REUTERS / Lindsey Wasson

Jeff Bezos, the chief executive of Amazon and the world’s richest man, announced yesterday that he would give $10 billion to fight climate change.

He didn’t say much else. It’s not clear where the money will go, or how fast Bezos will spend it. He didn’t lay out a theory of change. In a 127-word Instagram post that doubled as a press release, he said only that a new entity, the Bezos Earth Fund, would support “scientists, activists, [and] NGOs—any effort that offers a real possibility to help preserve and protect the natural world.”

This gift is undeniably important. It could, by some estimates, virtually double the amount spent on climate change by American philanthropists today. And it will likely reveal something counterintuitive about the state of global climate action. Even if you believe, as Bezos does, that climate change is “the greatest threat facing our planet,” spending $10 billion to fight it is still pretty difficult.

Why? The first issue is organizational. “Dropping a big, fat check into the water is not necessarily going to make the sharks all swim in the same direction. It’s going to be either a feeding frenzy or a total mess until things get sorted out, and unfortunately we don’t have time to waste,” Daniel Firger, the managing director of Great Circle Capital Advisors, a climate-finance consulting firm, told me. (Until last year, Firger worked for the climate philanthropy of Michael Bloomberg, the Democratic presidential candidate and former New York City mayor.)

But the deeper challenge has to do with scale and imagination. There are only so many nonprofits and experts working on climate change. If a successful group has an annual budget of $10 million, then giving it $50 million will not necessarily make it five times as effective. Many helpful projects are probably too small for Bezos. “Across the entire landscape, there are not enough people and projects that can take the kind of capital we need,” Firger said.

Bezos has pledged a titanic amount of money. If he spends it evenly across 10 years, he would immediately be the country’s biggest climate philanthropist. The Hewlett Foundation, which holds that title today, spends $120 million per year on climate projects. At roughly $1 billion a year, Bezos would more than octuple that amount. It is a testament to Bezos’s wealth that he could single-handedly devote $400 million a year to new-energy R&D, exceeding what the federal government spends on ARPA-E, the Department of Energy’s advanced-research incubator—and still have $600 million a year left over for everything else.

At the same time, $10 billion is not nearly enough to save the world. Consider the Gateway Tunnel, one of America’s largest pending public-works projects. When completed, the 11-mile tunnel will double the number of trains that can pass between New York and New Jersey at rush hour. If the United States hopes to flush carbon pollution out of its economy, it will have to complete many projects at the Gateway Tunnel’s size and scale. But the tunnel is projected to cost about $9.5 billion, or roughly $860 million per mile. Bezos’s magnanimous gift of $10 billion can buy one Gateway Tunnel.

Of course, this is a slightly facetious comparison—it’s not like Bezos was planning to invest in tristate-area infrastructure. But any similar build-out would present challenges. Jenny Chase, a solar-energy analyst for BloombergNEF, told me in an email that $10 billion would not do much good supporting large-scale solar projects: There is already a surfeit of capital chasing them.

Where could $10 billion go the furthest? It just may be politics. In 2016, the network of conservative groups run by the industrialists Charles and David Koch promised to spend about $900 million on the presidential election. Two years later, it pledged about $400 million to the 2018 congressional midterms. Both of those amounts, widely covered as unprecedented interventions in the political system, represented not only the personal donations of the Kochs but the pooled contributions of hundreds of like-minded donors.

But with his $10 billion, Bezos could single-handedly spend comparable amounts on every presidential and midterm election from now to 2050—supporting climate-friendly members of Congress, governors, and presidents. Once in office, those politicians could then shake loose far more than $10 billion for tunnels, new rail projects, and everything else.

And unlike other donors, Bezos—an accomplished blogger—is free to spend generously in politics. Because he pledged the $10 billion as a personal commitment, and not as an outlay from a preexisting foundation, Bezos is legally allowed to give it to political causes, as well as to candidates, parties, and super PACs. Wealthy foundations with dead benefactors cannot participate in the political system to the same degree.

Of course, politics isn’t the only place he could spend. He could also endow prizes for people who build certain climate-friendly moonshot technologies, such as electric planes or cheaper batteries. Jenny Chase, the solar analyst, suggested in her email that Bezos build out zero-carbon power infrastructure in countries that would otherwise turn to fossil fuels: Perhaps he could add solar panels to every school roof in Indonesia, she mused. The climate scientist and policy guru Joseph Majkut dreamed on Twitter that Bezos could decarbonize a single U.S. state to demonstrate that it can be done: “Pour [money] into the state university, vocational schooling, community grants. Grease every wheel. All the human capital you buil[d] will diffuse to other jurisdictions,” he said.

Bezos isn’t the only newcomer to the climate fight. In the past six months, investment banks and private-equity firms have pledged hundreds of billions of dollars to climate solutions. (Goldman Sachs committed $750 billion late last year.) What those bankers  are discovering is that there are not enough projects to sop up the deluge. “I think it’s as much a failure of imagination as much as it’s a failure of the market,” Firger said.

The success of those investments may turn on the same question as Bezos’s gift: Will climate solutions, long a tiny sector of the economy, scale up quickly enough to (1) guzzle the new flood of cash and (2) prevent the unthinkable? It’s going to be one of the most fascinating stories of the coming year—and one of the most important of the coming century.

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