For over 50 years the Chinese have struggled to develop and
diffuse biogas technology. At present, China has about 5 million
family biogas plants in working order. Although over 7 million
have been constructed in the past, many of them were poorly
built with inadequate mixtures of earth, sand and lime, This was
mainly because during the 1950s and 1970s "quality" was
sacrificed at the altar of "quantity" which has left a lasting
impression in farmers' minds of digesters never producing much
gas. Today, about 25 million Chinese people use biogas mainly
for cooking and lighting. A further 10,000 largeand medium-size
biogas digesters are working in food factories, wineries,
livestock farms etc. Biogas produced in large enterprises is
transferred to centralized biogas supply stations, biogas motive
power stations (422 with an installed capacity of 5849 HP) or
biogas electric power stations (822 with a total of 7836 kW).
The Bureau of Environment Protection and Energy (1991) estimates
that about 54 per cent of the