Geothermal Systems

Heat from beneath the surface of the earth has been used as an energy source since tens of thousands of years ago. Nowadays, this heat is being used to power relatively simple pumping systems and even large and complex power stations. Known as geothermal energy, this kind of power can be found almost anywhere and is an appealing and sustainable solution to conserve energy and reduce the usage of fossil fuel-based energy.

How geothermal power plants work

Geothermal energy is captured through the use of power plants. The most common way of capturing geothermal energy is to tap into hydrothermal convection systems, in which cooler water seeps into the earth's surface, becomes heated, and rises to the surface. When heated water comes up to the surface, the steam it produces is then captured and used to power electric generators. Geothermal power plants drill holes into rocks to capture steam more effectively.

Geometrical power plants make use of one of three designs, all of which make use of hot water and steam from the ground, utilize it, then return it so that the life of the heat source will be prolonged. In the simplest design, the steam directly goes into a turbine, then through a condenser in which the steam is turned to water. In the second design, very hot water is used by depressurizing it into steam, which is then used to power the turbine.

The third design, also known as a binary system, makes use of hot water by passing it through a heat exchanger, where isobutane-- or another kind of second liquid-- is heated in a closed loop. The isobutane reaches its boiling point faster than water does so it converts more easily into steam which can then be used to power the turbine.