Major tech companies, including Google, Salesforce, and H&M, have signed multimillion-dollar deals to capture carbon dioxide emissions from wastewater treatment plants and paper mills. The agreements, facilitated by the carbon removal initiative Frontier, aim to take CO2 out of the atmosphere and help companies meet their sustainability goals.

The $80 million investment will be split between two startups: CREW, which will capture carbon dioxide emissions produced at wastewater treatment facilities, and CO280, which will retrofit pulp and paper mills with carbon capture technologies. CREW's strategy involves adding alkaline minerals to water treatment tanks to trap CO2 produced by microbes, while CO280 uses devices initially developed by the fossil fuel industry to capture CO2 emissions from smokestacks.

The move marks a shift in companies' approaches to mitigating climate change. Instead of solely relying on industrial plants that filter CO2 out of the ambient air or seawater, they are now exploring novel tactics for drawing down carbon dioxide. According to Wil Burns, co-director of the Institute for Responsible Carbon Removal at American University, "We do need to be looking at a lot of different kinds of approaches... Some of these approaches still remain extremely expensive, notably direct air capture, so we're looking for approaches that potentially are less expensive."

The cost of carbon capture technology remains a significant hurdle. The first generation of industrial facilities built over the past decade or so to filter CO2 out of the air cost companies upwards of $600 per ton of captured carbon. The deals brokered by Frontier come out to around $447 per ton of CO2 removal by CREW and $214 per ton for CO280's services. While this is a significant reduction, it is still well above the $100 per ton that industry leaders often say they're targeting.

Carbon dioxide removal encompasses a suite of strategies to take carbon dioxide out of the atmosphere. These technologies could potentially help slow climate change by trapping some of the pollution fossil fuels have already released over the years. However, experts caution that carbon removal is no substitute for preventing greenhouse gas emissions in the first place. Companies buying carbon removal services also face criticism from environmentalists who argue that it's a distraction from more critical efforts to transition from fossil fuels to clean energy.

Despite these concerns, the investment in CREW and CO280 marks a significant step towards exploring alternative approaches to carbon capture. As companies like Google, which was responsible for 14.3 million metric tons of carbon dioxide pollution last year, continue to grapple with the challenges of reducing their carbon footprint, innovative solutions like these may play an increasingly important role in the fight against climate change.

While the effectiveness of carbon capture technologies as a way to mitigate climate change remains uncertain, the willingness of major tech companies to invest in novel approaches is a promising sign. As the world continues to grapple with the complexities of climate change, it is clear that a multifaceted approach will be necessary to address this critical issue.