Figure 5.4 shows that a typical CHP system can reduce energy requirements by
close to 45% compared to separate production of heat and power. For every
100 units of input fuel, CHP converts 85 units to useful energy, of which 20 are
electricity and 65 are produced as steam or hot water. Conventional separate heat and
power production generates approximately 40 units of electrical energy from
100 units of input fuel.
By increasing energy efficiency, CHP also significantly reduces emissions of
criteria pollutants such as NO x and SO 2 and non-criteria greenhouse gases such as
CO 2 . CHP can provide environmental benefits as part of an economically attractive
investment; the technology can significantly reduce emissions and compares favorably to advanced low emission central station technologies such as gas-fired combined cycle systems (US Environmental Protection Agency Combined Heat and
Power Partnership 2002).
In a restructured power market, CHP and other on-site generation options can
provide grid support to the local distribution utility. On-site generation can offer
ancillary benefits to the grid including:
• Voltage and frequency support to enhance reliability and power quality.
• Avoidance or deferral of high costs, long lead times, and transmission and
distribution upgrades.
• Bulk power risk management.
• Reduced line losses and reactive power control.
• Outage cost savings.
• Reduced central station generating reserve requirements.
• Transmission capacity release.
CHP offers enhanced reliability for customers, as well as operational and load
management flexibility, the ability to arbitrate electric and gas prices, and energy
management techniques including peak shaving and thermal energy storage. The
value of these benefits depends on the characteristics of the individual facility,
including energy use and prices, load profiles, and electric rate tariffs.
The prime mover technologies of CHP systems are summarized below.
5.3 Prime Mover Technologies for Combined Heat
and Power
5.3.1 Gas Turbine
Gas turbines are an established technology available in various sizes, ranging from
several hundred kilowatts to over several hundred megawatts. Gas turbines produce
high-quality heat that can be used for industrial or district heating requirements.
Alternatively, this heat can be recuperated to improve power generation efficiency or
used to generate steam to drive a turbine in a combined-cycle plant. Gas turbine
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H. Ren et al.
close to 45% compared to separate production of heat and power. For every
100 units of input fuel, CHP converts 85 units to useful energy, of which 20 are
electricity and 65 are produced as steam or hot water. Conventional separate heat and
power production generates approximately 40 units of electrical energy from
100 units of input fuel.
By increasing energy efficiency, CHP also significantly reduces emissions of
criteria pollutants such as NO x and SO 2 and non-criteria greenhouse gases such as
CO 2 . CHP can provide environmental benefits as part of an economically attractive
investment; the technology can significantly reduce emissions and compares favorably to advanced low emission central station technologies such as gas-fired combined cycle systems (US Environmental Protection Agency Combined Heat and
Power Partnership 2002).
In a restructured power market, CHP and other on-site generation options can
provide grid support to the local distribution utility. On-site generation can offer
ancillary benefits to the grid including:
• Voltage and frequency support to enhance reliability and power quality.
• Avoidance or deferral of high costs, long lead times, and transmission and
distribution upgrades.
• Bulk power risk management.
• Reduced line losses and reactive power control.
• Outage cost savings.
• Reduced central station generating reserve requirements.
• Transmission capacity release.
CHP offers enhanced reliability for customers, as well as operational and load
management flexibility, the ability to arbitrate electric and gas prices, and energy
management techniques including peak shaving and thermal energy storage. The
value of these benefits depends on the characteristics of the individual facility,
including energy use and prices, load profiles, and electric rate tariffs.
The prime mover technologies of CHP systems are summarized below.
5.3 Prime Mover Technologies for Combined Heat
and Power
5.3.1 Gas Turbine
Gas turbines are an established technology available in various sizes, ranging from
several hundred kilowatts to over several hundred megawatts. Gas turbines produce
high-quality heat that can be used for industrial or district heating requirements.
Alternatively, this heat can be recuperated to improve power generation efficiency or
used to generate steam to drive a turbine in a combined-cycle plant. Gas turbine
112
H. Ren et al.