The Microsoft cofounder is one of the world’s most prolific philanthropists, and he has said he wants to donate “virtually all” of his $103 billion fortune and drop off the world’s richest persons list. He has called giving a “basic responsibility for anyone with a lot of money” and an interesting challenge, but his latest motivation to donate is a lot more personal.

“I started looking at the world through a new lens recently—when my older daughter gave me the incredible news that I’ll become a grandfather next year,” Gates wrote in his annual year-end letter, published on Tuesday.

Gates’ oldest child, 26-year-old Jennifer, announced her pregnancy last month, and her father described how the experience affected his outlook for the future he wants his grandchildren to have.

“The thought gives a new dimension to my work,” he wrote. “When I think about the world my grandchild will be born into, I’m more inspired than ever to help everyone’s children and grandchildren have a chance to survive and thrive.”

A legacy of giving

Since establishing his first charitable foundation in 1994, Gates and his now ex-wife Melinda French Gates grew their philanthropic careers into the Bill & Melinda Gates Foundation, a household name in the global fight against disease, poverty, and inequality.  

The Bill & Melinda Gates Foundation is the second-largest charitable organization in the world by assets, with an endowment worth nearly $70 billion. Through the foundation, Gates has reportedly donated more than $50 billion since 1994 to eradicate diseases, promote education, and advance gender equality. 

Philanthropy aside, Gates has also invested in early-stage startups that in his view are working on promising solutions to the challenges of today and tomorrow. Through his Breakthrough Energy initiative, which aims to mobilize $15 billion in capital, Gates has funded research on climate solutions and clean energy innovations ranging from studying geoengineering to developing experimental nuclear fusion reactors.

In his recent letter, Gates reiterated his plan to eventually drop off the list of richest people and said he is going “full speed” on his larger project of giving away most of his fortune, but he also warned that global philanthropy is set to face unprecedented challenges in the coming years. Global shocks such as the COVID pandemic and the Ukraine war are “slowing and even reversing” much of the progress made in recent years, Gates wrote, while rising inflation and slowing economic growth is forcing wealthier countries to cut back on foreign aid.

“Through the foundation and my personal work, I am trying to make sure that, even with everything else going on, the world continues to do more to help the poorest,” Gates said. 

Gates also looked ahead to how his philanthropy could benefit younger generations and people of the future. “I also hope that, through my work, I can help make the better world that future generations deserve,” he wrote.

The biggest challenge

The centerpiece of his concern for the next generation, Gates said, is climate change. Warming temperatures have already begun taking a toll on society, and taking action now is critical to protecting our children and grandchildren, according to Gates.

“I can sum up the solution to climate change in two sentences: We need to eliminate global emissions of greenhouse gases by 2050. Extreme weather is already causing more suffering, and if we don’t get to net-zero emissions, our grandchildren will grow up in a world that is dramatically worse off,” Gates wrote in his letter.

While his foundation does work on helping poor communities adapt to climate change, Gates conceded “philanthropy alone can’t eliminate greenhouse gases,” and “markets and governments” are the only real mechanisms to get results on the scale and timeline required.

Despite his commitment to finding solutions, Gates is pessimistic about humanity’s chances of hitting its primary climate goal to keep global temperature rise below 2˚C by the end of the century. “We’re going to have to do mind-blowing work to stay below 2˚C,” he said in an interview with Reuters published on Tuesday, although he was optimistic about the market’s ability to incentivize innovation in the sector.

“It may seem strange to talk about profit-making ventures in a letter about giving away my resources,” Gates wrote in his letter, adding that philanthropy and profit incentives were already collaborating to improve the world’s climate outlook. “The good news is that we’re much further along than I would have predicted a few years ago on getting companies to invest in zero-carbon breakthroughs.”