/ 17 July 2017

New tech to suck carbon out of the atmosphere

Climeworks's carbon filter.
Climeworks's carbon filter.

Humanity is pumping too much carbon dioxide into the atmosphere. It’s trapping heat and warming the planet at a rate that will make life near-impossible for most people by the end of this century. Politicians are dithering when it comes to actually cutting carbon emissions. Right now, this means the world is guaranteed to get 1.5°C hotter this century. Countries on the African continent have repeatedly warned that this will be catastrophic.

With dangerous levels of global warming all-but guaranteed, governments and scientists have put their eggs into one basket: Finding a way to suck carbon out of the atmosphere.

The United Nations Framework Convention on Climate Change, the global body tasked with ensuring something happens to stave off disastrous climate change, says zero carbon can go into the atmosphere by 2050. Half of that will come about thanks to countries reducing their emissions, and factories being more efficient. The other half will come from sucking carbon out of the atmosphere.

Until now, this has seemed a target that could not be met. Earlier this month, however, a company in Switzerland switched on the first commercial plant that takes carbon out of the atmosphere. This is the culmination of eight years of development by the company, Climeworks. Founded by two students, it now has nearly 50 employees and $20-million in funding.

The process itself is relatively simple: Air is sucked into large containers, packed with membranes. Carbon dioxide in the air sticks to these on contact, staying behind after the air is pumped out. The only other byproduct is water.

The carbon is sold to a nearby vegetable garden. Because carbon helps plants grow, the yield on aubergines, cucumbers and tomatoes in its greenhouses is expected to increase by 30%. Other companies, working on the same sort of technology, have partnered with soda companies. Carbon dioxide gives fizzy drinks their fizz and bottlers currently have to get it from plants that specifically create carbon dioxide.

The new plant means that a dangerous source of waste can be turned into a useful product.

But the cost of doing that is still nearly prohibitive. Climeworks’s $4-million plant will remove 900 tonnes of carbon dioxide a year from the atmosphere (South Africa as a whole emits 450 million tonnes a year). At the moment, that process costs the company $600 a tonne.

It plans to have this down to $200 a tonne within five years, and eventually down to $100 a tonne. This will come about as the company scales up its operations, and builds new factories. Climeworks’ grand plan is to remove 1% of global carbon emissions by 2025.

To do that, it will need to use 675 terawatt hours of electricity. Sub-Saharan Africa as a whole consumes 400 terawatt hours a year, while Germany consumes just over 600 terawatt hours a year.

And, besides from cost, this is the big problem with the technology. Most energy around the world is still produced by burning fossil fuels, so carbon will be emitted to power plants that suck carbon out of the atmosphere.

Climeworks’s solution has been to piggyback onto a waste incinerator. This supplies the factory with its energy. That is an insight into industry of the future, where modular factories are built as part of other industries to ensure they do not send carbon into the atmosphere.

Thanks to the need for the technology, and the need by factories to be more efficient and pollute less, Climeworks’s plant will just be a stepping stone. It has proven that carbon can be sucked out of the atmosphere and turned into something useful.

The first step is always the hardest. A solution might just have been found that will dramatically lower carbon emissions and lessen the impact of climate change.