Geothermal Energy: The most powerful of all natural renewables
I couldn’t help but notice one shortcoming of the CM-CrashCourse was not addressing GeoThermal Energy.
Geothermal power requires no fuel, and is therefore virtually emissions free
and insusceptible to fluctuations in fuel cost. And because a
geothermal power station doesn’t rely on transient sources of energy,
unlike, for example, wind turbines or solar panels, its capacity factor can be quite large; up to 90% in practice.
It is considered to be sustainable
because the heat extraction is small compared to the size of the heat
reservoir. While individual wells may need to recover, geothermal heat
is inexhaustible and is replenished from greater depths. The long-term
sustainability of geothermal energy production has been demonstrated at
the Lardarello field in Italy since 1913, at the Wairakei field in New
Zealand since 1958, and at The Geysers field in California since 1960.
Geothermal has minimal land use requirements; existing geothermal
plants use 1-8 acres per megawatt (MW) versus 5-10 acres per MW for
nuclear operations and 19 acres per MW for coal power plants..
It also offers a degree of scalability: a large geothermal plant can
power entire cities while smaller power plants can supply more remote
sites such as rural villages
A 2006 report by MIT, that took into account the use of Enhanced Geothermal Systems
(EGS), concluded that it would be affordable to generate 100 GWe
(gigawatts of electricity) or more by 2050 in the United States alone,
for a maximum investment of 1 billion US dollars in research and
development over 15 years.
The MIT report calculated the world’s total EGS resources to be over 13,000 ZJ.
Of these, over 200 ZJ would be extractable, with the potential to
increase this to over 2,000 ZJ with technology improvements –
sufficient to provide all the world’s present energy needs for several millennia
taken from wikipedia
Interestingly enough, this was mentioned in the MSM on NBC Nightly News this evening:
One may regret indeed that not much of an effort seems to be going into Enhanced Geothermal Systems R&D. Google phylantropic side organisation has earmarked $10 Million in research fund for EGS ………very little when one appreciates all the research that remains to be done before the technique becomes well controlled. Without going into details one should go into the excellent 2006 MIT report refered above in the Wikipedia presentation to appreciate all that remains to be done. Yet Enhanced Geothermal is by far the most appropriate of the renewable alternate energy sources on whihc to rely for the centuries to come. It is implementable almost everywhere (provided you drill deep enough !), this garantees energetic independance to the users. As mentioned its footprint is minimal. There are no poluting effluents generated by the technique…i.e. it is absolutely clean and can be used either directly (i.e. through heat exchangers) to central heat buildings, towns or cities or…indirectly transformed into eletricity (through heath exchangers followed by turbine, assuming the combination of pressure temperature of the collected vapor are adequate).
One may thefore regret that oil @ 51$ a barrel is too cheap to prompt investment research into EGS at the level it deserves. One obvious solution that should be put into effect is a large carbon tax whihc would generate the finds necessary to finance that research and assist in cleaning up the environmental/social mess that the oil and gaz era will be leaving behind for the generations of living creatures (man being one of those) to come.