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− | | + | [[Portal:Biogas|► Back to Biogas Portal]] |
− | [[Portal:Biogas|-> Back to Biogas Portal]] | + | |
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| = Overview = | | = Overview = |
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| Failure or unsatisfactory performance of biogas units occur mostly due to planning mistakes. The consequences of such mistakes may be immediately evident or may only become apparent after several years. Thorough and careful planning is, therefore, of utmost importance to eliminate mistakes before they reach irreversible stages. | | Failure or unsatisfactory performance of biogas units occur mostly due to planning mistakes. The consequences of such mistakes may be immediately evident or may only become apparent after several years. Thorough and careful planning is, therefore, of utmost importance to eliminate mistakes before they reach irreversible stages. |
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− | As a biogas unit is an expensive investment, it should not be erected as a temporary set-up. Therefore, determining [[Siting of the Biogas Unit|siting criteria for the stable and the biogas plant]] are the important initial steps of planning. | + | As a biogas unit is an expensive investment, it should not be erected as a temporary set-up. Therefore, determining [[Siting_of_the_Biogas_Unit|siting criteria for the stable and the biogas plant]] are the important initial steps of planning. |
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| A general problem for the planning engineer is the interference of the customer during planning. As much as the wishes and expectations of customers have to be taken into consideration, the most important task of the planner is to lay the foundation for a well functioning biogas unit. As in most cases the customer has no experience with biogas technology, the planner has to explain all the reasons for each planning step. Planners should have the courage to withdraw from the planning process, if the wishes of the customer will lead to a white elephant on the farm. | | A general problem for the planning engineer is the interference of the customer during planning. As much as the wishes and expectations of customers have to be taken into consideration, the most important task of the planner is to lay the foundation for a well functioning biogas unit. As in most cases the customer has no experience with biogas technology, the planner has to explain all the reasons for each planning step. Planners should have the courage to withdraw from the planning process, if the wishes of the customer will lead to a white elephant on the farm. |
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− | Moreover, all extension-service advice concerning agricultural biogas plants must begin with an estimation of the quantitative and qualitative energy requirements of the interested party. Then, the biogas-generating potential must be calculated on the basis of the given [[Balancing Biogas Production and Energy Demand|biomass production]] and compared to the [[Balancing Biogas Production and Energy Demand#Determining the Energy Demand|energy demand]]. Both the energy demand and the gas-generating potential, however, are variables that cannot be accurately determined in the planning phase. [[Sizing of the Biogas Plant|Sizing the plant]](digester, gasholder, etc.) is the next step in the planning process. | + | Moreover, all extension-service advice concerning agricultural biogas plants must begin with an estimation of the quantitative and qualitative energy requirements of the interested party. Then, the biogas-generating potential must be calculated on the basis of the given [[Balancing_Biogas_Production_and_Energy_Demand|biomass production]] and compared to the [[Balancing_Biogas_Production_and_Energy_Demand#Determining_the_Energy_Demand|energy demand]]. Both the energy demand and the gas-generating potential, however, are variables that cannot be accurately determined in the planning phase. [[Sizing_of_the_Biogas_Plant|Sizing the plant]](digester, gasholder, etc.) is the next step in the planning process. |
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| In the case of a family-size biogas plant intended primarily as a source of energy, implementation should only be recommended, if the plant can be expected to cover the calculated energy demand. | | In the case of a family-size biogas plant intended primarily as a source of energy, implementation should only be recommended, if the plant can be expected to cover the calculated energy demand. |
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− | Information about the economic evaluation of a biogas plant can be found in the section on [[Biogas - Costs and Benefits|Costs and Benefits]]. | + | Information about the economic evaluation of a biogas plant can be found in the section on [[Biogas_-_Costs_and_Benefits|Costs and Benefits]]. |
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| <br/> | | <br/> |
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− | Before building a biogas plant, there are different circumstances which should be considered. For instance, the natural and agricultural conditions in the specific countries are as important as the [[Biogas Framework#Social Aspects in the Planning Process|social or the economic aspects]]. To consider the most important factors, we provide a [[Checklist for the Planning of a Biogas Plant|checklist for the planning procedure]], a '''planning guide''' and a [[Checklist for the Construction of a Biogas Plant|checklist for construction]] of a biogas plant. | + | Before building a biogas plant, there are different circumstances which should be considered. For instance, the natural and agricultural conditions in the specific countries are as important as the [[Biogas_Framework#Social_Aspects_in_the_Planning_Process|social or the economic aspects]]. To consider the most important factors, we provide a [[Checklist_for_the_Planning_of_a_Biogas_Plant|checklist for the planning procedure]], a '''planning guide''' and a [[Checklist_for_the_Construction_of_a_Biogas_Plant|checklist for construction]] of a biogas plant. |
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| <br/> | | <br/> |
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| If only one of the following criteria is evident, then the widespread dissemination of simple household biogas plants is not possible. As an exception, suitable farms in the region could allow individual measures that make biogas a feasible technology. | | If only one of the following criteria is evident, then the widespread dissemination of simple household biogas plants is not possible. As an exception, suitable farms in the region could allow individual measures that make biogas a feasible technology. |
| + | |
| *too cold or too dry region | | *too cold or too dry region |
| *very irregular or no gas demand | | *very irregular or no gas demand |
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| Each of the following factors will lead to severe problems in biogas dissemination. Accompanying measures, particularly modified technical developments, high financial promotion or additional organizational structures within the dissemination program are necessary to guarantee project success. | | Each of the following factors will lead to severe problems in biogas dissemination. Accompanying measures, particularly modified technical developments, high financial promotion or additional organizational structures within the dissemination program are necessary to guarantee project success. |
| + | |
| *low income or unstable economic situation of the target group | | *low income or unstable economic situation of the target group |
| *unfavorable macro- and micro-economic conditions | | *unfavorable macro- and micro-economic conditions |
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| If each of the following conditions is fulfilled then household biogas plants will definitely be a success. A dissemination program is then strongly recommended. | | If each of the following conditions is fulfilled then household biogas plants will definitely be a success. A dissemination program is then strongly recommended. |
| + | |
| *even, daily temperatures over 20ºC throughout the year | | *even, daily temperatures over 20ºC throughout the year |
| *regular gas demand approximately corresponding to gas production | | *regular gas demand approximately corresponding to gas production |
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| <u>Evaluation criteria are:</u><br/> | | <u>Evaluation criteria are:</u><br/> |
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| *Siting condition are favorable<br/> | | *Siting condition are favorable<br/> |
| *Siting condition are unfavorable, but | | *Siting condition are unfavorable, but |
| **a) compensable by project activities | | **a) compensable by project activities |
| **b) not serious enough to cause ultimate failure | | **b) not serious enough to cause ultimate failure |
| + | |
| *Siting condition are not satisfactory | | *Siting condition are not satisfactory |
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| <br/>Despite its detailed nature, this planning guide is only a framework within which the extension officer should proceed to conduct a careful investigation and give due consideration, however subjectively, to the individual conditions in order to arrive at a locally practical solution. By no means is this planning guide intended to relieve the agricultural extension officer of the responsibility to thoroughly familiarize himself with the on-the-spot situation and to judge the overall value of a given location on the basis of the knowledge thus gained.<br/> | | <br/>Despite its detailed nature, this planning guide is only a framework within which the extension officer should proceed to conduct a careful investigation and give due consideration, however subjectively, to the individual conditions in order to arrive at a locally practical solution. By no means is this planning guide intended to relieve the agricultural extension officer of the responsibility to thoroughly familiarize himself with the on-the-spot situation and to judge the overall value of a given location on the basis of the knowledge thus gained.<br/> |
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| == Initial Situation == | | == Initial Situation == |
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| | style="vertical-align: bottom" | '''- o +''' | | | style="vertical-align: bottom" | '''- o +''' |
| |} | | |} |
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| <br/> | | <br/> |
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| | style="width: 465px" | '''Prior energy supply''' | | | style="width: 465px" | '''Prior energy supply''' |
| Uses, source of energy, consumption:<br/> | | Uses, source of energy, consumption:<br/> |
| + | |
| *'''Anticipated biogas demand (kwh/day or l/d)'''<br/> | | *'''Anticipated biogas demand (kwh/day or l/d)'''<br/> |
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| <br/> | | <br/> |
− | *
| + | |
− | ****:for cooking:
| + | *:for cooking: |
| + | |
| *:for lighting:<br/> | | *:for lighting:<br/> |
| *:for cooling:<br/> | | *:for cooling:<br/> |
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| *:b) desired demand coverage:<br/> | | *:b) desired demand coverage:<br/> |
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− | <br/>'''Available biomass (kg/d) and potential gas production (l/d) '''<span style="font-weight: bold; line-height: 1.5em">from animal husbandry</span> | + | <br/>'''Available biomass (kg/d) and potential gas production (l/d) '''<span style="font-weight: bold; line-height: 1.5em">from animal husbandry</span> |
− | *
| + | |
− | ****:pigs:
| + | *:pigs: |
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| *:poultry: | | *:poultry: |
| *:cattle: | | *:cattle: |
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| The following steps serve as a step by step guideline to reach a decision whether a biogas project is technically and economically feasible. | | The following steps serve as a step by step guideline to reach a decision whether a biogas project is technically and economically feasible. |
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− | '''Basic steps in planning a biogas plant according to '''[http://giz.energypedia.info/Enterprises Krieg & Fischer]''':''' | + | '''Basic steps in planning a biogas plant according to ''''''Krieg & Fischer:''' |
| + | |
| #Calculation of biogas amount | | #Calculation of biogas amount |
| #Size of digester | | #Size of digester |
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| '''Basic Steps according to the "Guide to Biogas" from FNR:''' | | '''Basic Steps according to the "Guide to Biogas" from FNR:''' |
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| + | <br/> |
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| === Step 1: Preparing the project outline === | | === Step 1: Preparing the project outline === |
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− | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" | + | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" |
| |- | | |- |
| | bgcolor="#ccffcc" style="width: 228px" | Long-term availability of substrates | | | bgcolor="#ccffcc" style="width: 228px" | Long-term availability of substrates |
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| '''Goals''' | | '''Goals''' |
| + | |
| *'''Initial assessment of the possibilities''' | | *'''Initial assessment of the possibilities''' |
− | *'''Gathering of experience from other [http://giz.energypedia.info/GIZ programms related to Biogas biogas plants]''' | + | *'''Gathering of experience from other biogas plants.''' |
− | *'''Acquisition of knowledge about what [http://giz.energypedia.info/Construction of a biogas plant plants/components are] available on the market'''<br/> | + | *'''Acquisition of knowledge about what [[Parts_of_a_Biogas_Plant|plants/components are]] available on the market''' |
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| <br/> | | <br/> |
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| === Step 2: Developing the feasibility study === | | === Step 2: Developing the feasibility study === |
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− | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" | + | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" |
| |- | | |- |
− | | bgcolor="#ccffcc" style="width: 228px" | Availability of [https://energypedia.info/index.php/Substrate_Types_and_Management substrates] | + | | bgcolor="#ccffcc" style="width: 228px" | Availability of [[Substrate_Types_and_Management|substrates]] |
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− | Check whether it makes sense to have a feasibility study carried out by using the | + | Check whether it makes sense to have a feasibility study |
− | | + | |
− | [http://giz.energypedia.info/Pre-feasibility study template pre-feasibility study template]
| + | |
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| Engage the services of an experienced and reputable engineering firm/engineering department of an experienced<br/>and reputable plant manufacturer. | | Engage the services of an experienced and reputable engineering firm/engineering department of an experienced<br/>and reputable plant manufacturer. |
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| |- | | |- |
− | | bgcolor="#ccffcc" style="width: 228px" | Get in touch with an [http://giz.energypedia.info/Who is who in Biogas agricultural adviser] / professional consultancy | + | | bgcolor="#ccffcc" style="width: 228px" | Get in touch with an agricultural adviser / professional consultancy |
| | An agricultural adviser or biogas consultant experienced in the building and operation of biogas plants should be approached for site selection and plant design through, construction and commissioning. | | | An agricultural adviser or biogas consultant experienced in the building and operation of biogas plants should be approached for site selection and plant design through, construction and commissioning. |
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| <br/>'''Question of procedure:''' | | <br/>'''Question of procedure:''' |
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− | How should the project be implemented? Is a turn-key plant possible?<br/>What does the plant [http://giz.energypedia.info/Construction of a biogas plant construction process] look like?<br/>How high is the available workforce? | + | How should the project be implemented? Is a turn-key plant possible?<br/>What does the plant construction process look like?<br/>How high is the available workforce? |
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| Can the project be multiplicated to other sites?<br/>Which contract works are planned to put out to tender? (e.g. earthworks, electrics…) | | Can the project be multiplicated to other sites?<br/>Which contract works are planned to put out to tender? (e.g. earthworks, electrics…) |
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| '''Goals''' | | '''Goals''' |
| + | |
| *'''Involvement of an experienced engineering firm or adviser for preparation of a feasibility study.''' | | *'''Involvement of an experienced engineering firm or adviser for preparation of a feasibility study.''' |
| *'''Determination of the preferred size of plant and type of plant/procedure with possible feedin points for power, heat or processed biogas''' | | *'''Determination of the preferred size of plant and type of plant/procedure with possible feedin points for power, heat or processed biogas''' |
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− | Engineering firms and companies that we have experience with take a look at the [http://giz.energypedia.info/Service Pack Biogas Who is Who in Biogas.]
| + | <br/> |
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| <br/> | | <br/> |
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| === Step 3: Availability of substrate === | | === Step 3: Availability of substrate === |
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− | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" | + | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" |
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| | bgcolor="#ccffcc" style="width: 200px" | Available substrates | | | bgcolor="#ccffcc" style="width: 200px" | Available substrates |
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| | style="width: 537px" | Which biomass substrates are available: | | | style="width: 537px" | Which biomass substrates are available: |
− | *agricultural residues (e.g. [https://energypedia.info/index.php/Substrate_Types_and_Management#Cattle_dung_and_manure cattle manure], poultry excrement) | + | *agricultural residues (e.g. [[Substrate_Types_and_Management#Cattle_Dung|cattle manure]], poultry excrement) |
| *agroindustrial wastes (e.g. apple mash, POME) | | *agroindustrial wastes (e.g. apple mash, POME) |
| *wastes from trade and industry (e.g. grease trap waste) | | *wastes from trade and industry (e.g. grease trap waste) |
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| '''Goals''' | | '''Goals''' |
| + | |
| *'''Selection of substrates with a view to a workable digestion process.''' | | *'''Selection of substrates with a view to a workable digestion process.''' |
| *'''Definition of measures for pretreatment and processing of substrates.''' '''Selection of potential biomass suppliers.''' | | *'''Definition of measures for pretreatment and processing of substrates.''' '''Selection of potential biomass suppliers.''' |
| + | |
| + | <br/> |
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| <br/> | | <br/> |
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| It must first of all be clarified whether the preferred site is of the necessary size, whether the subsoil is suitable and, if possible, free from contamination, whether any existing buildings and storage areas are in a usable condition and whether grid connection points and heat offtakers are available. The purpose of such an assessment is to keep down the construction costs. The relatively low capacitiesinvolved in agricultural biogas production and the associated substrate streams allow the supply of substrate and the disposal of digestate to be effected by road transport. Many substrates scarcely merit the cost of transport on account of their relatively low energy density. Consequently, the search for substrates with which to supply the biogas plant will focus on biomass that is available from the immediate regional vicinity. It will be advantageous to select a site that has access to roads of average transport capacity (such as country roads/B-roads.) | | It must first of all be clarified whether the preferred site is of the necessary size, whether the subsoil is suitable and, if possible, free from contamination, whether any existing buildings and storage areas are in a usable condition and whether grid connection points and heat offtakers are available. The purpose of such an assessment is to keep down the construction costs. The relatively low capacitiesinvolved in agricultural biogas production and the associated substrate streams allow the supply of substrate and the disposal of digestate to be effected by road transport. Many substrates scarcely merit the cost of transport on account of their relatively low energy density. Consequently, the search for substrates with which to supply the biogas plant will focus on biomass that is available from the immediate regional vicinity. It will be advantageous to select a site that has access to roads of average transport capacity (such as country roads/B-roads.) |
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− | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" | + | {| cellspacing="1" cellpadding="1" border="1" align="center" style="font-size: 14px; width: 777px" |
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| | bgcolor="#ccffcc" style="width: 228px" | The site | | | bgcolor="#ccffcc" style="width: 228px" | The site |
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| '''Goals''' | | '''Goals''' |
| + | |
| *'''Selection of the site''' | | *'''Selection of the site''' |
| *'''Selection of form of biogas utilisation (CHP unit at the site, setting-up of a satellite CHP unit or processing of biogas for feed-in to the natural gas grid)''' | | *'''Selection of form of biogas utilisation (CHP unit at the site, setting-up of a satellite CHP unit or processing of biogas for feed-in to the natural gas grid)''' |
| *'''Building-up of local acceptance through campaign and Human Capacity Development''' | | *'''Building-up of local acceptance through campaign and Human Capacity Development''' |
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− | <br/>Find another detailed site evaluation procedure in [https://energypedia.info/index.php/Siting_of_the_Biogas_Unit energypedia.] | + | <br/>Find another detailed site evaluation procedure in [[Siting_of_the_Biogas_Unit|energypedia.]] |
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| <br/> | | <br/> |
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| === Step 5: Material stream logistics === | | === Step 5: Material stream logistics === |
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| | bgcolor="#ccffcc" style="width: 228px" | Material stream volumes | | | bgcolor="#ccffcc" style="width: 228px" | Material stream volumes |
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| '''Goals''' | | '''Goals''' |
| + | |
| *'''Determination of transport and handling technologies''' | | *'''Determination of transport and handling technologies''' |
| *'''Definition of available area for substrate and digestate storage at the site of the biogas plant''' | | *'''Definition of available area for substrate and digestate storage at the site of the biogas plant''' |
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| === Step 6: Selecting the technology === | | === Step 6: Selecting the technology === |
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| | bgcolor="#ccffcc" style="width: 228px" | Selection of digestion process | | | bgcolor="#ccffcc" style="width: 228px" | Selection of digestion process |
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| '''Goals''' | | '''Goals''' |
| + | |
| *'''Selection of state-of-the-art plant components of high-grade, maintenance-friendly materials with automated operation.''' | | *'''Selection of state-of-the-art plant components of high-grade, maintenance-friendly materials with automated operation.''' |
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| === Step 7: Recovering the energy from the biogas === | | === Step 7: Recovering the energy from the biogas === |
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| | bgcolor="#ccffcc" style="width: 228px" | Type of biogas utilisation | | | bgcolor="#ccffcc" style="width: 228px" | Type of biogas utilisation |
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| '''Goals''' | | '''Goals''' |
| + | |
| *'''Selection of method of energy recovery from biogas''' | | *'''Selection of method of energy recovery from biogas''' |
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| === Step 8: Evaluation and decision-making === | | === Step 8: Evaluation and decision-making === |
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| | bgcolor="#ccffcc" style="width: 228px" | Detailed cost budget | | | bgcolor="#ccffcc" style="width: 228px" | Detailed cost budget |
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| The cost items should be broken down into the following blocks: | | The cost items should be broken down into the following blocks: |
| + | |
| *costs of individual components | | *costs of individual components |
| *substrate costs (delivery 'free to digester') | | *substrate costs (delivery 'free to digester') |
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| <br/>'''Goals''' | | <br/>'''Goals''' |
| + | |
| *'''Preparation of a profitability analysis, taking account of the assessment of other advantages''' | | *'''Preparation of a profitability analysis, taking account of the assessment of other advantages''' |
| *'''Profitability analysis as a decision-making basis''' | | *'''Profitability analysis as a decision-making basis''' |
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| = Further Information = | | = Further Information = |
| | | |
− | * | + | *[[:Category:Biogas|See all Biogas Articles on energypedia]] |
− | | + | |
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| + | <br/> |
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| = References = | | = References = |
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| [[Category:Biogas]] | | [[Category:Biogas]] |
| + | [[Category:Tools]] |
Failure or unsatisfactory performance of biogas units occur mostly due to planning mistakes. The consequences of such mistakes may be immediately evident or may only become apparent after several years. Thorough and careful planning is, therefore, of utmost importance to eliminate mistakes before they reach irreversible stages.
As a biogas unit is an expensive investment, it should not be erected as a temporary set-up. Therefore, determining siting criteria for the stable and the biogas plant are the important initial steps of planning.
A general problem for the planning engineer is the interference of the customer during planning. As much as the wishes and expectations of customers have to be taken into consideration, the most important task of the planner is to lay the foundation for a well functioning biogas unit. As in most cases the customer has no experience with biogas technology, the planner has to explain all the reasons for each planning step. Planners should have the courage to withdraw from the planning process, if the wishes of the customer will lead to a white elephant on the farm.
Moreover, all extension-service advice concerning agricultural biogas plants must begin with an estimation of the quantitative and qualitative energy requirements of the interested party. Then, the biogas-generating potential must be calculated on the basis of the given biomass production and compared to the energy demand. Both the energy demand and the gas-generating potential, however, are variables that cannot be accurately determined in the planning phase. Sizing the plant(digester, gasholder, etc.) is the next step in the planning process.
In the case of a family-size biogas plant intended primarily as a source of energy, implementation should only be recommended, if the plant can be expected to cover the calculated energy demand.
Information about the economic evaluation of a biogas plant can be found in the section on Costs and Benefits.
Before building a biogas plant, there are different circumstances which should be considered. For instance, the natural and agricultural conditions in the specific countries are as important as the social or the economic aspects. To consider the most important factors, we provide a checklist for the planning procedure, a planning guide and a checklist for construction of a biogas plant.
Throughout the world, a countless number of designs of biogas plants have been developed under specific climatic and socio-economic conditions. Chosing a design is essentially part of the planning process. It is, however, important to familiarize with basic design considerations before the actual planning process begins. This refers to the planning of a single biogas unit as well as to the planning of biogas-programs with a regional scope.
The performance of a biogas plant is dependent on the local conditions in terms of climate, soil conditions, the substrate for digestion and building material availability. The design must respond to these conditions. In areas with generally low temperatures, insulation and heating devices may be important. If bedrock occurs frequently, the design must avoid deep excavation work. The amount and type of substrate to be digested have a bearing on size and design of the digester and the inlet and outlet construction. The choice of design will also be based on the building materials which are available reliably and at reasonable cost.
If only one of the following criteria is evident, then the widespread dissemination of simple household biogas plants is not possible. As an exception, suitable farms in the region could allow individual measures that make biogas a feasible technology.
Each of the following factors will lead to severe problems in biogas dissemination. Accompanying measures, particularly modified technical developments, high financial promotion or additional organizational structures within the dissemination program are necessary to guarantee project success.
If each of the following conditions is fulfilled then household biogas plants will definitely be a success. A dissemination program is then strongly recommended.
For larger biogas programs, especially when aiming at a self-supporting dissemination process, standards in dimensions, quality and pricing are essential. Standard procedures, standard drawings and forms and standardized contracts between the constructor, the planner, the provider of material and the customer avoid mistakes and misunderstandings and save time. There is, however a trade-off between the benefits of standardization and the necessity of individual, appropriate solutions.
The design selection is determined largely be the prevailing design in the region, which, in turn takes the climatic, economic and substrate specific conditions into consideration. Large plants are designed on a case-to-case basis.
This guide to planning is intended to serve agricultural extension officers as a comprehensive tool for arriving at decisions concerning the suitability of locations for family-sized biogas plants. The detailed planning outline has a data column for entering the gathered information and a rating column for noting the results of evaluation.
The following steps serve as a step by step guideline to reach a decision whether a biogas project is technically and economically feasible.
It must first of all be clarified whether the preferred site is of the necessary size, whether the subsoil is suitable and, if possible, free from contamination, whether any existing buildings and storage areas are in a usable condition and whether grid connection points and heat offtakers are available. The purpose of such an assessment is to keep down the construction costs. The relatively low capacitiesinvolved in agricultural biogas production and the associated substrate streams allow the supply of substrate and the disposal of digestate to be effected by road transport. Many substrates scarcely merit the cost of transport on account of their relatively low energy density. Consequently, the search for substrates with which to supply the biogas plant will focus on biomass that is available from the immediate regional vicinity. It will be advantageous to select a site that has access to roads of average transport capacity (such as country roads/B-roads.)