Carbon Capture and Storage Technologies

Engineers are developing machines to remove carbon dioxide from the air to help fight climate change. These technologies offer new tools alongside natural solutions like planting trees. Carbon capture technology works in two main ways to reduce the amount of CO2 in Earth's atmosphere.

The first approach is called carbon capture and storage, or CCS. This method captures CO2 directly from smokestacks at factories or power plants before it escapes into the air. Special filters and chemical solutions trap the carbon dioxide as it rises from burning fossil fuels. Once captured, the CO2 is compressed into a liquid form. Workers then pump it deep underground into rock formations where it can stay trapped for thousands of years. Some companies also use captured carbon to make products like concrete or synthetic fuels.

The second approach is direct air capture, or DAC. These machines are more ambitious because they pull CO2 straight from the open atmosphere. Giant fans draw air through special filters that grab CO2 molecules. The process works similar to how a sponge soaks up water. Scientists then heat the filters to release the concentrated CO2 for storage or use. The Orca plant in Iceland, which started operating in 2021, can capture about 4,000 tons of CO2 each year. That equals the annual emissions from roughly 870 cars.

Evidence shows these technologies can work, but they face significant challenges. Both methods require large amounts of energy to run. CCS systems can use up to 30 percent of a power plant's energy output. Direct air capture machines need even more energy because atmospheric CO2 is much less concentrated than smokestack emissions. The costs remain high too. Capturing one ton of CO2 through direct air capture can cost between $600 and $1,000. Together, all carbon capture facilities worldwide currently remove less than 0.1 percent of global CO2 emissions each year.

Carbon capture technology matters because it may help reduce atmospheric CO2 levels in the future. Scientists explain that these tools could be especially useful for industries that are hard to clean up, like cement production. However, experts emphasize that carbon capture is not a substitute for reducing fossil fuel use. The technology works best as one part of a larger climate solution that includes renewable energy and energy efficiency.

Interesting Fact: If we tried to capture all of humanity's current CO2 emissions using today's direct air capture technology, we would need machines covering an area larger than the entire country of India.