Engines? Turbines? Both?
Choosing Power for Combined Heat and Power Projects
by Michael A. Devine
Caterpillar, Electric Power Division
Gas Product Marketing Manager
Today’s market conditions increasingly favor distributed generation fueled by natural gas and other gaseous fuels, and the addition of heat recovery from the generating source makes the economics all the more attractive.
Developers of distributed generating systems have a choice between two primary power sources: gas reciprocating engines and gas turbines. Both are proven worldwide in thousands of cogeneration (combined heat and power, or CHP) installations. Over the years, both technologies have steadily improved in efficiency, reliability, emissions performance and operating costs – and they continue to do so.
Neither technology is “better” than the other. Instead, each has attributes that make it the most suitable for specific conditions of fuel type and quality, electric and heat load profile, physical space, altitude, ambient conditions, and others. In fact, there are applications where reciprocating engines and turbines working in concert can provide the ideal levels of electrical reliability and efficiency, thermal output, load-following capability and, ultimately, return on investment.
Beyond its economic benefits, gas-fueled CHP can help organizations live up to their sustainability, carbon-reduction and energy-conservations goals. It can also help facilities qualify for green-building certification under rating programs such as...the U.S. Green Building Council’s Leadership in Energy and Environmental Design (LEED) program.