A geothermal plant converts the natural energy found within the Earth into electricity, which can then be transported via power lines for use in both industries and residences. While the technology is new, humans have been using geothermal energy in some form or another for centuries. The energy produced at geothermal plant locations is likely to become even more important in the future as humans continue to search for better and cleaner forms of energy.
The geothermal plant works by bringing heat from beneath the Earth’s surface to the surface. It is then directed to a turbine, which is turned, causing friction. Electricity is created as a result of the friction. Unlike traditional energy plants that may emit carbon dioxide or hazardous nuclear waste, geothermal plants emit very few, if any, harmful byproducts. In most cases, only steam is generated.
This, however, can be accomplished in a number of different ways. There are three basic types of geothermal power plants, each of which utilizes geothermal energy in a slightly different way. While the basic concept may vary slightly depending on the process used, the fundamental premise remains the same. The process used is often determined by the geothermal energy source’s location and type.
A dry steam power plant is the most basic type of geothermal plant. This type of plant uses steam that naturally rises through a channel and then turns the turbine with that steam. Any remaining steam is expelled into the atmosphere, where it condenses into water vapor. Depending on surface conditions, some of it will remain in the atmosphere and some will fall back to Earth.
The flash power plant is another type of geothermal plant. This type of plant extracts heated water from beneath the Earth’s surface and separates it into steam and hot water at the surface. In a closed loop system, the steam is used to rotate the turbine while the rest is reinserted into the Earth.
The other type of system is a binary geothermal system, which has only recently become a viable option. This system heats another liquid that is kept separate from the water using geothermally heated water. Because this other liquid has a lower boiling point than water, it can be heated at temperatures as low as 150°F (65.5 Celsius). The turbine is activated by the steam produced by this other liquid. In some cases, a binary plant and a flash steam plant can be combined to create a hybrid geothermal plant.