the plant [19]. 17 Figure (2. 7): Biogas schematic diagram of biogas digester 2.8 Biogas - Digester types The most important types of biogas plants are described as follow: - Fixed-dome plants - Floating-drum plants - Balloon plants - Horizontal plants - Earth-pit plants - Ferrocement plants In developing countries, the selection of appropriate design is determined largely by the prevailing design in the region. Typical design criteria are space, existing structures, cost minimization and substrate availability. The designs of biogas plants in industrialized countries reflect a different set of conditions. In this research we used the ferrocement digester as the reasons listed in Table (2.3). Table (2.3) summarizes the types of digester [4, 19]. 18 Table (2. 3): The types of digesters Digester types Design principle Main components Referred substrates Anticipate d useful life (year) Digester volume (m3) Advantages Disadvantages Floating- drum continuous- feed, mixed digester masonry digester, floating metal gasholder Animal excrements, with or without vegetable waste 8-12 6-100 Easy construction and operation. uniform gas pressure metal gasholder can rust Water-jacket continuous- feed, mixed digester masonry digester, floating metal gasholder in step. water jacket Animal excrements, with or without vegetable waste 10-15 6-100 Very reliable, easy construction and operation. Long useful life, mature Technology. expensive Fixed-dome continuous- feed, mixed digester with slurry store masonry digester, gas holder with displacement pit Animal excrements plus vegetable waste 12-20 6-20 Low cost of construction. long useful life. well insulated Sealing of gasholder. Fluctuating gas pressure. balloon-type continuous- feed, mixed digester with slurry store integrated digester gas-holder made of plastic sheeting Animal excrements only 2-5 4-100 easy operation short useful life plastic mate low gas pressure 19 Earth pit continuous- feed, mixed digester with slurry store earth pit as digester, plastic gasholder Animal excrements 2-5 4-500 extremely inexpensive easy operation Plastic gasholder plus soil permeability Ferrocement continuous- feed, mixed digester with slurry store ferrocement digeste gasholder made of metal or ferrocement Animal excrements, with or without vegetable waste 6-10 4-20 potentially inexpensive, long useful life, easy operation, reliable ferrocement construction not yet adequately time years- tested Horizontal (shallow) continuous- feed, fermentation channel masonry digester, floating metal gas holder or separate Animal excrements, with or without vegetable waste 8-12 20-150 shallowness, easy operation expensive, metal gasholder 20 2.9 Applications of Biogas in Household Digesters 2.9.1 Cooking and Heating Biogas produced from the household digesters is mainly used for cooking. The amount of biogas used for cooking purposes usually varies between 30 to 45 m3 per month [20]. 2.9.2 Biogas Stoves The biogas burners are designed to meet a mixture of bio-gas and air in the ratio of 1:10. The efficiency of the heat entering the vessel from the stove was high for biogas with 57.4%, followed by LPG, kerosene, and wood with 53.6%, 49.5%, and 22.8%, respectively [20]. 2.9.4 Lighting and Power Generation The other major application of household biogas is for lighting and power generation. In many developed countries, biogas from the digesters is sentto a combustion engine to convert it into electrical and mechanical energy [20]. 21 Chapter Three Methodology 22 Chapter Three Methodology The methodology adopted in the research can be divided into five steps, these are: 1) Data collection 2) Biogas production 3) Cost analysis 4) Centralized /decentralized option 5) EIA The steps are shown in figure (3.1) and will be discussed in the following sections. Figure (3. 1): Research Methodology Diagram 23 3.1 Data Collection of Raw Materials Data of animal waste used in this study were collected from the Palestinian Ministry of Agriculture and Palestinian Central Bureau of Statistics. The data include the number of cattle, sheep, goat and poultry in each village in West bank. 3.2 Animal Waste Calculation The amount of organic waste that can be collected for each type of animal is shown in Table (3.1). For the aim of calculation the percent of dry matter, some factors were used as shown in Table (3.14) [21-25]. Animal Animal Weight-kg waste-dung- kg/day Excreta- Fresh DM (%) Range Range Average Poultr y Broilers 1.4-1.3 0.06 0.10- 0.29 0.195 Mothers of Broiler 2 0.15 Layer 2 0.15 Turkey 10 0.45 Cattle Calf (male) 450 30 0.180 Hurry or cow milk (female) 580 34.5 Sheep 60 2 0.18- 0.25 0.215 Goat 40 2 0.18- 0.25 0.215 Total (average) 0.201 Where:DM: Dry Matter Table (3. 1): Amount of animals and poultry waste production http://www.pcbs.gov.ps/ 24 3.3 Biogas Volume Calculation: The amount of biogas was calculated based on the amount of animal’s waste production by using factors listed in Table (3.2) [22, 23]. 3.4 Calculation of energy potential: The energy potential from animal wastes was calculated based on the biogas values and engines efficiency as listed in Table (3.3) [26]. Table (3. 3): parameters for energy calculation Biogas calorific value -MJ/m3 23 Biogas calorific value -kWh/m3 6.4 generator efficiency 0.3 Table (3. 2): Amount and percent of biogas yield from waste of animals and poultry. Animal Biogas yield m3/kg.OTS Range Average Poultry Broilers 0.3-0.8 0.550 Mothers of Broiler Layer Turkey Cattle Calf 0.575 Hurry Cow-milk Sheep 0.3-0.4 0.350 Goat 0.3-0.4 0.350 Total (average) 0.3558 25 3.5 Sizing the Plant The biogas plant size depends on the average daily feed stock and expected hydraulic retention time of the material in the biogas system. Capacity of the plant should be designed based on the availability of raw materials. Sizing of biogas plant is based on three parameters: Daily feed and Retention time [27, 28]. 3.5.1 Sizing the digester The size of the digester is determined based on the retention time and on daily slurry (substrates) supplied as in equation (3.1). Fermentation slurry consists of the feed material and the mixing water. V = Sd ∗ Rt (3 .1) Where: V: Digester volume (m3); where (1m3~ 1000kg) Sd: daily substrate input rate (kg/day) Rt: Retention time (day) 3.6 Cost of Plant The total cost of biogas plant consists from the cost of digester and the cost of generator. The land cost was not included in the total cost, considering the lands are available and awarded from animals farmers owners. 3.6.1 Digester cost The following equation (3.2) was used to calculate the digester cost [29]. DigesterCost (€) = 23182 + (89 ∗ V) (3.2) 26 Where: V: Digester volume (m3) This equation includes Building price (Granular subbase, Bio-reactor, Heat insulation, Gas line, Gas storage, Substrate line) and Techniques price (Heating Pump, Gas preparation, Electrical installation, Tube extruder, Sensors, Controller, and Granary) 3.6.2 Generator Cost: Equation (3.3) was used to calculate the generator cost which includes Engine equipment, Heat line electrical installation, sonic insulated site, then the following equation (3.3) is used [29]. Generator Cost = 11870 + (283 ∗ P) (3.3) Where: P: Rated Engine Power (kW) 3.7 Annual Cost Calculation In order to calculate the cost of kWh produced, then the following steps are followed: [30] 1) Calculate the equivalent annual cost [NIS/year] by using equation (3.4). AW = PW i(1+i)n (1+i)n−1 + O&𝑀 (3.4) Where: AW: is the required equivalent annual worth. PW: the estimated present (now) costs, which includes digester initial cost, generator initial costs, and any other required initial costs [NIS]. 27 O&M: estimated annual operating and maintenance cost [NIS/year], where it could be 5% of the first term from the AW equation shown above. i: annual interest rate [%/year], where values around 10%/year are reasonable. n: project estimated useful life [years], for such project ,16 years is suitable figure . 2) Now, the cost per kWh [NIS/kWh] can be estimated easily by using equation (3.5). kWhcost = AW annual kWhprod (3.5) Where kWh production is the estimated kWh production from the proposed unit size. 3) 0.3NIS/ kWh was taken to be the sales cost for local municipalities in order to compete the Israel Electric Corporation(IEC) where their selling price is about (0.4-0.45). 3.8 Clustering of Power plant Decentralized power plants were formed in centralized cluster, depending on the volume and the distance between the plants. 3.9 Transportation Cost The transporting cost was calculated for the centralized power plant, where the truck transporting the manure was taken to accommodate at least 5 tons, thus any station where less than this weight is not taken into account. We calculated the time for upload and download the manures, where it was 10 minutes calculated for each 5 km. The time of filling the manure in the 28 decentralized power plant and discharging in centralized power plant is considered as one hour. The cost of transport was calculated by the following equations (3.6-8) and this cost included the cost of labor, number of workers per truck, size of the truck and the period which the truck spent in each trip [31]. Cost (NIS/ton) = ((188+0.9*km)/ total wet waste (ton/day)) (3.6) Total cost (NIS/year) = Cost * total wet waste * No. of day (3.7) AWt(NIS/year) = Total cost +AW (3.8) 3.10 Payback Period Calculation The payback period was calculated based on selling cost of kWh to be 0.3 NIS. Levelized cost of energy= AW (NIS) / Energy potential (kWh) (3.9) Profit = Selling cost - Levelized cost of energy (3.10) Yearly profit = Profit *Annual Energy potential (kWh) (3.11) P.B.P=AW (NIS) / Yearly profit (3.12) The average P.B.P was calculated to compare with the centralized power plants. 3.11 Environmental Impact Assessment Taking into consideration the economical, social, political and environmental parameter in centralized and decentralized are discussed in chapter four as Environmental Impact Assessment (EIA) is carried out. 29 Chapter Four Environmental Impact Assessment of Establishing Biogas Plant 30 Chapter Four Environmental Impact Assessment of Establishing Biogas Plant 4.1 Definition of EIA Environmental Impact Assessment, EIA, is a tool for decision-makers to identify potential environmental impacts of proposed projects, to evaluate alternative approaches, and to design and incorporate appropriate prevention, mitigation, management and monitoring measures [32]. EIA process goes though several steps started from screening to the implementation and follow up procedure of the permission of the approval of the project, as illustrated in Figure (4.1). To assess the expected impacts of establishing a biogas production unit on the environment, an environmental, social and economic aspects are carried .EIA should therefore be viewed as an integral part of the project planning process. http://en.wikipedia.org/wiki/Natural_environment 31 Figure (4. 1): Generalized EIA Process Flow-Chart [33] 4.1.1 Project description, and legal and administrative framework: A brief description of any project is necessary before the start of EIA process. This includes: 32 4.1.2 Screening Means the process of determining whether or not an environmental assessment study is required for a proposed development activity based on the laws of Environmental Quality Authority (EQA), for all projects [34]. All information are then required in order to decide if we need to build a centralized biogas plant in each governorate. 4.1.3 Description of the existing environment: Precise data relevant to the site is required: intended uses, quality, physical, biological, social, and economic conditions. This description must include other existing or proposed developments. In addition, quantities analysis of biomass is needed. Ease of transportation of biomass will be taken into consideration for a found decision of centralized and decentralized plant. 4.1.4 Scoping If screening step shows that EIA is needed then the process of establishing the range of action alternatives and potential impacts to be included in terms of reference for environmental assessment studies is called scooping. In our case the physical, biological and Socio-economic impacts of the biogas power plant will be studied. Physical impact :water pollution related to disposal of animal wastes, water pollution from oil type wastes and/or spills used for the maintenance of equipment, noise pollution resulting from the operation of equipments, air 33 pollution resulting from the stack emissions during energy generation, soil problem. Biological impact: included the wildlife and biodiversity. Socio-economic impacts: health/safety, education, culture, population and land use [33]. 4.1.5 Mitigating measures: Means any measure included in the plan for a development activity to avoid, reduce or rectify an adverse environmental impact, or to compensate for an adverse environmental impact by replacing or providing substitute resources [34]. For example the fermentation waste storage areas shall be hermetically covered. This will enable the emission of gaseous compounds to be reduced and the biogas generated in storage to be collected and used. 4.1.6 Environmental management and training and environmental monitoring plan: In order to try and prevent environmental accidents, it is necessary to prepare a document to define the role of each person or group for good environmental management and train workers on issues related to monitoring and training procedures undertaken to enhance the capabilities of the staff and workers [35]. 4.2 Policy and Legal Framework Since its establishment in 1994, the Palestinian Authority (PA) has worked hard to recover and improve the Palestinian environment and strive towards sustainable development. The PA had established the institutions that could 34 deal with the challenges of building a new state and worked hard to build the capacity of the different ministries and agencies along with building the capacity of the human resources. Laws and legislations were also developed and endorsed to organize and manage the various sectors such as environment, water, wastewater, land use planning, etc. Palestinian legislative council PLC is the formal legislative body in Palestine [36]. In 1999 PEAP developed a new environmental law which identifies waste, hazardous materials, and hazardous waste. More information about this law and the summary of the laws and regulations are existing in appendix J [37]. 4.2.1 Environmental Assessment Policy Environmental Assessment policy shall be implemented to support the sustainable economic and social development of the Palestinian people through assisting in the following goals: 1. Ensuring an adequate standard of life in all its aspects, and not negatively affecting the basic needs, and the social, cultural and historical values of people as a result of development activities. 2. Preserving the capacity of the natural environment to clean and sustain it. 3. Conserve biodiversity, landscapes and the sustainable sue of natural resources. 4. Avoiding irreversible environmental damage, and minimizing reversible environmental damage from development activities [36]. 35 4.3 EIA type methods Scoping should be an ongoing exercise throughout the course of the project. The following environmental tools can be used in the scoping exercise [35].  Checklists – Checklists are standard lists of the types of impacts associated with a particular type of project. They comprise list questions on features the project and environments impacts.  Matrices - Matrix methods identify interactions between various project actions and environmental parameters and components.  Networks – these are cause effect flow diagrams used to help in tracing the web relationships that exist between different activities associated with action and environmental system with which they interact  Consultations – with decision-makers, affected communities, environmental interest groups to ensure that all potential impacts are detected. A matrix serves as a checklist and a summary of the impact assessment. The matrices are very suitable for EIAs as they link a particular environmental aspect to a specific action of the development project and in a way explain the nature of the impact. This type of matrix is usually called as interaction matrix. In this project, a leopold matrix will be constructed. Follow are: 1- It can be considered as a basic tool, the matrix provides the assessor with the entire picture of the environmental impacts of the project highlighting the particular part of the project with the major impact. 36 2- It allows the application of only the relevant part of the matrix for a particular project. 3- It indicates both beneficial as well as adverse impacts by writing a plus or minus sign to the entries in the cells. In constructing such matrix, all activities listed these on one axis, and environmental and social conditions are listed on the other axis, and are divided into three major groups:  Physical conditions: soil, water, air…,  Biological conditions: fauna, flora, ecosystems…,  Social and cultural conditions: land use, historical and cultural issues, populations, economy… 4.3.1 Construction of Leopold Matrix for Centralized and Decentralized Biogas Power Plant Potential negative and beneficial impacts are identified for the proposed development prior to, during and after construction activities. The identification and assessment of potential impacts seeks not only to identify the potential impacts, but also to evaluate the significance of the impacts within the framework of the proposed preventative measures and relative to the existing impacts in the area. The impacts relating to the construction and operational phases of the development are described and summarized in the impact matrix below, this was carried out for proposed centralized and decentralized biogas power plants as shown in Table (4.1) and Table (4.2) [38]. 37 Activities Pre construction Construction Operation Environmental Items R o ad a rr an g em en t C o n st ru ct io n a re a p re p ar at io n , g ro u n d w o rk s S it e cl ea ra n ce w at er s o u rc e, S to ra g e w at er t an k A u x il ia ry t u n n el P o w er h o u se W at er i n ta k e M ai n te n an ce s er v ic e/ r ep ai rs O p er at io n o f eq u ip m en t P h y si ca l Microclimate Air - - - - - -- -- - - Water quality - - -- - - - - - Ground waters - - - - -- -- - Noise - - - - - - -- - - - Soil integrity - -- - - - - Soil quality - -- - - - - - B io lo g ic al Birds - - - - - - - - Mammals - - - - Vegetation - - - - - - - - Landscape/visual - -- - - - - S o ci o -e co n o m ic Archaeological sites - Employment ++ ++ ++ ++ ++ ++ ++ ++ Agriculture - - - Living conditions ++ ++ ++ ++ ++ ++ ++ ++ Health - - - - - - - - - - Protected areas  Where: plus (+) or minus (-) sign can be used to show whether an impact is beneficial or adverse. +++ High positive impact - - - High negative impact ++ Medium positive impact - - Medium negative impact + Low positive impact - Low negative impact No impact Table (4. 1): Leopold matrix for centralized biogas power plant 38 Activities Pre construction Construction Operation Environmental Items R o ad a rr an g em en t C o n st ru ct io n a re a p re p ar at io n , g ro u n d w o rk s S it e cl ea ra n ce w at er s o u rc e, S to ra g e w at er t an k A u x il ia ry t u n n el P o w er h o u se W at er i n ta k e M ai n te n an ce s er v ic e/ r ep ai rs O p er at io n o f eq u ip m en t P h y si ca l Microclimate Air -- -- -- -- - --- -- -- -- Water quality -- -- -- -- -- -- -- Ground waters -- -- -- -- -- -- -- Noise -- - -- -- -- - -- -- -- -- Soil integrity -- -- -- -- -- -- Soil quality -- -- -- -- -- -- - B io lo g ic a l Birds -- - -- -- -- -- -- -- Mammals -- - -- -- Vegetation -- - -- - -- -- -- -- Landscape/visual -- -- - - -- -- S o ci o - ec o n o m ic Archaeological sites - Employment + + + + + + + + Agriculture -- -- -- Living conditions + + + + + + + + Health -- -- -- -- -- -- -- -- -- -- Protected areas It is noted that the centralized biogas power plant has less negative environmental impact than decentralized biogas power plant. Section (4.4) illustrates impacts in details. 4.4 Environmental Aspects, Impacts and Mitigation Following the considering of Leopold matrix, then most important impacts on various environmental elements during the construction and operation of the biogas plant are listed in Table (4.3) which summarized the different impact in the construction and operational phases on various environmental elements. Table (4. 2): leopold matrix for decentralized biogas power plant 39 Table (4. 3): the different impact types in the construction and operational phases [36, 39, 40] # Environmental parameter Impact during construction Impact during Operation Mitigation Monitoring Frequency /time Responsible institutions 1 Water quality The potential impacts on surface water quality may arise from increased sediment loads from the stockpiling of construction aggregates and excavation activities during heavy rainfall Increase in water demand. Impact on the water resources - The design and the implementation should comply with the local and international codes. - Water storage reservoir to meet the demand for several days. Document any potential concerns for spills and stagnant water body creation and its resolution - Take photographs prior, during, and post construction to ensure site restoration back to original characteristics as much as practical Twice in year Contractor ,PWA 2 Ground Water Quality and quantity Water pollution (split fuel/oils, wastes - including liquid ones) leaks and potential population and industrial growth Ensure all necessary equipment is available and in good working condition• Ensure that a qualified operator is available at all Maintain a log of all equipment and its condition - Maintain licenses of all operators -Document safe storage of any toxic materials Twice in year Contractor, PWA 40 times of the project activities 3 Air quality -Pollution of air with exhaust gases from construction machinery. - Dust may be emitted during construction and by transport vehicle, but it will have no critical impact in the case of prolonged hot and dry weather the soil shall be watered, if required. - Particulate and gaseous emissions from diesel generating set. Odor from the Anaerobic digester. - Use of properly service machinery during construction. - Continuous regulation of gas production in the digester to ensure constant and effective operation condition. -Regulation of biogas production to ensure minimum flaring and venting of biogas Document baseline noise and air emission during the start and end of the work - Log noise and air emission - Document complaints and how it was resolved Quarterly Contractor, MOA,PWA ,EQA 4 Soil quality and quantity - Soil disturbance due to excavation. - Operating a biogas plant involves the use of grease in -Regular cleaning and proper storage in barrels and its Take photographs prior, during, and post construction to ensure site restoration back Annually Contractor, Municipality ,MOA,PWA 41 - Heavy machinery used will cause soil compaction. - Soil will be removed and re- located to construct foundations and bases. small quantities and maintenance chemicals required for the operation of machines. Impact on the soil is related to emergency cases and Accidents, the probability of which is very low. proper waste disposal. -Limiting the excavation area to original characteristics as much as practical - Document soil placement if moved from original site Review of bid documents to ensure that applicable codes and regulations are incorporated, inspection during construction to ensure that measures are implemented. 5 Noise -Excessive or prolonged exposure to noise (typically more than 8 hrs above 85-90 decibels) leads to hearing loss. -Excess noise at site cause disturbance on the wildlife. - Noise to be controlled by use of acoustic enclosures for respective equipment. -Minimize the unnecessary use of vehicles and equipment Document baseline noise and air emission during the start and end of the work - Log noise and air emission - Document complaints and how it was resolved Weekly Contractor, Municipality, MOL,MENA 6 Health and safety - Fire outbreak increased noise levels from Accidents and injuries to worker - Identification and elimination of potential hazard. Record when the public was informed of work schedules Every time Contractor, MOH,PWA,P WL 42 construction equipment. - The probability of accidents causing a significant impact on the environment is little if building safety and environmental requirements are followed. - Provision and use of appropriate and adequate personal protective equipment ensuring contractor compliance. - Provision adequate firefighting equipment. - Proper training of workers, and use of proper storage tanks and protective clothing. and management plans - Document any concerns and its resolution with work schedules and management plans -Conduct and document with checklists site inspections -Document and report potential health and safety concerns -conduct site visits and document that workers are properly wearing 6 Socio-economic impacts - increasing employment opportunities for the local communities. - Increasing technological and professional know –how among local worker depends on the requirement construction in -assure purchase of high quality material. -improve local economy by involvement of local contractors - putting measure in place to ensure the operational. -procedures are followed always in identification and non conformity Monthl y Contracto r, ,PWA,P WL 43 the construction process at the plan. identified and addressed. 7 Vegetation Disruption or interference of biological resources may occur during construction work activities Change in the landscape, degrade the aesthetic of the project area and cause odors attract insects and rodents attract and create habitat for migratory birds flying over the region during their semi-annual migrations minimize amount of dust generated through construction works activity - Work within the existing road corridors as practical as possible - Install proper fencing or other suiTable protection during project -construction to prevent the exposure of wild and domestic animals to construction hazards Log any presence of wild or domestic animals within the project site and action taken • Take photographs prior, during, and post construction to ensure site restoration back to original characteristics as much as practical Once a year Contractor, Municipality,P WA 8 Employment Opportunities Several categories of employees will be Moreover, the project operation Not required Not required ------ MOL 44 required during the construction phase. This will include skilled and unskilled labors, engineers, and a small number of other professionals. These levels of short-term employment would have a positive impact on the local economy and on regional unemployment. will provide employment for several persons. This would represent a positive long- term significant impact 45 After the result in Table (4.3) it is obvious that centralized biogas power plant is more viable than decentralized biogas plant. Centralized biogas power plant needs less number of used lands, it has less noisy, emission & pollution on nearest residents, more easily for take permission, monitoring, controlling and searching check. 4.5 CO2 Reduction Potential with Biogas Production Average implied carbon emission factors from electricity generation for selected products are presented below. These values represent average CO2 emissions per kWh of electricity produced. 1 kWh produced from biogas stations emits 400g of CO2 to atmosphere. So producing 1kWh will reduce 913g of CO2 [42].  Electrical Energy =104.8 GWh/Year  Reduction of the emission of CO2 = 100,000 ton CO2 per year. In the case of proper utilization of these bioenergy supposed system, it is expected to minimize the amount of green house emissions equivalent to 100,000 ton CO2 which it produced from a same amount of the yearly production electrical energy from coal. 46 Chapter Five Results and Discussion 47 Chapter Five Results and Discussion For the aim of presenting results and discuses of these results data based on Tubas governorate is taken for illustration .Same methodology of interpretation of results for other governorates are presented in appendix (A to I) 5.1 Animals Waste in Palestine Tubas governorate consist of twenty one villages, each village breed many types contains animals such as cattle, goat, sheep, and poultry where the amount of waste of these animals can be used for producing biogas. 'Ein elBeida village has the highest number of cattle of (359), Almailh village has the highest number of goat and sheep of (7,882) and Tammun village has the highest number of poultry of (45,825). As noted, Almalih city has the highest number of animals and Aththaghra city has the lowest number of animals. Considering the number of animals shown in Table (5.1), the amount of animal wastes can be estimated for Tubas Governorate based on Table (3.1). For example, the amount of dry waste of Bardala village as seen in the first village in Table (5.1) can be calculated as below:  The amount of waste (kg/day)=No. of animals * factor of animals waste  For cattle : - Total daily waste =waste of male +waste of female 48 =((15*30) + (180*34.5)) =6660 kg/day - Total annual waste =6660*365*0.9=2,187,810 kg/year (0.9 is a collecting factor)  For sheep : - Total waste =(4788*2)=(9576 kg/day)*0.9*365 = 3,145,716 kg/year  For goat : - Total waste=(942*2)=(1884 kg/day)*0.9*365=618,894 kg/year  For poultry: - Total waste=waste of (broilers+ mother of broilers +layer +turkey)= ((4500*0.06)+(0.0*0.15)+(0.0*0.15)+(6000*0.45) =2970 kg/day - Total annual waste = ((4500*0.06*50)+ (0.0*0.15*365) + (0.0*0.15*365) +(6000*0.45*150)*0.9) =376,650 kg/year Where: the life cycle/year for (broilers=50day, mother of broilers =365 day ,layer =365day,turkey=150day) - Total amount of wet waste for all animals =21090*0.9=18981 kg/day - Total amount of dry waste =total amount of wet waste*avg factor =18981*0.201=3,815kg/day - The amount of animal waste was calculated for all villages in Tubas governorate as in the same pervious method. 49 Table (5. 1): amounts of animal waste in Tubas Governorate [21] Cattle Sheep Goats Poultry Location N o . M a le N o . F em a le W a ste-d u n g -k g /y ea r d ry d u n g -k g /y ea r N o . S h eep W a ste-d u n g -k g /y ea r d ry d u n g -k g /y ea r N o . G o a ts W a ste-d u n g -k g /y ea r d ry d u n g -k g /y ea r N o . W a ste-d u n g -k g /y ea r d ry d u n g -k g /y ea r Bardala 15 180 2,187,810 393,806 4,788 3,145,716 676,329 942 618,894 133,062 10,500 376,650 73,447 'Ein el Beida 68 291 3,968,116 714,261 724 475,668 102,269 264 173,448 37,291 0 0 0 Kardala 15 265 3,151,136 567,205 1,557 1,022,949 219,934 417 273,969 58,903 2,500 6,750 1,316 Ibziq 3 66 777,560 139,961 1,447 950,679 204,396 1,212 796,284 171,201 0 0 0 Salhab 0 0 0 0 743 488,151 104,952 229 150,453 32,347 3,000 147,825 28,826 'Aqqaba 0 17 192,665 34,680 2,194 1,441,458 309,913 235 154,395 33,195 6,900 18,630 3,633 Tayasir 1 8 100,521 18,094 1,479 971,703 208,916 340 223,380 48,027 7,560 256,082 49,936 Al Farisiya 0 1 11,333 2,040 1,906 1,252,242 269,232 180 118,260 25,426 0 0 0 Al 'Aqaba 1 11 134,521 24,214 737 484,209 104,105 632 415,224 89,273 1,800 4,860 948 AthThaghra 0 1 11,333 2,040 223 146,511 31,500 67 44,019 9,464 800 2,160 421 Al Malih 30 493 5,882,942 1,058,930 5,308 3,487,356 749,782 2,574 1,691,118 363,590 0 0 0 Tubas 45 206 2,778,125 500,062 3,522 2,313,954 497,500 1,227 806,139 173,320 21,650 221,468 43,186 Kashda 0 1 11,333 2,040 374 245,718 52,829 62 40,734 8,758 0 0 0 50 Khirbet Yarza 16 147 1,823,668 328,260 711 467,127 100,432 707 464,499 99,867 0 0 0 Ras al Far'a 0 30 339,998 61,200 1,501 986,157 212,024 63 41,391 8,899 12,000 591,300 115,304 El Far'aCamp 13 12 264,114 47,541 166 109,062 23,448 43 28,251 6,074 0 0 0 Khirbet arRas al Ahmar 0 0 0 0 5,679 3,731,103 802,187 347 227,979 49,015 0 0 0 Wadi al Far'a 11 43 595,735 107,232 1,489 978,273 210,329 381 250,317 53,818 9,900 133,853 26,101 Tammun 5 36 457,272 82,309 4,828 3,171,996 681,979 670 440,190 94,641 45,825 492,986 96,132 Khirbet 'Atuf 5 24 321,273 57,829 3,859 2,535,363 545,103 1,033 678,681 145,916 9,000 24,300 4,739 Khirbet Humsa 0 0 0 0 2,748 1,805,436 388,169 861 565,677 121,621 0 0 0 Total 228 1,832 23,009,454 4,141,702 45,983 30,210,831 6,495,329 12,486 8,203,302 1,763,710 131,435 2,276,863 443,988 51 The total number of animals and amount of waste for all governorates is given in Table (5.2).We notice that Hebron governorate has the highest number of animals and Salfeet governorate has the lowest number of animal Table (5. 2): annual amounts of animal waste for all Governorates Governorate No. of Animals Dry waste (kg/day) Tubas 191,964 33,820 Hebron 1,181,018 128,360 Bethlehem 270135 25,817 Jericho 284,097 30,495 Ramallah 554,523 33,197 Nablus 831,701 66,530 Qalqilya 694,276 30,654 Salfeet 74,150 8,745 Tulkarem 631,277 27,625 Jenin 1,161,012 77,638 5.2 Potential of Biogas Production The main advantage of animal manure, with respect to continuous digesters, is that it is easy to collect and easy to mix as slurry and load into digesters. The biogas produced from the digestion of each waste type is different from the others. The total biogas was calculated by taking only the dry animals waste. Tables (5.3) summarize the amount of biogas than can be produced from different animal waste at Tubas Governorate. The amount of biogas was calculated based on the Table (3.2). For example the amount of biogas production of Bardala village can be calculated as the below method.  The volume of biogas per day =total amount of dry animal waste*factor of biogas 52 =3815 *0.3558 =1,357 m3/day The potential of biogas was calculated for all villages in Tubas governorate as the same pervious methods and is given in Table (5.3). Table (5. 3): The Potential of Biogas Production for Tubas Governorates Villages Total dry waste for all animals kg/day Total Biogas (m3/day) Bardala 3815 1,357 'Ein el Beida 2339 815 Kardala 2347 797 Ibziq 1412 445 Salhab 463 148 Aqqaba 1115 348 Tayasir 930 301 Al Farisiya 812 244 Al 'Aqaba 617 191 AthThaghra 127 40 Al Malih 5951 1,953 Tubas 3522 1,169 Kashda 174 52 Khirbet Yarza 1448 486 Ras al Far'a 1124 385 El Far'a Camp 211 71 Khirbet arRas al Ahmar 2332 699 Wadi al Far'a 1174 386 Tammun 3354 1,127 Khirbet 'Atuf 2157 667 Khirbet Humsa 1397 419 Total 36887 12,033 The potential of biogas production for Tubas governorate was found to be about 12,033 m3/day. Almalih village has the highest amount of biogas but 53 Aththaghra village has the lowest amount of biogas, Table (5.4) shows the potential of biogas production for all Governorates. Table (5. 4): The Potential of Biogas Production for all Governorates governorate Total Biogas (m3/day) Tubas 12,033 Hebron 45,670 Bethlehem 9,186 Jericho 10,850 Ramallah 11,811 Nablus 23,671 Qalqilya 10,907 Salfeet 2,860 Tulkarem 9,829 Jenin 27,623 Total 144,460 Hebron governorate has the highest potential of biogas where Salfeet governorate has the lowest potential of biogas. 5.3 Electrical Energy Production Based on data presented in Tables (5.1) and (5.2), the total amount of electrical energy that can be produced for biogas is calculated with reference to parameters presented in Table (3.3). The electrical energy potentials are summarized in Tables (5.5). For example the annual electrical energy production of Bardala village can be calculated as the below method.  Daily electrical energy production = biogas yield*calorific value *generator efficiency = (6.4*1357*0.3) 54 = 2605 kWh/day Taking attainment value of 90%, then the daily energy production will be calculated as:  Annual electrical energy production = daily electrical energy * working days = (2605*365*0.9) =855,887 kWh/year The potential of electrical energy production for Tubas governorate is about 8.48GWh Table (5. 5): The annual electrical energy potential production in Tubas Governorate Village Total E (kWh)/year Bardala 855,887 'Ein el Beida 693202 Kardala 644464 Ibziq 328568 Salhab 97865 'Aqqaba 222553 Tayasir 195706 Al Farisiya 164834 Al 'Aqaba 128623 AthThaghra 24749 Al Malih 1529382 Tubas 835279 Kashda 35843 Khirbet Yarza 393938 Ras al Far'a 262559 El Far'a Camp 57336 Khirbet arRas al Ahmar 471087 Wadi al Far'a 258474 Tammun 573756 Khirbet 'Atuf 435903 Khirbet Humsa 282136 55 Table (5.6) shows the potential of electrical energy production for all Governorates with 104.8 GWh total energy. Table (5.6): Potential of annual electrical energy production for all Governorates Governorate Total E (kWh)/year Tubas 8,479,570 Hebron 28,805,225 Bethlehem 5,793,541 Jericho 6,843,332 Ramallah 7,449,674 Nablus 14,929,970 Qalqilya 6,878,982 Salfeet 2,001,104 Tulkarem 6,199,421 Jenin 17,422,693 Total 104.8 GWh 5.4 Sizing the Digester The digester volume was calculated for each village of Tubas governorate using equation (3.1). For example the digester volume of Bardala village can be calculated as:  Digester volume =daily dry waste *ratio of mixing water *retention time = 3815 *2.25*40=343 m3, where (1m3~ 1000kg) The digester volume of biogas plant for all villages in Tubas governorate was calculated as the same pervious method and is given in Table (5.7) [27,28]. 56 Table (5. 7): calculated sizes of digesters for Tubas Governorate Village volume (m3) Bardala 343 'Ein el Beida 206 Kardala 202 Ibziq 113 Salhab 38 'Aqqaba 88 Tayasir 76 Al Farisiya 62 Al 'Aqaba 48 AthThaghra 10 Al Malih 494 Tubas 296 Kashda 13 Khirbet Yarza 123 Ras al Far'a 97 El Far'a Camp 18 Khirbet arRas al Ahmar 177 Wadi al Far'a 98 Tammun 285 Khirbet 'Atuf 169 Khirbet Humsa 106 If all waste collected for Tubas villages will be treated in one digester, then the total digester volume of biogas plant in Tubas governorate will be about 3,044m3 . Same calculations are carried out to all governorates, and the results are given in Table (5.8). 57 Table (5. 8): Electricity sizes of digester for all Governorates Governorate volume (m3) Tubas 3,061 Hebron 11,552 Bethlehem 2,324 Jericho 2,745 Ramallah 2,988 Nablus 5,987 Qalqilya 2,759 Salfeet 787 Tulkarem 2,486 Jenin 6,987 5.5 Analysis Cost of Biogas Plant The cost of biogas power plant for each village in Tubas governorate is calculated using equations (3.2) and (3.3). The cost of Bardala village plant is calculated as:  Total cost of biogas power plant =digester cost + generator cost - Digester cost (€) =23182 +(89*digester volume) =23182 + (89*343) =53,709€ - Generator cost (€)=11870 +(283*Power) = 11870+ (283*97) =39,321€ Total of biogas power plant=52161+38099 =930, 30€ equivalent to 390,726 NIS The total cost of biogas plant for all villages in Tubas governorate was calculated using the above method and the results are given in Table (5.9). 58 Table (5. 9): Total cost of proposed biogas power plant for Tubas Governorate Village v o lu m e (m 3) P o w er (k w ) co st o f p lan t(€ ) co st o f g en erato r (€ ) to tal co st (€ ) to tal co st (N IS ) Bardala 343 97 53,709 39,321 930,30 390,726 'Ein el Beida 206 58.7 41,535 28,481 70,016 294,065 Kardala 202 57.4 41,131 28,115 69,246 290,834 Ibziq 113 32.1 33,217 20,952 54,169 227,509 Salhab 38 10.7 26,526 14,897 41,423 173,978 'Aqqaba 88 25.1 31,033 18,975 50,008 210,034 Tayasir 76 21.7 29,960 18,005 47,965 201,451 Al Farisiya 62 17.6 28,675 16,841 45,516 191,166 Al 'Aqaba 48 13.8 27,485 15,765 43,250 181,650 AthThaghra 10 2.8 24,070 12,674 36,744 154,326 Al Malih 494 140.6 67,149 51,664 118,814 499,017 Tubas 296 84.2 49,517 35,706 85,223 357,937 Kashda 13 3.8 24,366 12,941 37,307 156,689 Khirbet Yarza 123 35.0 34,134 21,782 55,916 234,848 Ras al Far'a 97 27.7 31,842 19,708 51,550 216,509 El Far'a Camp 18 5.1 24,778 13,314 38,092 159,985 Khirbet arRas al Ahmar 177 50.3 38,919 26,113 65,032 273,133 Wadi al Far'a 98 27.8 31,868 19,732 51,600 216,719 Tammun 285 81.1 48,546 34,827 83,372 350,164 Khirbet 'Atuf 169 48.0 38,201 25,464 63,665 267,395 Khirbet Humsa 106 30.1 32,607 20,400 53,007 222,630 The total cost of Tubas biogas plants is about 2,326,398 NIS and the cost of plant for all governorates is shown in Table (5.10) 59 Table (5. 10): Total cost of biogas power plant for all Governorates Governorate Total cost (NIS) Tubas 2,327,235 Hebron 8,373,931 Bethlehem 1,801,842 Jericho 2,101,660 Ramallah 2,274,830 Nablus 4,411,187 Qalqilya 2,111,841 Salfeet 679,002 Tulkarem 1,917,760 Jenin 5,123,103 Total 31,122,391 5.6 Equivalent Annual Cost Calculation The annual cost [NIS/year] for each village of Tubas governorate is calculated by equations (3.4). Thereby for Bardala village the equivalent annual cost is determined by: - PW of Bardala village =390,729 NIS - i:interest rate =10% /year - operating and maintenance cost =5% of PW/year - n: life time =16 year - then, AW=69,478 NIS/year AW = PW i(1 + i)n (1 + i)n − 1 + O&𝑀 The estimated present cost (PW) which includes the cost of digester and cost of generator as we calculated in the previous section (5.5). 60 The annual worth of biogas plant for all villages in Tubas governorate was calculated using the pervious method and the results are given in Table (5.11) Table (5. 6): The equivalent annual cost for proposed biogas plants for Tubas Governorate Governorate AW( NIS/year) Bardala 69478 'Ein el Beida 56896 Kardala 55767 Ibziq 42554 Salhab 31314 'Aqqaba 38222 Tayasir 36467 Al Farisiya 35017 Al 'Aqaba 32973 AthThaghra 27535 Al Malih 98679 Tubas 67403 Kashda 28085 Khirbet Yarza 44345 Ras al Far'a 39236 El Far'a Camp 28824 Khirbet arRas al Ahmar 51494 Wadi al Far'a 39435 Tammun 60082 Khirbet 'Atuf 49597 Khirbet Humsa 41340 The equivalent annual cost of all Governorates is shown in Table (5.12). 61 Table (5. 7): The equivalent annual cost for proposed biogas plants for all Governorates Governorate AW( NIS) Hebron 1,489,024 Bethlehem 320,397 Jericho 373,710 Ramallah 404,503 Nablus 784,382 Qalqilya 375,520 Salfeet 126774 Tulkarem 3410010 Jenin 910973  The cost per kWh [NIS/kWh] is determined by equation (3.5), Where: kWhcost = AW annual kWhprod - AW for Bardala village =69478 NIS/year - Annual kWh production as the pervious section (5.3) is 843303 kWh - kWh Cost =0.0812NIS/kWh The kWh Cost of biogas plant for all villages in Tubas governorate was calculated and the results are given in Table (5.13). 62 Table (5. 8): The cost of one kWh for proposed biogas plants for Tubas governorate Village AW( NIS) cost(NIS)/kWh Bardala 69478 0.0812 'Ein el Beida 56896 0.0820 Kardala 55767 0.0865 Ibziq 42554 0.1295 Salhab 31314 0.3199 'Aqqaba 38222 0.1717 Tayasir 36467 0.1863 Al Farisiya 35017 0.2124 Al 'Aqaba 32973 0.2563 AthThaghra 27535 1.1125 Al Malih 98679 0.0645 Tubas 67403 0.0806 Kashda 28085 0.7835 Khirbet Yarza 44345 0.1125 Ras al Far'a 39236 0.1494 El Far'a Camp 28824 0.5027 Khirbet arRas alAhmar 51494 0.1093 Wadi al Far'a 39435 0.1525 Tammun 60082 0.1047 Khirbet 'Atuf 49597 0.1137 Khirbet Humsa 41340 0.1465 - It is noted from figure (5.1), the curve starts sloping when the volume of digester is about 100m3; which is considered as critical point for determining the feasible volume for construct decentralized biogas power plant, also if the volume of digester less than 100m3, the production cost of kWh being more than selling cost. Therefore, it is obvious that the volume of digester needed for decentralized biogas power plant should be greater than 100 m3. 63 Figure (5. 1):The relationship between volume and cost of produced electrical energy (NIS/kWh) 5.7 Decentralized and Centralized Power Plant 5.7.1 Proposed Decentralized Biogas Plant for Tubas Governorate A distributed energy system is a relatively new approach in the power industry in most countries. Traditionally, the power industry has focused on developing large, central power stations and transmitting generation loads across long transmission and distribution lines to consumers in the region. Decentralized energy systems seek to put power sources closer to the end user. A decentralized system, are suitable in rural areas where the population density is low. Often much more economically feasible than centralized power plant. [41] For the purpose of centralizing villages to use one digester, then all villages with digester volume less than 100m3 are discarded and all villages that need to use a digester of greater than 100m3 as grouped. This is illustrated in Figure (5.2). 0.00000 0.20000 0.40000 0.60000 0.80000 1.00000 1.20000 0 100 200 300 400 500 600 C o st ( N IS /K W h ) volume m3 64 Figure (5. 2):proposed decentralized biogas Plant for Tubas Governorate 5.7.1.1 Payback Period Calculation (S.P.B.P) The P.B.P is determined by equations (3.9-12).For example the P.B.P of Bardala village can be calculated as the below method. - Profit =selling cost – levelized cost of energy - Profit = 0.3-0.0812 =0.2188 NIS/kWh 65 - Yearly profit =profit *Electrical Energy =0.2188 * 855,887 =187,268 NIS/year - P.B.P = AW / Yearly profit =69,478 /187,268=0.37 - 0.3NIS/ kWh was taken to be the sales cost for local municipalities in order to compete the Israel Electric Corporation(IEC) where their selling price is about (0.4-0.45). The P.B.P was calculated of biogas plant for all villages in Tubas governorate as the same pervious method as shown in Table (5.14) Table (5. 9): P.B.P of Proposed Decentralized biogas power plant for Tubas Governorate Village P.B.P (year) Bardala 0.37 'Ein el Beida 0.5 Kardala 0.5 Ibziq 0.9 Salhab N.F* 'Aqqaba 1.3 Tayasir 1.7 Al Farisiya 2.8 Al 'Aqaba 8.4 AthThaghra N.F* Al Malih 0.3 Tubas 0.4 Kashda N.F* Khirbet Yarza 0.8 Ras al Far'a 1.1 El Far'a Camp N.F* Khirbet arRas al Ahmar 0.6 Wadi al Far'a 1.1 Tammun 0.4 Khirbet 'Atuf 0.6 Khirbet Humsa 1.0 ** NF*: not feasible 66 From Table (5.14), it is noticed that construction a biogas digester at El Far'a Camp, Al 'Aqaba, Kashda and Aththaghra, Salhab are not feasible because the size of digester is less than100 m3, therefore producing cost of one kWh is higher than selling price. 5.7.2 Proposed Centralized Biogas Plant for Tubas Governorate Tubas governorate was divided into groups of villages, where the central village is the most manures’ producer. Villages were distributed to the groups according to the nearest villages from the central village. Tubas Governorate was divided into three clusters the main cities in these cluster are: Almalha, Bardala and Tubas in figure (5.3). 67 Figure (5. 3): The main proposed clusters in Tubas Governorate 68 - The first cluster (group 1) as shown in Table (5.15) consists of (Badala, Einalbaida, Kardala and Alfaresia) villages, the main city in this cluster is Bardala which has the highest amount of animal waste and volume of digester in biogas power plant. - The second cluster (group 2) as shown in Table (5.16) consists of (Almalih, Kherbit Yzara, Kherbit alras, Atuf and Humsa) villages, the main city in this cluster is Almalih which has the highest amount of animal waste and volume of digester in biogas power plant. - The third cluster (group 3) as shown in Table (5.17) consists of (Ibziq,Tayasir ,Aqaba,Rasalfara,Wadi alfaraa ,Tammun and Tubas) villages , the main city in this cluster is Tubas which has the highest amount of animal waste and volume of digester . In this section the distance to the main city, total cost of transportation, AW and P.B.P was calculated using the following methods. As illustrated below for first cluster:  Cost of transportation =( 188+0.9*total distance) /total amount of waste - Cost of transportation =(188+(0.9*(12*2)/25.9=8.1 NIS/ton Where the total animals waste calculated without animals waste of Bardala village.  Total cost of transportation = cost of transportation *total wet waste *No. of working days. 69 - Total cost of transportation =8.1*25.9*365*0.9=68,854 NIS/Year  AW with transportation cost of centralized biogas power plant =total cost of transportation+ total AW of all villages - AW with transportation cost=68,854+126,873 =195,726 NIS  P.B.P=0.5 year as shown previously 70 Table (5. 10): calculation for first cluster (group 1) in proposed centralized biogas power plant for Tubas Governorate Village NO. of Animals wet waste kg/day Biogas (m3) Electricity (kWh) Vd (m3) Power (kw) Total cost of decen. plant (NIS) AW of decen. Plant (NIS) distance to (bardala km) Total Cost of Cent. plant (NIS) AW of Cent. plant (NIS) Total Cost of trans. (NIS) AW including Trans. costs(NIS) P.B.P Bardala 16,425 18,891 1,357 855,887 343 97 390,729 69,478 - 713,505 126,873 68,854 195,726 0.5 Einalbai d 1,347 11,385 815 514,174 206 59 294,065 52,290 4 Kardala 4,754 11,134 797 502,861 202 57 290,834 51,715 1.5 Alfaresi a 2,087 3,407 244 153,881 62 18 191,166 33,993 6.5 Total 24,613 41,410 2,969 1,782,922 751 213 71 Table (5. 1611): calculation for second cluster (group 2) in proposed centralized biogas power plant for Tubas Governorate Village NO. of Animals Wet waste kg/day Biogas (m3) Electricity (kWh) Vd (m3) Power (kw) Total cost of plant (NIS) AW (NIS) distance to (Almalih) km Total Cost of Cent. plant (NIS) AW of Cent. plant (NIS) Total Cost of trans. (NIS) AW including Trans. costs(NIS) P.B.P Al Malih 8,405 27,275 1,953 1,231,796 494 141 499,017 88,733 - 908,149 161,484 80,324 239,828 0.435 Khirbet Yarza 1,581 6,794 486 306,829 123 35 234,848 41,760 4.5 Khirbet ar Ras 6,026 9,762 699 440,882 177 50 273,133 48,568 7 Khirbet atuf 13,921 9,317 667 420,789 169 48 267,395 47,547 10 Khirbet humsa 3,609 5,847 419 264,046 106 30 222,630 39,587 11 Total 33,542 58,995 4,224 2,664,343 1,069 304 72 Table (5. 12): calculation for third cluster (group 3) in proposed centralized biogas power plant for Tubas Governorate Village NO. of Animals wet waste kg/day Biogas (m3) Electricity (kWh) Vd (m3) Power (kw) Total cost of plant (NIS) AW (NIS) distance to (Tubas) km Total Cost of Cent. plant (NIS) AW of Cent. plant (NIS) Total Cost of trans. (NIS AW including Transporta tion costs(NIS) P.B.P Ibziq 2,728 6,225 446 281,130 113 32 227,509 40,455 8 897,012 159,504 80,979 242,281 0.44 Tayasir 9,346 4,870 349 219,944 88 25 210,034 37,348 4.5 Al 'Aqaba 9,388 4,205 301 189,892 76 22 201,451 35,821 3.5 Ras al Far'a 13,594 5,372 385 242,615 97 28 216,509 38,499 4.5 Wadi al Far'a 11,824 5,388 386 243,351 98 28 216,719 38,536 6.5 Tammun 51,364 15,734 1127 710,600 285 81 350,164 62,265 4.5 Tubas 26,650 16,337 1170 737,815 296 84 357,937 63,647 - Total 124,894 58,131 4,162 2,625,347 1,053 300 73 5.7.2.2 Summary of Proposed Centralized Biogas Power Plant for Tubas Governorate We note that the cluster of Almalih has the largest amount of biogas production. Consequently, it has the largest volume of digester. Also, it has the largest total cost of other plants. On the other hand, P.