A very small combustion turbine, individually of the size of a refrigerator, that are often packaged in multiunit systems. In most configurations, the microturbine is a single-shaft machine with the compressor and turbine mounted on the same shaft as the electric generator. With a single rotating shaft, gearboxes and associated parts are eliminated, helping to improve manufacturing costs and operational reliability. The rather high rotational speeds vary in the range from 50,000 to 120,000 revolutions per minute (rpm), depending on the output capacity of the microturbine. This high-frequency output is first rectified and then converted to 50 or 60 Hz. Microturbines are capable of burning a number of fuels at high- and low-pressure levels, including natural gas, waste (sour) gas, landfill gas, or propane. ( Picture)
A small turbine that burns fuel (such as natural gas, propane, diesel, ethanol, or biogas) to generate electricity. A heat recovery unit can be added so that the waste heat in its exhaust can also be utilized.