NPR: NPR look at two different techniques for generating power without having to worry about CO2 emissions. Richard Harris visits Iceland to see how the country uses 'hot rocks' to generate power. Iceland is a geo-active area in which hot magma, usually ten-of-miles deep under the Earth, is close to the surface. Engineers pump water close to the magma, turning it to high pressure steam which is used to run turbines and supply hot water to the surrounding towns. One accident at the plant led to a 50m deep crater known as 'Man's Hell', a reminder of the dangers of geothermal operations. Meanwhile Greg Allen visits a prototype turbine that will be dropped into the Gulf Stream. The Gulf Stream has a strong and predictable North-East current about 15 miles off the coast of Florida, making it ideal for providing a reliable power source for potentially one-third of Florida's needs. As well as using turbines to generate power, researchers at Florida's Atlantic University are also investigating the thermal differences between the warm surface water and the deep cold water near the ocean floor. Exploiting these ocean thermal differences remains a goal of a number of university labs worldwide.