When I was 28 years old, two friends and I got the invitation of a lifetime. MacArthur Foundation, The Rockefeller Foundation, and The Pew Charitable Trusts wanted a new joint initiative on the environment. Improbably, they asked three recent Stanford University graduates—Hal Harvey, Tom Strand, and me—to design an initiative to solve the nexus of problems around energy. In 1991, the Energy Foundation was born.

We can safely say our founders’ big bet has paid off by advancing the vision, the policy, and huge new markets to create a prosperous clean energy economy. And their original idea, that philanthropy could make a difference in solving the world’s energy challenges, spread from the U.S. to China, and beyond.

With great pride, and no small amount of sadness, it is time for me to move on to something new.

I’m proud—and sometimes in awe—of the gains we all have made since 1991. Our starting vision was laughable to top energy experts 28 years ago: affordable, clean, low-carbon energy for everyone.

Today we can celebrate major steps forward across a number of sectors:

• Renewables are now the cheapest energy-generating source on the planet.
• China is the largest market and manufacturer for wind and solar.
• The global clean energy industry is approaching $400 billion per year in investment.
• California—the globe’s sixth largest economy—is on track for a 100 percent clean energy electric grid by 2045.
• Automated and electric vehicles will make it cleaner, easier, and cheaper to get around—without owning your own car.
• As battery prices continue to fall, commercial trucks will electrify, disrupting the entire goods movement system.
• Nine newly elected governors committed to either 50 percent or 100 percent renewable energy goals, and three Republican governors also ran—and won—with clean energy platforms.

Combined, all of these steps will bring cleaner air to tens of millions of people and, with a low-carbon grid, significantly reduce carbon emissions long-term.

We have come a long way together. We’ve shown, without a doubt, that a strategic intermediary, operating at scale and partnering with leading foundations and donors around the world, can accelerate change. Yet none of this matters until enough tons of carbon or methane are reduced, until enough coal plants are retired, until enough new wind turbines spin, or until voters, old and new, elect clean energy champions to leadership positions. We still have a long way to go and we have to move fast.

We can solve this. I’m confident I leave the Energy Foundation well-positioned to continue this fight, with strong governance and deep leadership.

It has been an honor and a challenge to build this organization in partnership with so many talented people, from the network of hundreds of grantees, to our funding partners, to our board, and to our staffs in the U.S. and China. Thank you. And special thanks to the Packard and Hewlett foundations, who had the vision in 1999 that our success in the U.S. could be adapted to China, and so launched Energy Foundation China.

And I will be continuing the fight from my new firm, called Tapeats Partners LLC. It’s named after Tapeats Sandstone, which rises from the earth at mile 58 on the Colorado River in the Grand Canyon. This is a spot that fills me with awe and inspires me to protect this beautiful planet and create a clean and prosperous future for generations ahead.

I’m not saying goodbye; instead, I’ll close with what I often said at the Energy Foundation: “Full speed ahead.”  I look forward to continuing our fight together.