San Francisco-based climate control company Heirloom Carbon Technologies is building the first direct air commercial carbon capture plant in the United States.
The technology underlying the plant is new, and the huge filters are able to suck as much as 1,000 metric tons of CO2 out of the air annually.
This is a drop in the bucket compared to the billions of tons that scientists believe will need to be captured to help offset global warming.
Microsoft is investing heavily in Heirloom technology by signing a long-term contract to remove 315,000 metric tons of carbon which will help the company become more carbon neutral.
The direct air process uses limestone to trap the CO2 pulled from the air.
Limestone, when heated, releases CO2 which can be captured in containers.
The CO2-depleted limestone is placed on beds in huge stacks and acts like sponges sucking up 50% of their weight in CO2 in a few days.
The limestone is then reheated, releasing more CO2 which is made into concrete which traps it for centuries.
The CO2 strengthens the concrete and limits the need for cement – the ingredient in regular concrete with the worst carbon footprint.
Microsoft has seen its carbon footprint explode in the last year with its investments in building huge AI data centers across the country.
These data centers require huge amounts of electricity and the company continues to seek innovative ways to offset this uptick.
Heirloom estimates that the current cost of the technology ranges from $600 to $1,000 per ton of CO2 removed.
As the company scales, the target is to lower the cost per ton to $100, which will allow the process to be scaled to a large enough degree to make an impact.