How exactly does geothermal heat power work? – Well, glad you asked.
It’s time to dig into a less talked about-but-powerful source of renewable energy.
While it’s hard to miss a massive solar array or a field full of wind turbines, so much of the action with geothermal energy happens out-of-sight that it tends to not generate as much love as its buzzier brothers in the renewable energy landscape.
And that’s too bad, because geothermal energy is pretty awesome. It takes the natural functions of the Earth and puts them to great use heating homes, creating electricity, and helping to propel the global shift from the dirty fossil fuels driving climate change to renewables.
But how? It’s time to dig into a less talked about-but-powerful source of renewable energy. Read on as we tackle some of the most common questions about geothermal.
WHAT IS GEOTHERMAL ENERGY?
If you were to dig a big hole straight down into the Earth, you would notice the temperature getting warmer the deeper you go. That’s because the inside of the Earth is full of heat. This heat is called geothermal energy,” the EPA explains in itsStudent’s Guide to Global Climate Change.
That’s the gist: When we talk about “geothermal,” we’re talking about tapping into the heat energy contained in the rock and waters of the Earth’s crust.
WHAT IS GEOTHERMAL ENERGY USED FOR?
Geothermal energy is largely used in two distinct ways – to heat homes and other buildings or to create electricity.
The first is the best-known and easiest to understand. Geothermal heat pumps transfer the moderate heat found not far below the Earth’s surface into homes and buildings through a looping pipe system.
When it’s cold outside, the fluid in the pipes warms as it travels through the stretch of pipe buried underground, where temperatures in the upper 10 feet of the Earth remain at a constant 50 to 60 degrees Fahrenheit. The system then carries the now-warmed fluid into a home or building, where the geothermal unit uses it to heat air circulated through your home via a standard duct system.
Some geothermal systems also circulate the fluid directly as sub-floor radiant heat, aka a series of pipes that have been laid beneath your flooring.
(An inversion of this process can be used to cool your home in the summertime, too.)
There are a few more moving parts to a geothermal power plant. These plants tap into the much higher temperatures deeper inside the planet to generate electricity.
This is typically done by pumping very hot water under high pressure from as deep as one or two miles underground. Once the water reaches the surface, the pressure drops, causing the water to turn to steam. That steam then turns a turbine that is connected to a generator, producing electricity.
If this sounds confusing, just imagine a geyser like Old Faithful spouting steam and hot water out of the earth, only here all that steam generates electricity. It’s more than just an analogy – according to the US EPA : “Deep geothermal technologies harness the same kind of energy that produces geysers.”
One key difference between natural geysers and geothermal power plants, though, is that these plants usually recycle the fluid pumped to the surface to use again.
It works like this. Plants often gather the steam that passes through turbines in a cooling tower or some other capturing unit, where it cools off and condenses back into liquid water. Then, they pump this water back into the Earth, so it can warm back up and begin the whole process again.
The whole article: https://www.climaterealityproj…