The deeper you go into the earth’s core, the hotter it becomes.
Some of this vast energy is already harnessed by geothermal power plants which use steam from heated water deep underground to drive turbines and generate electricity.
Geothermal electricity plants are typically built near tectonic plate boundaries, where high temperatures can be accessed much closer to the earth’s surface.
But recent advances in technology mean that disused oil wells and even operating oil fields could be used to generate geothermal electricity.
earthrise can be seen each week at the following times GMT: Tuesday: 2230; Wednesday: 0930; Thursday: 0330; Friday: 1630; Saturday: 2230; Sunday: 0930; Monday: 0330; Tuesday: 1630.
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