Manila — When Conzalo Catan Jr. talks about how ''green charcoal'' can stop destruction of Asia's forests, you would think he invented plastic.
''This stuff can help those rural people who must walk miles for firewood,'' the Filipino entrepreneur says. ''And they don't have to cut down the few precious forests we have left. We are losing trees at a dangerous rate. A substitute has to be found.''
Mr. Catan's invention of ''green charcoal'' -- a black chunk of compacted grass made from rice waste and other crops -- is just one of many ways being offered to reduce the amount of wood being burned by rural peasants.
In a number of Asian countries, especially China, Nepal, Thailand, and the Philippines, forests are being denuded at an alarming rate, caused mainly by poor squatters and farmers seeking new land in the ''slash and burn'' style of agriculture. Since the primary fuel for a majority of Asian is firewood, deforestation has become a ''second energy crisis'' after oil.
The World Bank estimates that three-quarters of the people in developing countries use traditional fuels, mostly wood, for cooking, and that these fuels supply one-quarter of the total energy use. In Asia, traditional fuel use varies from 70 percent in Nepal, Burma, and Afghanistan to 7 percent in Korea (urbanized Hong Kong and Singapore show negligible use).
In the last few years government programs to replant trees have generally failed to halt deforestation. ''Wood plantations are stripped before they grow up,'' says Mohandas K. Samuels, an Asian Development Bank energy expert.
Instead, several efforts are now being made to make wood substitutes and to promote cooking stoves that burn less wood for the same amount of heat.
''Firewood,'' says Dr. Samuels, ''can no longer be considered a renewable resource. The increasing exploitation has outstripped the natural regeneration of supplies.''
In March, green charcoal received the backing of a $200,000 Philippine government loan to build a 25-ton-a-day production plant near Manila. At present , Mr. Catan's Greenergy Corporation makes 3.5 tons a day of the fuel, mainly for heating and cooking in a bakery, restaurant, and poultry farm.
The poultry farm, says Mr. Catan, pays an average 5 cents for green charcoal to heat one egg until it hatches a chick. That compares with 12 cents for electricity, 8 cents for natural gas, and 5 cents for wood charcoal, he says.
Mr. Catan, who has other patents to his name and owns a leading Filipino pest-control firm called Mapecon, invented green charcoal about five years ago. He threw some bacteria on a pile of dry rice hulls left over from a harvest. The microbes fermented the grass slightly and made it burn more easily. He compressed the fermented waste into pellets the size of small tree branches and -- voila -- Mr. Catan had a patentable process.
Besides a new plant here, he has licensed the process to a Mexican company and hopes to export green charcoal logs to the United States as a substitute for wood and chemical logs. In the Philippines, Mr. Catan plans to sell his product to households for about 36 cents a pound. (One pound produces 7,000 to 10,000 B.t.u.s of heat.)
With abundant rice waste and other agricultural refuse, Asia's countryside could conceivably support such a wood-substitute idea. But the economics of Mr. Catan's venture have not been fully tested. He figures the 25-ton-a-day plant will need about 100 workers. Some 25 to 30 families would be paid about 5 cents a ton to collect 50 to 70 tons of raw material a day, which could include rice hulls, corn cobs, peanut shells, or coconut husks.
If there is a flaw in the idea, it will be the high cost of collection, says Dr. Samuels. To solve the potential problem, Mr. Catan is working on an invention -- a mobile unit to go through rice fields and pelletize waste on site.
But Mr. Catan has competition, chiefly from inventors of more efficient stoves.
There are plenty of new designs available in developing countries, but the problem lies in getting villagers to accept and pay for them. ''If stoves used now were twice as efficient in burning, the trend towards deforestation can be arrested,'' says Dr. J. Gururaja, a United Nations energy specialist.
India and Sri Lanka among Asian nations are using incentives to actively promote new stoves. In Sri Lanka, the cooking units go for about $1 each, and wood briquettes are sold commercially. Substitution of aluminum cooking pots and pans for earthen ones in India has raised the efficiency of traditional fuels in rural areas.
The United Nations office for Asia, based in Bangkok, has begun a study to select the best three or four designs and to promote them by supporting commercial manufacturing. The Philippines has asked the US for $2 million to help select a cheap ''alternative cooking device'' and start up production and promotion. Ten different stoves have been tested at a Manila energy lab, where inventors file such claims as ''I cooked rice in just 13 minutes.''
The leader appears to be the ''bioflame'' stove, designed by Dr. Ernesto Lazado of the University of the Philippines. Dr. Lazado claims the bioflame doubles the heat collected from fuel, which can consist of rice-hull briquettes, and reduces problems of kindling, smokiness, radiant heat, and ash disposal. He claims at least 800 have been sold.