Prime Movers and Electrical Generators: A Summary
The following table compares the two main types of CHP package and provides details of typical capacities and dimensions.
CHP Packages: outline data | |||||||
| Gas-engine CHP | Small-scale gas turbine CHP | ||||||
| Electrical output | 60kW | 100kW | 300kW | 600kW | 1,000kW | 60kW | 100kW |
| Heat output | 115kW | 130kW | 430kW | 880kW | 1,300kW | 100kW | 150kW |
| Fuel consumption | 215kW | 310kW | 990kW | 1,950kW | 3,000kW | 280kW | 350kW |
| Electrical efficiency | 27.9% | 32.3% | 30.3% | 30.8% | 33.3% | 21.4%¹ | 28.6% |
| Heat efficiency | 53.5% | 41.9% | 43.4% | 45.1% | 43.3% | 35.7% | 42.9% |
| Overall efficiency | 81.4% | 74.2% | 73.7% | 75.9% | 76.6% | 57.1% | 71.5% |
| Package length (metres) | 2.9 | 2.9 | 4.0 | 6.5 | 8.0 | 2.0 | 2.9 |
| Package width (metres) | 0.8 | 1.3 | 2.0 | 3.5 | 4.0 | 0.9 | 0.9 |
| Package height (metres) | 1.8 | 1.95 | 2.4 | 2.6 | 3.5 | 1.6 | 1.9 |
| Package weight (tonnes) | 2.5 | 4.0 | 8.0 | 12.0 | 16.0 | 1.0 | 2.0 |
| ¹Small-scale gas turbines with recuperators have higher electrical efficiencies - typically 26-28%. | |||||||
The table below summarises prime mover/electrical generator characteristics.
Summary of prime mover/electrical generator characteristics | ||||
| Type of plant | Typical output range | Typical fuels | Typical heat to power ratio | Grade of heat output |
| Gas engine | 50-1,000kW | Natural gas, Landfill gas, Biomass or Mine gas | 1.5:1 | Low or Low/High |
| Small-scale gas turbine | 30-1,000kW | Natural gas, Landfill gas, Biogas or Mine Gas | 1.5:1 (up to 3:1 for some units) | Low or High |
