Geothermal Heating

Hot Dry Rock Geothermal Energy is an imporant aspect of Geothermal Energy. As you know, there are quite a few ways to utilize geothermal energy, but one of the most recent developments that could profoundly impact the use of geothermal power in North America is the use of Enhanced Geothermal Systems (EGS) to rejuvenate old pockets of superheated steam with new water introduced onto what some call "hot, dry rocks." The potential for this to create a new source of electricity in some of the most barren areas of the usually rather arid, southwest United States, is vast.

These rocks are actually underground caverns with magma flowing beneath them, heating the rocks to very high temperatures, even long after any ground water that might have been contained once has been evaporated off. Perhaps there was no water in the first place - either way, injecting water into these caves gives that heat energy something it can perform "work" upon, heating and changing the state of the water from liquid to steam.

Before a hole is drilled to let the steam escape, these newly watered areas are allowed to settle in for a little while. This increases the size of the reservoir and allows existing cracks to be broken apart and increase the size of the cavity to be filled with water. Often the effective area for the water to flow into is increased greatly when allowed to break up the nearby rocks with the temperature differential, like pouring boiling water on ice cubes, existing fissures blow apart and open up new chasms.

As such, this operation is very delicate and much study goes into these sites before the first drop is pumped in. Once this process is complete and the volume of the cavern seems to have stabilized, a hole may be drilled to release the super-heated steam under tremendous pressure. This is usually suitable to run large electric turbines that produce many megawatts of power, as long a the water keeps coming.

Of course, getting water to the desert is no small feat, but thankfully, salt water may be used, allowing pipelines from nearby marine areas to be utilized. Sometimes the steam that is output is condensed when done and sent back down for another round instead of letting it all escape to the air, however, the end result is the same, since that vapour is more likely than not to fall over an ocean area.

It is thought that the use of these hot, dry rocks for geothermal energy will increase the output of geothermal energy in the US by several measures. As long as there exist the resources to build power plants atop these otherwise spent caverns, production could be better than competitive with imported petroleum and domestic coal in a few years. Look for increased spending in the governmental and entrepreneurial sector to bolster the use of EGS systems in power and industrial industries.

Geothermal Heating |