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Climate change and energy

Y Combinator plans to back carbon removal ventures

October 24, 2018

The prominent early-stage investor has invited startups exploring novel ways of sucking greenhouse gases from the atmosphere to apply for its accelerator program.

Background: A growing amount of research concludes it will be nearly impossible for the world to avoid a dangerous 2 ˚C rise in global temperatures merely by cutting greenhouse-gas emissions, given the concentrations already in the atmosphere and the slow pace at which nations are shifting to clean energy. At this stage, the UN’s climate change panel and other institutions have said various methods of capturing and storing carbon dioxide will be required as well.

The problem is that scientists and companies haven’t yet figured out a way to do so economically at anywhere near the scale required.

“It’s time to invest and avidly pursue a new wave of technological solutions to this problem—including those that are risky, unproven, even unlikely to work," Y Combinator said in an announcement on Tuesday. “It’s time to take big swings at this.” 

Four to focus on: Several startups, including Climeworks and Carbon Engineering, have raised money and built facilities to capture carbon dioxide directly from the atmosphere. But Y Combinator highlighted four even earlier-stage approaches to removing greenhouse gases where it would be willing to fund startups, or potentially nonprofit research.

They include using an electrochemical method to accelerate the natural process of mineral weathering, which pulls carbon dioxide out of the atmosphere and oceans; creating genetically engineered phytoplankton that can use photosynthesis to capture and store carbon dioxide in the ocean; artificially flooding deserts to create oases that can support phytoplankton for the same purpose; and engineering enzymes that can efficiently capture and store carbon, and then be disposed of or used to create other products.

The San Francisco accelerator said it would be open to funding other ideas in the space as well. But it's strange that the firm has zeroed in on technologies that are particularly far fetched in a field where even the most advanced ideas, notably direct-air capture or bioenergy with carbon capture and storage, still face enormous economic and technical hurdles.

Risks and rewards: Given the rising risks of climate change, and the muted public policy response so far, it’s crucial to support research into areas that could potentially address the dangers the world faces.

But there’s a separate question of whether such ideas have reached a point yet where it makes sense to create a for-profit venture that could face commercial pressures to deploy solutions before their environmental risks and benefits have been adequately explored. Intertwining profit motives with audacious proposals—like flooding deserts—is also sure to complicate what’s already an incredibly intense public debate over the use of these technologies. 

It's "good to see private capital support high risk but potentially high impact 'outside the box' ideas," said Noah Deich, executive director of Carbon180, an Oakland, California-based group promoting research into carbon recycling, on Twitter. "But the 'move fast and break things' Silicon Valley mindset [is] misaligned with ideas that could have large community and/or ecosystem impacts."

There have been tensions in the past. In 2012, a California entrepreneur involved in carbon offset markets sparked international controversy by dumping iron dust into the Pacific Ocean in an effort to promote plankton growth, in contravention of scientific protocols. 

As a Nature article noted last year, researchers have carried out 13 major studies exploring the use of iron fertilization since 1990, but have struggled to show how much carbon dioxide it actually sequesters. Some scientists do worry, however, that it can adversely impact ocean ecosystems by spawning toxic algal blooms.

Premature interest: Gernot Wagner, executive director of Harvard’s Solar Geoengineering Research Program, said it’s crucial for the private sector to help develop commercially viable ways of removing greenhouse gases. In particular, funding projects enables direct-air capture ventures that are further along technologically “to climb up the learning and slide down the cost curve,” he said in an e-mail.

“That’s where Y Combinator shines,” Wagner added. “For more experimental applications, like cultivating genetically engineered phytoplankton, where the emphasis ought to be on basic research, commercial interest today would be premature.”

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