domestic biogas in asia1

Domestic Biogas in Asia

Dr David Fulford CEnv MEIwww.kingdombio.com

davidf@kingdombio.com

What is biogas?

•Anaerobic Digestion (AD) breaks down wet biomass to gas and compost

•Relies on microbes (bacteria and archaea) in animal dung

•Several possible applications

•Talk focuses on biogas in rural areas for domestic uses, with dung as feed

Background• SNV (Netherlands Development Organisation)

Asia Biogas programme - focus on rural domestic biogas fed by animal dung.

• Started in Nepal (1993) - extended to Vietnam, Bangladesh, Cambodia and Laos

•Based on previous programme set up Development and Consulting Services of United Mission to Nepal (1976 to 1984)

Technology

• Dung mixed with water and allowed to flow into underground pit lined with masonry

• Plants built for individual households• Need 3 to 6 cows or 6 to 12 pigs• Gas piped to kitchen for cooking

•Slurry from plant collected

•Can be used as a fertilizer after some processing

•Removes smell

Benefits (1)• Clean gaseous cooking fuel• No smoke• Instant availability • Does not need constant attention• Reduced danger of burns

•Resource (dung) available from animal sheds

•No need to walk to collect firewood

Benefits (2)• Cooking pots easy to clean (no soot)• Saving of time (3 hours a day)• Saving of firewood (2,000 kg a year)• Reduced deforestation (1,000 biogas plants

saves 33.8 ha forest from clear felling)

•Much reduced smell from the animal sheds

(in Vietnam, pig sties are close to the house)

Benefits (3)• Biogas can be used for lights• Reduced smell from kerosene lamps• Savings of 32 litres kerosene a year• Reduced risk of house fires• Saving of carbon (4,900 kg a year)

•Since gas available in the morning, children get cooked breakfast before school.

Benefits (4)• A latrine can be attached• Improved sanitation• Reduced transfer of pathogens (especially if

slurry is properly processed)

•Reduced risk to women (who go out at dawn or dusk to use the fields)

•Reduce incidence of snake bites

Benefits (5)• Slurry is a good quality compost (better than

raw dung)• Liquid slurry should be absorbed in dry

biomass and composted for 1 month

•Compost even better if use vermi-culture

•Growers prepared to pay cash for vermi-compost

Economics• With so many benefits, what is drawback?• Cost - most cost:benefit analyses show

financial benefit as marginal• BUT high value for “externalities” - e.g.

saving forests, health benefits etc.

•Biogas becomes attractive with subsidy

•SNV Asia Biogas Programme offered reliable subsidy

Asia Biogas Programme • Involve people at all levels, from government

policy makers to masons who build plants• Promotion, Education and Training• Emphasis on quality of technology• Use a local design, but ensure it works well

•Train staff to check quality of construction

•Release subsidy for each plant only when it meets specification

HouseholdBiogas Sector

Quality Management

Marketing & Sales

Construction

Subsidy

Extra services

R&D

Training

Micro Credit, SME

Development

Tasks involved in running a biogas programme

Ref: Dagmar Zwebe, “SNV Renewable Energy Developments: The Biogas Programme for Animal Husbandry Sector of Vietnam”, Presentation (May 2012).

Project Achievements

CountryStartYear

Built in 2011

Built by 2011

Invest Cost $

Nepal 1992 19,246 250,476 663

Vietnam 2003 23,372 123,714 621

Cambodia 2006 4,826 20,756 488

Bangladesh 2006 5,049 14,972 430

Laos 2007 439 2,405 448

Total 52,932 412,323

Based on: Brief progress and planning report the Working Group on Domestic Biogas under the Energy for All Partnership as per May 2012

Starting a Programme

• Find a group interested in biogas to manage programme (or set up a group)

• Involve people from government and encourage renewable energy policy

• Design a subsidy & micro-finance scheme

•Develop a local design that works well

•Use local companies to build plants

•Train staff regularly

Subsidy Issues (1)

• Who funds externalities? i.e.• Who pays to save forests, improve people’s

health, reduce carbon emissions? • National governments - but other priorities• International Community

•Bilateral Aid (SNV, KfW, DANIDA, USAID etc)

•UN agencies:World Bank, ADB, UNDP,

UNEP, UNFCCC•Danger of corruption

Subsidy Issues (2)

• WWF puts high value on certain habitats: e.g. tiger ranges - pay extra

• CDM designed to fund carbon offsets - CER certified emissions reductions

• Also VER - voluntary emissions reductions

•Carbon offset trading under voluntary market mechanisms

(Big companies want to look “Green”)

•Complex - large nos. needed

Carbon Offset Biogas

• New Charitable Company established• Foundation SKG Sangha - based on biogas

programme in South India• Aim: to use voluntary carbon offset finance to

encourage biogas projects elsewhere

•Also interest in other renewable energy projects

•First project in Egypt funded by UNDP

Thank you

Technical Aspects • Underground dome made from masonry

(bricks or concrete)• Gas stored by displacing slurry into

reservoir tank• Volume 4 m3 (2 m3 to 10 m3)

Biogas Displacement Principle

Thank you

Other applications (1)• Sewage Treatment • KIST project in Rwanda processing sewage

from prisons (10,000 people)• Saves 50% of wood fuel for cooking• Volume 100 m3 x 10 = 1,000 m3

Other applications (2)• Urban biogas to process food wastes• Volume 1 m3, food waste gives more gas• Family’s own food waste saves 25% LPG• Use extra food waste from local shops• Can use sewage in addition

Other applications (3)• Local authority wastes• Market wastes• Office canteen wastes• Municipal solid wastes• Food processing wastes

Thank you