Electricity from Heat | Green Energy News

August 6, 2006 – Vol.11 No.20

ELECTRICITY FROM HEAT: THE PURSUIT OF NEW TECHNOLOGIES.

Hydrogen proponents like to proclaim that it is the ultimate solution for energy. Hydrogen is clean and abundant. It’s the most common element in the Universe and when combined with oxygen to release energy the byproduct is only water.

While hydrogen is certainly common, it is not universal, it is not everywhere in the Universe. However electrons are. (As far as we know.) Hydrogen is only one element of dozens. Every element has electrons spinning about its core nucleus.

If electrons are more abundant than hydrogen shouldn’t we be seeking more ways to harvest electrons than hydrogen?

Over the centuries man has devised a number of ways to grab electrons, make them flow, and put them to work efficiently

We use moving magnets to coerce electrons to flow where we’d like: We call these devices generators or dynamos.

We’ve learned how to grab electrons away (momentarily) from metals as they oxidize: We call these devices electrochemical batteries.

We’ve learned how to use photons of light to knock electrons off metals: We call these devices solar or photoelectric cells.

While there is considerable investment, interest and knowledge in the technological development of all of the above, only a comparatively small amount of interest is focused on another way to generate electrons: heat.

To some extent we already use heat to release electrons from metals, and have done so for decades. Devices conceived exclusively to generate electricity directly from heat - thermoelectric generators - are available but rare. (Global Thermal Electric makes such a generator.) The thermoelectric principle is also commonly used. Homeowners who have a tank-type gas hot water heater with a pilot light also own a thermoelectric device. It’s a heat-to-electricity safety device called a thermocouple which shuts off gas to the pilot light should it be blown out.

But work on better thermoelectricity does amble on. Eneco of Salt Lake City, Utah has been developing a Thermal Chip, a kind of semiconductor to convert heat (any source of heat ) to electricity. The chip, they say, has an energy density 5 times that of state-of-the art lithium batteries, provided a source of heat is available.

Fortunately heat is available from the Sun, sources of combustion or free waste heat. The heat of the Sun could be used to directly generate electricity from a Thermal Chip, or perhaps waste heat from a device such as a car engine or a computer could be converted to electricity then channeled back to increase its efficiency.

Eneco says that a thermal electric generator would be 10 times cheaper using their technology than competing devices (such as from Global Thermal Electric).

Visit Eneco at http://www.eneco-usa.com/ and and Global Thermal Electric at http://www.globalte.com/ .