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We asked Bill Gates, a Nobel laureate, and others to name the most effective way to combat climate change

Their answers included rising carbon prices, storage breakthroughs, a fusion moonshot and more.

off shore drilling
An off-shore drilling platformGetty
February 24, 2021

Despite decades of warnings and increasingly devastating disasters, we’ve still made little progress in slowing climate change.

Clean energy alternatives have secured just a fraction of the marketplace today, with renewables generating around 10% of global electricity and electric vehicles accounting for about 3% of new sales. Meanwhile, greenhouse-gas emissions have continued to climb year after year, aside from the occasional recession or pandemic.

Given the lack of momentum, how do we make faster, more significant progress? We asked 10 experts across a variety of disciplines, including climate scientists, economists, physicists, and policy experts, a single question: 

“If you could invent, invest in, or implement one thing that you believe would do the most to reduce the risks of climate change, what would it be and why?”

Here’s what they had to say.

Bill Gates

Bill Gates

Cofounder of Microsoft and
chairman of Breakthrough Energy (US)

Right now, I’m investing a lot in nuclear fission. Our company [TerraPower] … just got a huge US government contract to develop that reactor, which we call Natrium. 

A lot of people would say a storage miracle and some people would say super-cheap, clean hydrogen. The nice thing about super-cheap, clean hydrogen—forget about whether it ever competes in passenger cars; it probably doesn’t—is it potentially solves a lot of problems.

It requires the cheapest electricity in the world and the cheapest capital cost in the world, if you’re going to do it through electrolyzers cracking water. 

That could work—we should try—but we can’t count on it. You can’t just focus on one thing, because you may hit a dead end, just like we may not get fusion or [next-generation] fission or the storage miracle. 

Sally Benson

Sally Benson

Director of the Global
Climate & Energy Project,
Stanford University (US)

Wise, inclusive, courageous, and decisive leadership. 

Wise because the stakes are so high and solving the climate problem is so complex. Inclusive because we need everyone working to solve the climate problem. Courageous because many tough decisions need to be made, and most of them are sure to make some people unhappy. Decisive because we don’t have a moment to waste.

Elizabeth Kolbert

Elizabeth Kolbert

Staff writer at the New Yorker and author of Under a White Sky: The Nature of the Future (US)

I would impose an economy-wide carbon tax that would increase year by year. I’d use some of the proceeds to offset the regressive impact of the tax on low-income families and the rest to invest in low-carbon infrastructure. 

Although I don’t believe in putting too much faith in economic models, I have to believe economists are correct in saying this would be the most efficient way to bring carbon emissions down. And we just don’t have time for inefficiency at this point. 

John Dabiri

John Dabiri

Professor of aeronautics and mechanical engineering, California Institute of Technology (US) 

I would invest in a moonshot and a hedge. 

The moonshot would be modular nuclear fusion. It would provide on-­demand power with unlimited fuel, no long-lived waste, and limited risk of weapons proliferation. If achieved in a sufficiently small footprint, it could be accessible to developing countries, where energy demand will increase most significantly. 

No other carbon-free energy source checks all these boxes. 

As a hedge, I would leverage our immense and ever increasing computational powers to develop a high-­resolution Earth model that can predict extreme weather events weeks in advance. Some of the most acute climate risksflooding and fires, for exampleare especially dangerous because they’re currently unpredictable. If we can extend weather prediction even further, from weeks to months in advance, perhaps even seasonal droughts could become a nuisance rather than an existential threat.

Adam Marblestone

Adam Marblestone

Innovation fellow,
Schmidt Futures (US)

Fortunately, it turns out that if you drill deep enough into hot enough rock, you can access clean, safe baseload and dispatchable geothermal energy almost anywherein principle. A large-scale expansion of geothermal energy availability would fill a key gap due to the intermittency of renewables, notwithstanding a hoped-for gigantic rollout of next-generation storage and transmission technologies. 

While geothermal needn’t supersede other options in the long-term pipeline for baseload and dispatchable energylike novel compact fusion approaches leveraging high-temperature superconductors, or small modular fission reactorsit has the advantage of using more pedestrian technology and building on existing oil and gas talent and supply chains. 

Rhianna Gunn-Wright

Rhiana Gunn-Wright

Director of climate policy, Roosevelt Institute,
and one of the architects of the Green New Deal (US)

Let’s be clear: the covid-19 recession and climate change are not happening in isolation from one another. Our government is trying to rebuild our economy at the same time—and in the same places—as fires rage, waters rise, and homes are destroyed. To underestimate the depth of this recession and the impending threat of climate disaster would be a costly mistake—and, unfortunately, one that we have made before.  

That is why if I could implement one thing to reduce the risks of climate change, I would ensure that stimulus policies designed to respond to the current economic crisis are also designed to create sustainable, long-term growth. To get these kinds of green stimulus policies off the ground fast, we can use existing programs meant to alleviate energy poverty and aging infrastructure and provide relief funding to encourage a permanent transition to a low-carbon economy. 

 I would also redirect resources toward rapidly scaling up production of key goods and services, and transitioning workers into different sectors crucial to decarbonization.

Steven Chu

Steven Chu

Former US energy secretary
and professor of physics,
Stanford University (US)

At the top of my list would be low-cost, long-duration energy storage. 

Most lithium-ion battery systems being installed today are used to improve the stability of the power system, storing a few hours of energy each day during periods of peak electricity generation and releasing it during the peak demand. For example, the peak of solar generation is at noon but the peak demand for electricity occurs at roughly 4 p.m. For renewable sources to provide 80% of the electricity on the grid, given the huge seasonal dips in solar and wind output, we’ll need technologies capable of storing as much as 100 hours of energy, a recent Joule study estimated.

Storage also needs to get much cheaper. Ultimately, the US will need to build enough storage of all types to provide 10,000 gigawatts of backup electricity, up from only around 25 gigawatts today.

Ken Caldiera

Ken Caldeira

Senior advisor on climate science, Gates Ventures, and senior staff scientist emeritus, Carnegie Global Ecology (US)

If I could only implement one thing to reduce the risks of climate change, it would be a simple, non-gameable fee for extracting fossil fuels from the ground, which would increase by a fixed percentage each year. This would send a clear signal to the markets that every technology emitting carbon dioxide from fossil fuels will eventually become more expensive than any alternative.

Accurately measuring the carbon removed is relatively easy to do and not easy to game, unlike with the increasingly popular carbon offset programs that climate polluters are relying upon to balance out their emissions by paying for tree planting and similar efforts.

Nadia Ouedraogo

Nadia S. Ouedraogo

Economic affairs officer,
United Nations Economic Commission for Africa (Ethiopia)

The Paris agreement calls for keeping the global temperature rise to no more than 1.5 ˚C above preindustrial levels. Renewables alone won’t get us there. Around 44% of the emission reductions needed to meet the Paris [threshold] will come from energy efficiency, with another 36% from switching to renewables. By implementing energy-efficient measures and nothing else, we could lower greenhouse-gas emissions 12% by 2040. The right efficiency policies could enable the world to achieve a significant portion of the emissions cuts needed to reach its climate goals without any new technology.

Navroz Dubash

Navroz Dubash

Professor at the Centre
for Policy Research (India)

There is a lot of talk about the fact that country pledges don’t add up to emissions reductions required by science. We should be talking as much, or more, about the absence of governance mechanisms that translate visions into policies. Durable national institutions are a missing piece in our collective response to climate mitigation and adaptation. They are needed to lay out a strategic vision and set targets, coordinate implementation across sectors, and mediate politics. But approaches to climate governance have to suit national context; when countries get ahead of their climate politics, the policies, goals, or systems that result can become unstable or unachievable.

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