The World in 2030

The World in 2030 231
It may seem surprising that I describe hydro-energy as only
being ‘fairly green’; this is because methane builds up on
the bottom of the reservoir created by a dam and, when the
water power is released to drive the turbine which produces
electricity, this methane (a very potent greenhouse gas) is
released into the atmosphere. Thankfully, researchers in
Brazil have recently developed a technique 441 which may
help to extract the methane from the bottom of dam basins
and use it for power generation.
Geothermal energy is completely green (harnessing heat
from rocks) but in Europe the only regions which have such
reachable underground heat in any quantity are Iceland and
Switzerland. As the Swiss government points out:
Switzerland is currently world leader when it comes
to the utilisation of geothermal sensors. No other
country in the world has so many in place in proportion
to its surface area!
Sources of hot water below the earth’s surface (aquifers)
can be tapped by drilling, and energy can be obtained
from dry rock layers with the aid of enhanced
geothermal systems technology. At temperatures
above 100°C, these energy sources can be used for
electricity production, while the residual heat can be
utilised for heating purposes. 442
Iceland is planning to sell power produced from geothermal
heat to the UK and other European customers, as reported
in The Times in May 2007: