The world built more coal power plants in the past decade than any decade ever before, and existing coal plants may spew out 300 billion tons of carbon dioxide before they’re retired. One way to capture those emissions, according to new research, might be tiny, droplet-sized capsules made from a common household cleaner–baking soda.
Unlike current carbon capture technology, which usually uses harsh chemicals and creates toxic waste, the new process wouldn’t cause new problems.
“If we’re going to have an impact on a global scale, we have to remove a lot of carbon dioxide from a lot of factories and a lot of power plants,” says Roger Aines, a senior scientist at Lawrence Livermore National Laboratory, and lead author of a new study describing the research. “We’re going to have to use a lot of whatever method we’re using. If the chemicals involved in that involve a whole lot of manufacture themselves, and have environmental challenges, then we’re already behind the eight ball.”
The new microcapsules, by contrast, are simple to make and safe. “We’re using chemicals that are naturally occurring and readily available,” Aines says. “So you don’t have a big industrial process involved just to start your big industrial process.”
The method is also likely to be significantly cheaper than current techniques, in part because less new infrastructure needs to be built. Essentially, a power plant or factory would just have to hold a giant pile of the microcapsules. “What I envision is something that looks like a McDonalds ball pit, only it’s much bigger, and it has little tiny balls in it,” Aines explains.
After the microcapsules suck in emissions, they can be heated to release the carbon dioxide for use or for storage underground. Then the capsules can be used again.
The process works for any stationary source of pollution, but not for something like moving vehicles. “Moving probably doesn’t work, because it turns out the carbon dioxide weighs a lot, and it’s hard to carry it around,” says Aines. “Power plants are what the Department of Energy is focused on, but I’d like to also see this technology applied in places like breweries that are emitting carbon dioxide and want to have a smaller carbon footprint.”
At power plants, the technology can be an interim solution until there’s a full shift to renewable energy. “Right now, we’re emitting on the order of five gigatons of CO2 in energy production, and we need to start knocking that down,” Aines says. “Eventually we’ll get to the point where a renewable energy portfolio can handle it all, but not immediately.”
In around five to 10 years, the technology might be ready for use. Aines is optimistic that it can quickly gain acceptance–both because it’s cheap and easy for power plants, and something that the public will likely support.
“The thing that drives me is the idea that people are going to find it easier to accept,” he says. “The environmental impact is well understood by people today. Both the bicarbonate and shell are both things you have in your kitchen right now.”