Overview

A microturbine, ^[2] as the name suggest, is a small gas turbine. Research on microturbines predicts that affordable commercially available models eventually will shrink to thumbnail-size and become PTs, or personal turbines, much the way large room-sized computers became PCs.

For the time being "affordable, commercially available" microturbines are about the size of a household refrigerator and run on a variety of waste (like wood waste, biomass, or methane rising off landfill) and low BTU gases. Microturbines require a recuperator to develop anywhere close to an efficiency (about 40%) that makes them commercially viable. Commercial microturbines deliver from 50 kW to 500 kW most commonly and can power small schools, remote process plants, and small industry. A tie in to the local grid, if grid access is available, for backup power can be provided.

Hybrid is the name given to a gas turbine in conjunction with a fuel cell. Fuel cells are given some space in this chapter because of their ability for application in concert with gas turbines. In contemporary work, the gas turbine in a hybrid system is most commonly a microturbine. The hybrid then results from the partnership of a heat engine and a nonheat engine (two different cycles). Because the term combined cycle is reserved for the combination of two different heat cycles (gas and steam turbine cycles), the gas turbine-fuel cell is called a hybrid