Good News in Geothermal
With all the buzz in the renewable energy arena swirling around the ever-increasing cost-effectiveness of solar and wind, many of the other flavors of clean energy go wanting for attention.
Geothermal, the form of energy that uses the heat from deep inside the Earth and converts it to electricity, has been one of the principal casualties along the way. Having said that, Ormat Technologies, the world leader in geothermal (a company whose spokesperson I interviewed for my first book: Renewable Energy – Facts and Fantasies) has never shown the most remote sign of giving up. Unimpaired by the inherent high risks associated with drilling through the hardest matter on the planet, the company stays tightly focused on its mission to provide low-cost base-load electricity from this perfectly clean source.
And just yesterday, good news. The company’s commercial plant in Kenya just brought online another 29 MW to boost the total to 140 WM–many months ahead of schedule.
Bringing electricity to the developing world from any source needs to be one of our civilization’s top priorities, since electrical power is the gateway to education, prosperity, and good healthcare. In particular, educated women don’t have 15 children; they have stronger, more productive, and smaller families, an important ingredient in stemming the exponential population growth in these regions.
Surely it would be reasonable to continue research on geothermal energy. Just how practical it would be on a large scale is unclear. It may well be practical in a few locations even if it is not practical on many places. It seems to work well in Iceland but that is a special situation.
This seems like a great idea in principle, I’m going to go Google it and learn some more about it. Would this really be an affordable option, as Solar and Wind are?
We have just bought a Solar Thermal system for our house and it works great, just waiting to see how much of a difference it makes to our bills too.
The potential of geothermal is woefully under-recognised.
Geothermal is baseload power, and could potentially generate power anywhere in pretty much unlimited quantities. Provided there is enough available water, there is also minimal enviromental impact from a well run project – you just need to drill down deep enough, create a heat exchanger, and pass water through the heat exchanger (CO2 or carbonated water could be used as an alternate heat transfer fluid with the advantage that any fluid list in the process is geologically sequestered.)
To boost the use of geothermal, research needs to concentrate on
1. Improving understanding of geothermal resources – with better knowledge of the geothermal reservoirs, less dry wells will be drilled, and the most economic drilling locations can be identified.
2. New drilling techniques especially non contact drilling methods such as thermal spallation (shattering rock with heat shock), and methods for reducing bore size in the exploratory phase. (A smaller drill hole costs less!)
3. Wider use of low temperature reserves for thermal rather than electrical use – district heating, process heat etc.
4. Added value – hybridisation can in some cases make better use of the available heat. CSP or gas can be used to boost the temperature of the resource improving the Carnot efficiency of power generation.
5. Identifying and monetising secondary products – some geothermal brines contain useful or valuable salts such as Lithium in the Salton Sea area.
Excellent. Thanks for this very pithy summary of the subject.