Carbonscape, a company based in Marlborough, New Zealand, has found a new use for microwaves – sequestering carbon dioxide. They have recently developed a way to nuke things like wood chips (and other useless biological wastes) into charcoal. By doing so, carbon dioxide that would otherwise leak into the atmosphere is effectively locked into the charcoal. This charcoal, or “biochar”, is then buried into soil. The benefits of biochar-infused soil include improved soil fertility, fewer soil emissions of greenhouse gases such as methane and nitrous oxide, and the improved ability of soil-dwelling microbes to extract carbon dioxide from the air.
Carbonscape has tested its technology, and is moving to initial batch scale production at its South Island, NZ facility. Once fed with wood debris, each oven can turn 40-50% of it into charcoal, or one ton of charcoal per day, says the company. Of course, the microwave ovens themselves require electricity… which in turn has a carbon dioxide price tag. But Carbonscape claims that, given the amount of carbon sequestered in the charcoal, the overall balance is carbon-negative.
“The application of microwaves to charcoal making is new,” Tim Flannery of Macquarie University in Sydney, Australia - an expert on climate change who is not associated with the company - told New Scientist. “If it increases efficiency in the charcoal-making process it could prove to be a real winner.”
Via New Scientists, New Zealand Herald
Image via Carbonscape