Slashdot Mirror
Iceland Eyes Liquid Magma As Energy Source
An anonymous reader writes "Scientists in Iceland have been studying and utilizing the power of geothermal wells for years. In 2009 one such study hit a standstill when a group ran into magma halfway into their dig. The roadblock has become a blessing in disguise, as recent research has shown that the magma can act as a potent new source of geothermal energy powerful enough to heat 25,000 to 30,000 homes."
As opposed to what? Solid magma is more commonly called "rock".
Please, stop cooling magma. No more viscous magna means no more earth magnetic field, hence no more magnetic shield, ie no more life.
Please, don't dig for geothermic energy. Leave alone our earth kernel.
Now let's do some math.
Mass of the earth: 5.9*10^24 kg. Apart from a very thin shell on top, most of that is at a couple of thousand degrees kelvin.
Magma has a much higher specific heat, but let's be conservative and assume all of earth has the same specific heat as iron, or about 460 J/kg
Cooling the earth by a single degree will release about 2.75*10^27 joules
The total world energy consumption from all sources in 2008 was estimated at 4.75*10^20 joules.
At that rate, cooling the interior of the earth by a single degree would power the entire world for 5,789,473 years.
And that's assuming the earth doesn't continue to generate heat from radioactive decay, tidal forces, friction etc.