Iceland is famous for its beautiful scenery, midnight sun, and aurora borealis in the winter, but beyond beauty, there’s a technology reason to take interest in Iceland. 100% of its electricity needs are generated by green energy since 2012, and this is accomplished through a combination of hydro energy and geothermal heating. Aiding in this achievement is a new 300–megawatt geothermal power plant in Hellisheiði that actually consumes more CO2 than it produces. As a result, it creates negative emissions and cleans the air as it produces electricity for the people of Iceland.
How It Works: Turning CO2 into Stone
The process by which the plant cleans air sounds like something between a science-fiction story and magic. To start, a large collection of fans suck in air into a Climeworks patented filter. The filter is then heated to extract pure carbon dioxide. From there, the carbon dioxide is bound to water molecules and pumped underground to a depth of 2,300 feet below ground level. At that depth, the carbon dioxide interacts with the basalt to form limestone. In this form, the CO2 can be safely stored underground without fear of reentering the atmosphere for potentially millions of years. Of course, the petrification of the carbon dioxide is not instant, but it reduces the timeframe from centuries to approximately two years.In effect, the CO2 is extracted from the air and turned to stone beneath the Earth.
Before this technology is hailed as a solution to all our energy issues, it should be noted that the efficiency of the technology is not yet up to par to be widely used in all power plants. The plant generates a third of the power that a comparable coal-based power plant would generate. Furthermore, geothermal power plants produce far less CO2 to begin with at roughly 3% compared to coal plants.
The source of most electricity is not coal or natural gas. It is actually heat. Coal and natural gas are burned to create heat, and that heat is converted into energy and electricity. Geothermal power simply captures heat from a natural source, the planet itself. The heat is found by drilling water or steam wells into the Earth.
Water deep beneath the Earth’s surface is heated by the core and pressure of the dirt and rock around it. A geothermal plant collects water out of these geothermal reservoirs flows through the power plant and then back down into earth, back down into the reservoir to be reheated and reused.
A Step in the Right Direction
It’s important to recognize that carbon capturing technology is still in its nascent stages. At this time, the cost pushes the solution out of viability. Still, it’s impressive to see a power plant of any kind create cleaner air while also producing renewable energy. If this technology can continue to advance and become cost-effective, it should find wide support.
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