Silicon Valley's largest accelerator is looking for technology that can remove excess carbon dioxide from the air

• Most scientists agree that we need to suck up carbon dioxide from the atmosphere to avoid the worst consequences of climate change.

• Y Combinator, Silicon Valley's largest startup accelerator, this week launched a request to start-ups working on high-tech ways to remove CO2 from the air.

• A recent report from the National Academies of Science, Engineering and Medicine suggests that the US government should also immediately invest in "negative emissions technologies".

For decades, scientists have explained to us that it's pretty simple to avoid a dark future characterized by heat waves, intensely strong storms and extensive coastal flooding: stop injecting as many gas trapping heat in the atmosphere.

This could be achieved by improving the energy efficiency of our cars, buildings and factories and replacing fossil fuels with renewable energy sources such as wind and solar.

Not anymore. We have waited too long and now it is too late: we throw so much gas into the heat that holds heat in the atmosphere that emission reductions will not be enough. To prevent the Earth's temperature from rising beyond the threshold that scientists consider safe (something we're about to do, in the next 20 years), it's now necessary to vent some of the dioxide carbon we rejected.

This is the conclusion of a recent landmark report by the Intergovernmental Panel on Climate Change (IPCC), a group of thousands of scientists from around the world. And that means that whoever finds out how to purify CO2 quickly and cheaply can make a lot of money.

This reality has attracted the attention of Silicon Valley's largest startup accelerator.

Earlier this week, Y Combinator, which has been supporting companies such as Airbnb and Reddit, has launched a request to start-ups working on a technology capable of removing carbon dioxide from the atmosphere.

"It is time to invest and passionately seek out a new wave of technological solutions to this problem, including those that present risks, have not yet been proven, and are unlikely to succeed. to work, "says Y Combinator's website.

Y Combinator is looking for startups working on four approaches recognized as "straddling the border between very difficult to science fiction" – the genetically engineered phytoplankton to turn CO2 into a form of carbon ready for storage, thus accelerating a natural process in which the rocks react CO2 creates cell-free enzymes that can process carbon and flood the deserts of the Earth to create oases.

Sam Altman, president of Y Combinator, acknowledged that these ideas were "gunfire", but said he wanted to take a broader approach to the problem.

A plan to build the "largest infrastructure project ever undertaken"

The demands of Y Combinator are much more futuristic and unrealized than the current methods of capturing carbon in the air.

Perhaps the most realistic idea of ​​his four technological ideas is what the accelerator calls "electro-geochemistry". The idea is that engineers accelerate the rate at which certain types of rocks bind and react naturally with CO2. (The approach is also sometimes called mineralization of carbon or mineral alteration.)

Another idea is to modify the genes of microscopic marine plants, called phytoplankton, so that they can convert CO2 into a stable and sequestered form of carbon through photosynthesis. These CO2-capturing organisms could then spread to the oceans (assuming the conditions are favorable enough for their survival) and the by-product they manufacture would sink to the bottom of the ocean.

A third idea involves enzymes: tiny proteins in cells that act as catalysts, accelerating the chemical reactions that convert one type of molecule into another. Some enzymes can, for example, take carbon dioxide and turn it into other useful organic compounds. The idea of ​​Y Combinator is to create enzymatic systems that can convert carbon into useful byproducts without having to be in the cells of a living organism.

Finally, Y Combinator uses startups that could create millions of small oases in the deserts of the Earth, an area of ​​about 1 square kilometer. These waters could harbor phytoplankton sucking CO2. The oases would also serve as fresh water for nearby humans and habitats for plants and trees that can absorb CO2.

"Creating 4.5 million one-square-kilometer oases would allow us to sequester more than current global emissions (more than 41 gigatonnes of CO2 per year), while requiring only the equivalent of half the world's surface area. Sahara Desert, "says Y Combinator's request. (Half of the Saharan territory is about 1.7 million square miles.)

But he also acknowledges that "it would be the largest infrastructure project ever undertaken."

All these concepts are still just that: hypothetical ideas. None have been rigorously tested outside a laboratory and few (if any) companies work there publicly.

"These ideas go beyond what is possible, and we do not know which side of the line they are on," says Y Combinator's request.

Embrace negative emissions technologies

But Y Combinator could be on something. The National Academies of Science, Engineering and Medicine (NAS) released a report this week on "Negative Emissions Technologies". The authors found that simple and existing carbon removal strategies (such as reforestation of cleared land) could never capture enough. carbon to prevent the temperature of the Earth from rising.

In the past, some environmentalists have been reluctant to fully support advanced carbon capture technologies because they are expensive solutions that do not yet exist at the scale needed to make a difference. In addition, some critics have suggested that negative-release technologies could serve as a justification for continuing to emit the greenhouse gases that put us in this situation in the first place.

But given the recent IPCC assessment, it has become clear that emission reductions and carbon reduction technologies are now essential. And that need spurred the tech sector, as few green technology opportunities had before, according to Kate Gordon, a member of Columbia's Center on Global Energy Policy.

"The tech community is really excited about this space, especially the cool way people use carbon to turn it into products," Gordon told Business Insider. "We have not seen this kind of interest for a long time in the technology sector, except for electric vehicles. [electric vehicles], I would say. It's a bit like that kind of commitment.

But the government's investment remains crucial

Many private companies are already working on carbon capture technology, but none of the approaches proposed by Y Combinator. In Switzerland, Climeworks has developed a technology that sucks air into a plant and then captures CO2 via a filter. And in Canada, Carbon Engineering has a facility that captures carbon dioxide from the air; the company is also focusing on recycling this CO2 into liquid transport fuel.

But the NAS report says that in order to develop sufficiently fast and cost-effective negative-emission technologies, the US federal government must immediately invest.

"When you see commercial clean energy technologies deployed pretty widely, like solar and wind, the government has been part of it since the beginning [research and development] Erin Burns, a senior policy advisor for Third Way Think Tank, told Business Insider. "I do not think it's different for a technology like direct capture in the air."

"The private sector is looking for some signals from the federal government, and I think it has a very important role to play," Burns said.

According to the NAS report, beyond stabilizing the climate and preventing future disasters, investing in these technologies would help the United States economically, as carbon capture will require even more. The first countries and companies to have developed scalable and cost-effective carbon reduction technology will benefit as demand for this intellectual property increases.

"That's where markets go. That's the new set of technologies that people are starting to pay attention to, "Gordon said. "Otherwise, we will buy it from someone else because someone will do it."

This is probably part of Y Combinator's motivation to ask startups who are working on these ideas. The accelerator said it was also open to funding non-profit research as part of its approach.

"This is a big, ambitious issue and we look forward to meeting the founders, scientists, philanthropists, and many others who do it first," says Y Combinator's request.

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