Combined heat and power (CHP) systems to squeeze more energy from fossil fuels

Posted on April 16, 2007
Filed Under Technology | Leave a Comment

We all hear about the dangerous of global warming on a daily basis and we all hear about how we cause it by not being careful about our usage of energy most of which we obtain from coal and fossil fuels. Most of the blame goes to our oil hungry automobiles which in North America at least have gotten larger and less fuel efficient over the last 20 years. We hear about many alternatives to curbing our desire for fossil fuels including biofuels, fuel cells, nuclear, solar, wind, and finally electrical power delivered using chemical batteries. All of these technologies are far from being affordable and mainstream in the next few years. Until such technologies become common, we must figure out ways to get the most energy possible out of fossil fuels. Combined heat and power systems might provide a way to get more energy from fossil fuels paving the way for alternative energy sources.

Much of the energy generated in power plants which are much more efficient than say the internal combustion engine found in cars is lost as waste heat at the plant and while traveling over power lines. Estimates put the lost energy to 2/3rds of the energy stored in fossil fuels. Combined energy and heat systems want to move the power plant in your basement in effect replacing your furnace with a system that generates not only heat but also electricity and hence saving some of the energy lost during power transfer over the power lines. Systems of this type have been used to power hospitals, universities and large factories and now due to a new technology called micro-CHP could power our homes.

Micro-CHP systems consist of an internal combustion engine and a furnace. The engine drives a generator to produce electricity, and the heat created in the process goes to the furnace via a heat exchanger module. You can run a micro-CHP system using oil, coal or natural gas.

Micro-CHP systems are currently being installed in U.S. homes. One of the main suppliers is Climate Energy in Medfield, Massachusetts. The system can deliver 1.2-kilowatts of energy. Not all homes are suitable for a micro-CHP system; the main market for micro-CHP in North America would be homes that require more than 4000 heating hours per year. The system is most efficient when there is high demand for heat which would be in areas of the continent that have long and cold winters. One of the advantages of having a micro-CHP installed is that during low demand hours for electricity such as at night, owners can sell energy to the local utility company. Installing a micro-CHP system is rather expensive at the moment but owner could pay it off in 2 years and save up to $500 per year after that.

Bookmark: