"Cogeneration": Recycling Waste to Generate Power

Tag : co-generation power plant
(HealthNewsDigest.com) - Cogenerationalso known as combined heatand power, distributed generation, or recycled energyis thesimultaneous production of two or more forms of energy from asingle fuel source. Cogeneration power plants often operate at 50to 70 percent higher efficiency rates than single-generationfacilities.

In practical terms, what cogeneration usually entails is the use ofwhat would otherwise be wasted heat (such as a manufacturingplants exhaust) to produce additional energy benefit, such as toprovide heat or electricity for the building in which it isoperating. Cogeneration is great for the bottom line and also forthe environment, as recycling the waste heat saves otherpollutant-spewing fossil fuels from being burned.

Most of the thousands of cogeneration plants operating across theUnited States and Canada are small facilities operated bynon-utility companies and by institutions like universities and themilitary. For small cogeneration plantsthose that generateanywhere from one to 20 megawatts of powerbiomass or even methanefrom garbage dumps can be used as a front-end fuel source, butnatural gas is far more common as the primary input.

For instance, Sunnyvale, California-based Network Appliance Inc., acomputer networking company, relies on a one megawatt naturalgas-powered cogeneration system to power the buildings extensiveair conditioning needs, and for back-up power for use during peakdemand times. The company estimates it saves around $300,000 a yearin energy costs thanks to the cogeneration system.

In another example, Illinois-based Epcor USA Ventures operatesthree mid-sized (25 megawatts and up) cogeneration power plants inSan Diego to power U.S. Marine Corps and Navy bases there. Allthree plants work in the same way: Natural gas turbines driveelectrical generators that in turn exhaust hot gases. These arethen captured to drive a steam generator hooked into the basescentralized heating and cooling systems. Since the systems generatepower to spare, Epcor is talking with area companies about kickingin for a share of the steam to keep their energy bills and carbonfootprints in check.

Cogeneration is not limited to stationary power plants. Honda isexploring the use of a specialized automotive cogenerationgenerator designed to improve the overall efficiency of hybridvehicles by recapturing waste exhaust heat from the internalcombustion engine and converting it to electricity to recharge thebattery pack. The idea is still in the research and developmentphase, it could make its way into new cars within a few years,further improving on the already impressive efficiency of hybridcars.

CONTACTS: Network Appliance Inc., www.netapp.com; Epcor USAVentures, www.primaryenergy.com; Honda Motor Company,http://world.honda.com.

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