What if we could suck CO2 out of air and pack it away

NEW DELHI: Is combating global warming as simple as collecting the carbon dioxide (CO2) in the air and burying it forever? A European company thinks that it is just the strategy that would work against climate change. With global average atmospheric CO2 levels today higher than at any point in the past 800,000 years, here’s why the idea could be useful, especially when the Intergovernmental Panel on Climate Change has said that we may need to extract CO2 from the air to effectively counter global warming.





SELLING CO2 BY THE TONNE

Climeworks, a company based in Switzerland has developed what are called “direct air capture” machines that can draw in CO2 from the air. Its rooftop plant outside Zurich is the first direct-air-capture venture in history seeking to sell CO2 by the tonne.

HOW THIS TECHNOLOGY WORKS

The system for CO2 capture involves a machine that uses electric fans to pull air into ducts and over a special material, known as a sorbent.

Once the filter is saturated with CO2 the filter is heated to 1000 C.

WHAT IS DONE WITH THE CAPTURED CO2?

➤ Climeworks sells the extracted CO2 for use in carbonated drinks, and in agriculture.
➤ It can also be combined with hydrogen to produce different kinds of fossil-fuel substitutes.
➤ But Climeworks aims to capture CO2 and bury it deep underground, as it has already done in Iceland. It intends to sell this service as an offset.
➤ For the more environmentally conscious, the firm says it can develop an app that shows users how much CO2 a particular activity released into the atmosphere and offer to remove that from the air for a fee.

THE TECH'S NOT CHEAP, BUT COULD GET THERE

Climeworks’s founders believe they can greatly bring down the cost of capturing CO2 so that their machines are seen as a viable solution. At present, it costs the firm $500-$600 to remove a tonne of CO2 from the air. But it wants to bring that down to about $100 per tonne.

THEY’RE COUNTING ON ADVANCES IN TECH

When solar and wind power first came, their costs were much higher than fossil fuel. But now more than 20% of world’s annual electricity supply comes from renewables. Climeworks’s founders say they want to achieve an assembly line scale with their air capture equipment so that it can be mass produced like cars.

CAN IT EVEN MAKE A DENT AGAINST COLOSSAL EMISSIONS?

A whopping 37 bn tonnes of CO2 are emitted annually. To meet Paris Accord’s goal of limiting global temperature rise, CO2 emissions need to be brought down to 15-20 bn tonnes annually by 2030 and to zero by around 2050. Climeworks wants to capture 1% share of annual CO2 emissions by mid 2020s . To do that it would need 250,000 carbon-capture plants like the one it now operates, or about 4.5m carbon collector machines. It presently runs just 18 such machines at its Swiss plant and captures 1,000 tonnes of CO2.