Bioenergy for communal energy supply

Ir. Bart Frederiks (FACT Foundation)Landelijke dag Burkina Faso Platform, 6 November 2010

http://burkinafasoplatform.nl

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Contents1. About FACT Foundation2. Overview of bioenergy3. Vegetable oil and biodiesel4. Biogas5. Gasification6. RE techniques compared7. Some final notes

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1. About FACT Foundation (1)• Mission: FACT promotes sustainable biofuels for local

communities in developing countries, by providing knowledge and expertise on biofuel implementation, by field testing innovative biofuels and by giving specialist advice on demand.

• Organisation:– Established 2005 by Kees Daey Ouwens– Board and advisory board– Staff: Director; Experts (2); Controller; Administrative support– Students and volunteers– Large international network of experts, NGO’s, universities, private

sector operators

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1. About FACT Foundation (2)• Activities:

– Knowledge Centre: collection, generation, verification and dissemination of knowledge, from own R&D, own projects and other’s projects. Reports, website, documentaries etc.

– Innovation Programme: field-testing innovative bioenergy concepts relevant for community application.

– Advisory services: consultancy. Technical assistance, studies, training, etc.

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2. Overview Bioenergy (1)• Definition

– Bioenergy is energy produced from materials of biological origin (excluding material embedded in geological formations and transformed to fossil)

• Main conversion processes– Thermochemical conversion processes (combustion, gasification,

carbonisation, pyrolysis)– Biological conversion processes (anaerobic digestion, fermentation)– In addition one can distinguish physical processes (distillation,

extraction, densification) and chemical processes (transesterification) • Examples

– Wood burning for heating or cooking– Charcoal production and use– Manure digestion for biogas– Ethanol production from sugar cane molasses– Rice husk gasification for electricity production

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2. Overview Bioenergy (2)• Advantages

– Use of (low-value) residues or purposely grown biomass– Biomass and biofuels can be stored– Opportunities for local farmers– Limited investment costs– Renewable and GHG neutral (short carbon cycle)

• Disadvantages– Requires skill and dedication to operate and maintain– Less suitable for smaller scale electricity production (<1 kW)– Complicated logistics at large scale– Competitiveness with other RE techniques

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3. Vegetable oil and biodiesel (1)• Vegetable oil (PPO or SVO) can be used as a diesel substitute in

engines (or stoves, lamps)• The oil needs to be clean, and certain properties (particles,

acidity, phosphorous) need to be within limits• Because of the higher viscosity of PPO, engines need to be

modified so that they heat up the oil before it is injected• See also Jatropha Handbook

Jatropha oil Palm oil Cotton seed oil Diesel

Density (g/cm³) 0.92 0.93 0.92 0.83Viscosity (mm²/s) 52 37-40* 50 2.7Cetane Number 40-45 42-62 42-48 47Acid value (mg KOH/g) 0.92 6.9 0.07 -

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3. Vegetable oil and biodiesel (2)• Advantages of PPO

– Clean, high-value fuel that can be stored for long periods– Can be produced locally, money stays in local economy– Relatively uncomplex technology– Limited investment costs

• Disadvantages of PPO– Relatively high production costs, not much cheaper than diesel– Competition with land / labour (agricultural calendar)– Use as engine fuel requires engine modification

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3. Vegetable oil and biodiesel (3)• Jatropha Curcas L. (JCL) is a drought resistant shrub that

produces seeds with a high oil content (40%)– Myth: JCL thrives on infertile seeds, and produces high amounts of seeds

with no inputs (water, labour, nutrients)– Reality: JCL can indeed withstand extended periods of drought, but it does

need water and nutrients – otherwise it does not produce seeds!

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3. Vegetable oil and biodiesel (4)• The economics of JCL are disputable

– Typical seed yields in rainfed situations are up to 500-1000 kg/ha; higher yields can be achieved with irrigation and fertilizers

– Typical seeds prices are in the order of 0.08-0.10 EUR/kg– At low input, the returns can be up to 100 EUR/ha (1000 kg) which

requires considerable labour (weeding, harvesting); other crops yield a multiple!

– At high input, the returns can be several hundreds EUR/ha but this does not outweigh the additional inputs (irrigation, fertilizers)

– JCL in hedges can be an option; yields are low but inputs are limited to labour for harvesting

• Bottom line: be very careful when considering Jatropha, and beware of overestimated expectations!

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3. Vegetable oil and biodiesel (5)• Example: Rural electrification with JCL oil in Garalo, Mali

– 300 kW power plant supplying >300 clients– 3 modified diesel engines– JCL seed production is falling behind the expected rates, many fields

abandoned– See also video section on www.fact-foundation.com

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3. Vegetable oil and biodiesel (6)• Biodiesel is a liquid fuel made from vegetable oil with properties

close to normal (fossil) diesel, and can be used in conventional diesel engines without modifications

• Biodiesel is produced by transesterification, a chemical process; main inputs are vegetable oil and methanol (or ethanol)

Mali Biocarburant’s Biodiesel plant(Koulikoro, Mali)

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3. Vegetable oil and biodiesel (7)• Advantages of biodiesel

– Refined fuel, can be used in any diesel engine– Different types of oil can be used for production– High value product

• Disadvantages of biodiesel– Chemical process, requires certain scale and skill– Some inputs (methanol) may be difficult to obtain– Production costs

• New developments– Production with (anhydrous) ethanol instead of Methanol; experiments

with hydrous ethanol are ongoing– MBSA is exploring biodiesel production in Burkina Faso

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4. Biogas (1)• Biogas is a flammable gas (~60% methane, 40% CO₂) that is

produced during anaerobic decomposition of biomass• Typical process features

– Inputs: biomass (animal manure, other organic matter), water– Outputs: biogas (typical yield 200-400 l/kg DM), effluent (fertilizer)– Typical retention time: 50 days– Ambient temperature (32-34°C is optimum)

• Applications– Household scale (4-10 m³ digesters) - well proven around the world– Electricity production – well proven on large scale (NL, DE etc), few

examples of rural electrification– Recent initiative: fuel for Multifunctional Platform, replacing part of the

diesel fuel consumption

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4. Biogas (2)• Advantages of biogas

– Relatively uncomplex, easy to operate– Limited investment and production costs– Effluent retains fertiliser value

• Disadvantages of biogas– Water requirements– Low solids content of effluent– Large volume / space requirements

• New developments– Low cost digester designs– Co-substrates (eg water hyacinth, Euphorbia Tirucali, JCL / shea residues)– Water recirculation

4000 m³ digester being started up(W-Sumatra, Indonesia)

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4. Biogas (3)• Example

– Rural electrification system for 300-400 households, 8 h/d service– 500 m³ digester, 50 kW gas engine– Daily inputs: 1.8 t manure, 0.8 t organic material, 3.4 m³ water– Daily production: 160 kWh, 5.5 t wet effluent– Production costs: approx 0.25-0.30 EUR/kWh

Impression of a village scale biogas electrification system

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5. Gasification (1)• Biomass gasification is a thermo-chemical conversion process in

which biomass reacts with a limited amount of air (or another oxydising agent), resulting in a combustible gas

• The gas (called producer gas) can be used for the production of power (in a gas or diesel engine)

• Suitable fuels: wood, corn cobbs, rice husk, …

200 kW rice husk gasifier for ruralelectrification (Bat Doeng, Cambodia)

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5. Gasification (2)• Advantages of gasification

– Low fuel costs: wood or residues– Relatively high energy efficiency– Competitive with alternatives (eg diesel)

• Disadvantages of gasification– Relatively sensitive process; skill level required– Relatively high investment costs– Disposal of effluents (scrubbing water)

• New developments– Recently a gasification system was implemented in Burkina Faso (Po)

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5. Gasification (3)• Example: village electrification system

– 50 kWe gasifier (Indian) supplying electricity to an isolated grid– Fuels: fast growing wood (Leucaena), 1.5 kg/kWh wood – Operation and maintenance by 2 full time staff– Production costs: approx 0.25-0.30 EUR/kWh, mainly capital costs

Community energy cooperative, gasifier and Leucaena (Anlung Tamey, Cambodia)

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6. Electrification techniques compared50 kWe system Diesel PPO Biogas GasificationInvestment costs (‘000 EUR) 15-20 20-30 40-50 60-80Production costs (EUR/kWh) 0.36 0.33 0.27 0.27

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Diesel PPO Biogas Gas ifi cation

System type

Prod

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osts

(EU

R/kW

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Financia l costs

Depreciation

Operational costs

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7. Some final notes• Start with determining the actual energy demand in a

community. Electricity? Cooking fuel? Only for consumptive uses or also for productive uses?

• Bioenergy is not always the best option – consider all the local resources (including other renewables but also grid connection)

• Concerning bioenergy, look into available residues (eg manure, rice husk, corn cobbs) before considering growing biomass

• Consider the locally available technical and organisational capacities

• Look for smart combinations with productive uses

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• Thank you for your attention! • Any questions?

http://burkinafasoplatform.nl