During one process of mining coal, methane is removed from the coal seam before the coal is mined. This methane is collected underground, piped to the surface, and exhausted to the atmosphere as a waste by-product of the mining process. An electrical power generation system was assembled to demonstrate utilization of this energy source. An 800 kW gas turbine generator with attendant compression and electrical equipment converted 200,000 standard cubic feet per day of methane to about 250 kWh. This electrical power was utilized by a mine surface load consisting of a 100 hp air compressor and a 300 hp mine ventilation fan. Power generated represented about 25% of the total energy used in all the mine ventilation systems or about 5% of the total underground mine electrical requirements. The main conclusions of the work performed is that low Btu gob gas in the range of 100 to 400 Btu/ft/sup 3/ can be combusted successfully in a diffusion flame system. The efficiencies that can be achieved are high and in general stability is adequate. Both the efficiency and stability range achieved were sufficient to indicate that a gas turbine could be operated with such fuels over a normal operating cycle. One problem that was noticed during earlier investigations is that because of the low energy content of the fuel, heat losses in the combustor can significantly affect performance, particularly stability. In general such combustion systems should be maintained as near adiabatic as possible and should operate with as high a wall temperature as is possible. Further research and development will be required of any scaled combustion system before it could be considered a suitable candidate for engine installation.