Nongwa Ag, Thailand — Thai farmer Boon Lua, his wife, and two sons cook three meals a day on pig power.
The power comes from methane gas, extracted from the animal waste of some 700 pigs raised on the Boon family farm near Bangkok.
Manufacture of biogas, as the waste byproduct is known, requires a special chamber to digest manure until it degrades and produces methane. Pipes carry the gas to a stove where it is burned. The biogas is cheaper for the Boon family than kerosene or even firewood.
Mr. Boon, a prosperous farmer, was able to afford a biogas plant. Such devices are touted by village development experts as a solution to high energy costs and rapid deforestation from wood gathering.
For most of Asia's peasants, however, the initial cost of buying a device to recycle animal waste into energy are still too high.
''The technology is available,'' said Dr. J. Gururaja, a United Nations energy expert in Bangkok. ''But the capital and social barriers are too high.''
In rural India, where some 250 million head of cattle roam the land, small digesters of two- to three-cubic-meter capacity have been used to produce methane from cow dung. But their use has been limited because they are barely competitive with kerosene for cooking.
''Villagers ask, 'Why should I pay $300 for a biogas plant when that is two to three times my income?' '' says Dr. Gururja.
Also, villagers must often collect animal dung from fields to be placed in a biogas container -- a labor-intensive chore.
''There's a lot of talk of biogas in India, but not much has been done,'' says Dr. Gururaja.
''Only China has been able to promote biogas plants with some success,'' he says. Large manure digesters of 8 to 10 cubic meters have a relatively low capital cost of about $70 and are now fully competitive with kerosene. An estimated 7 million biogas contraptions of one sort or another are producing energy in China.
An experiment with very large digester of 2,500 cubic meters is under way in Papua New Guinea, which proposes to use biogas for industrial power.
In extremely poor countries such as India, biogas plants could worsen poverty for the poorest peasants, says Mohandas K. Samuels, an economist with the Asian Development Bank. Cow chips now picked up by the absolutely poor for cooking fuel would be denied them if the cows' owners suddenly started using the chips for a biogas plant.
Still, Asia could have 20 million biogas plants by the year 2000, according to Prof. Pradeep Rohatgi of the Indian Council of Scientific and Industrial Research. The doubling in agricultural waste expected by then should be an incentive to more people to buy these plants.