Technical Works

After a thorough study, scrutinising various regionally used biodigester models, a fixed dome design, the ‘Farmer’s Friend Biodigester’ has been selected as the most appropriate model for mass dissemination in Cambodia by the National Biodigester Programme. This design is based on the ‘Deenbandhu’ model which is in use in great numbers for more than 20 years in India.

The biodigester reduces green house gas (GHG) emissions through 3 pathways: 1) substitution of non-renewable cooking and lighting fuel by a renewable fuel (biogas), 2) reduce methane emissions from livestock manure by capturing and burning methane for thermal energy (cooking and lighting) and 3) displacement of chemical fertilizers by bio-slurry.

The design selection criteria included:
  • urability, reliability and maintenance requirements;
  • local availability of construction materials;
  • appropriateness of the design for areas with high water tables;
  • costs.

The design is presently available in 5 different sizes: 4, 6, 8, 10 and 15 m3. The table below gives the daily required input, gas production and fuelwood equivalent per plant volume.

Biodigester size Initial feeding Daily dung feeding (kg) Use of Biogas Stove (hour) Use of Biogas Lamp (hour) Fuelwood replacement value (kg)1
4 1500 20 to 40 2 to 4 8 -16 4-8
6 2300 40 to 60 4 to 6 16 -24 8-12
8 3000 60 to 80 6 to 8 24-32 12-16
10 3800 80 to 100 8 to 10 32-40 16-20
15 6000 100 to 150 10 to 15 40-60 28-32

1 Based on a commonly used, low tech, woodstove with a 10% efficiency rate. 1 m3 biogas will replace about 5kg of fuelwood.

Support from the programme

Plant owner will receive proper services both technical and final aspect from NBP as follow:
  • Subsidy 150$
  • Low interest loan from NBP partnered MFIs
  • Quality control during construction and end construction
  • Two year warranty on dome structure and one year on appliances (except biogas lamp)
  • Biodigester is steady and used more than 20 years
  • Free of charge on user training on operation, maintenance and bio slurry management
Biodigester Provides

FREE gas for Cooking......

Cooking on biogas is easy and efficient. A biogas stove is analogous to the gas stoves found in many western homes. Biogas stoves are safe for indoor use and a switch to biogas will eliminate the dangers of indoor air pollution – a threat to the lives and livelihoods of women and children in many (sub)tropical regions. The alleviation of health risks associated with indoor air pollution may directly result in a reduction in healthcare costs and as well as an increase in productive days. Moreover, cooking on biogas is fast. Biogas eliminates the process of preheating, which is a necessary step when cooking on biomass.

FREE gas for Lightenning......

Biogas may be used for lighting. Biogas lamps allow households that are off of the energy grid to light their homes after dark, enabling children to study and family members to engage in new forms of business, such as craft-making. Biogas lamps are brighter than their kerosene counterparts and safer for domestic use. Unlike a kerosene lamp, a biogas lamp cannot be knocked over, thereby mitigating fire danger in the home.

FREE best natural fertilizer for all type of crops, mixing animal food……

applied directly to crops to increase agricultural productivity. The use of biogas-slurry not only saves money otherwise spent on chemical fertilisers, but reduces the negative effects of such fertilisers on the environment. It is estimated that the application of biogas-slurry may increase productivity as much as 25% when compared to applying manure directly to fields.