Points of Interest | Green Energy News

February 1, 2004 – Vol.8 No.45

POINTS OF INTEREST.

A weekly collection of websites worth visiting.

Here’s a wild statement with nothing to back it up but a gut feeling.

American homeowners will change the way they consume energy when total home energy systems - devices that would provide 100-percent a home’s heat, hot water, power and air conditioning - sell for $5000 or less, can be installed easily in existing homes, and have a service life of 25 -30 years.

And, of course, those systems would be clean and green.

When all that low-cost, clean and efficient technology is available homeowners will buy them by the millions each year.

But which technology will it be? Fuel cell? Solar thermal and electric systems? Conventional-engined combined heat power generation systems operating on natural gas or propane? Microturbine?

Probably, for now, only the conventional-engined system could come close in price. (It’s time-tested technology, after all.) But what else, with more development and mass production could be possible?

The good Reverend Robert Stirling’s 1816 invention.

Stirling cycle engines use expanding hot air and contracting cooler air to move a piston (or a number of them). Thermal energy is supplied externally and any source of heat can be used, even the rays of the Sun. (Toy Stirling engines can run off the heat of your hand.) External combustion makes them run cleaner and quieter than internal combustion engines.

Currently the closest to having a Stirling-powered total home energy system is Whispergen of New Zealand. The company is now selling direct current (DC) units for marine applications, but an alternating current unit (AC) unit for homes does not yet have a launch date for full scale marketing and sales. But even when it is available it will provide only a portion of a home’s energy needs. The Whispergen unit will look a lot like a kitchen appliance and could be installed there.

Hot on Whispergen’s heals is Microgen which plans a similar Stirling cycle product that could be installed next to the washing machine or refrigerator.

And the Stirling Technology Company has a number of products listed in its web site, including ones that could be used for home power and others that have run on solar energy and biomass. But no mention of if and where these products are available.

STM Power has readily available Stirling-engined combined heat and power sets, but have a 55-kilowatt electric output, much more than needed for the average home. The company’s products have been used in landfill gas energy recovery operations. The company mentions that its engines can be powered by solar energy at less cost per kilowatt hour than photovoltaic solar.

Visit Whispergen at http://www.whispergen.com/ , Microgen at http://www.microgen.com/ , Stirling Technology Company at http://stirlingtech.com/ and STM at http://www.stmpower.com/ .