Post by Steve Gardner on Jun 22, 2008 18:26:21 GMT
Since I've been without the Internet, I have taken a few tentative peaks into more mainstream publications - usually with some regret. However, one has proven to be a more interesting read than I'd imagined - The Economist.
They've been very critical of the EU's response to Ireland's rejection of the Lisbon Treaty and they're generally cynical about MP's rather misleadingly upbeat assessment of the economic outlook, with a couple of articles in particular exposing the fragile nature of our economy by pointing out a couple of things that should be happening but are not (I'll post on this tomorrow).
Another interesting article - and the subject of this post - is one about an alternative energy source I'd not heard much about but which is quite promissing - underground heat.
Apparently, The Philippines already generates 25pc of its energy this way, using geysers to turn some of their generators. It's free, inexhaustible and available any time.
The method can, theoretically, be artificially reproduced by drilling two parallel holes in the ground a few hundred metres apart until the rock is hot enough (200C) and then pumping cold water down one of them. The water becomes superheated then turns to steam and is capable of powering a generator due to the force with which it rises back to the surface.
Sounds easy in principle but the is a catch - the best heat-retaining rocks are dry ones, like granite. Unfortunately, these dry rocks are not permeable - an essential requirement for the artificial generation of subterranean energy.
In order to create the necessary permeability (where is doesn't already exist), fissures would need to be forced open, which would be expensive and time-consuming. Unsurprisingly, given these types of rock formations tend to bear no petroleum, there's little appetite for doing the drilling.
Which is a shame, since the estimated rock heat under the US, for example, would be sufficient to power the country at its current rate of consumption for the next 2000 years!
