The heat beneath the earth’s surface has long been considered to be an almost inexhaustible source of energy. Harnessing has been a challenge but the introduction of nanomaterials will lend the efficiency required to use this energy source to generate a reservoir of pollution free electricity.  Read more about Geothermal Power Technology

Even though geothermal industry was being pegged as the next big thing in energy generation about thirty years back the efforts and researches quickly lost steam after it was found that few places had rocks that were hot enough and close enough to the earth’s surface to produce geothermal energy efficiently and economically.

But the scenario has changed drastically with the introduction of nanomaterials which make it possible for the geothermal industry to explore the production of energy at lower temperatures.

Peter Mcgrail, a fellow at the Richland lab says that they stumbled upon an energy producing cycle which would make it possible to exploit geothermal sources for economical power production.

Geothermal Power Technology

Nanomaterials, which are particles one thousandth the width of human hair, were primarily being analyzed for their ability to absorb carbon dioxide. However, for certain nanomaterials that showed poor CO2 absorption capabilities, the team tried to analyze if they absorbed other compounds. It was found that some of these nanomaterials can absorb up to 30 percent of their own weight; a property that would make them efficient for use in the geothermal industry.

It was found that these nanomaterials would be able to hold on to the molecules of gas at much higher temperatures preventing the fluid from flashing to gas till it reaches a higher temperature and pressure.

Production of power in the geothermal industry has several benefits associated with it; the primary advantage is the fact that it is renewable and almost pollution free. Another benefit is the fact that it is a constant source of energy unlike solar and wind power and can provide the steady base load that a power grid needs.

Conventionally two processes were used to generate energy in the geothermal industry. The procedure is standard for both processes water driven into the hot rock bed beneath the earth’s surface has to be heated to 300 degree Fahrenheit or hotter to make electricity generation efficient. However, these hot rocks are theoretically found 5000 feet beneath the surface of the earth but typically these rocks are much deeper. But with the discovery of nanomaterials it may now be possible to use rocks closer to the earth’s surface making the entire process more efficient and economical.

Typically heat from the ground is extracted by pumping water into the ground and   extracting it after it has been heated by the rocks. This water then goes to the heat exchanger to heat liquid and then to vapor to drive the turbines which produce the electricity. If only water is used as the liquid than it has to be at 212 degrees to produce steam.

However in certain segments of the geothermal industry where lower temperatures pose a problem an organic compound like propane is mixed with the water. However, propane flashes to gas at lower temperatures which means that it has low efficiency as far as energy extraction is concerned than water. Both cycles are inherently inefficient according to McGrail.

The technology is still being tested and McGrail seemed confident that if everything goes well it could be introduced for use in the next five years for use in the .

The research is significant because the Massachusetts Institute of Technology, in a technical and economical survey estimated that the geothermal industry could meet up to10 percent of the nation’s energy needs by 2050.