Family offices back sustainability startups in July

A version of this article first appeared in CNBC’s Inside Wealth newsletter with Robert Frank, a weekly guide to the high-net-worth investor and consumer. Sign up to receive future editions, straight to your inbox.

Investment firms of ultrawealthy families showed no signs of slowing down in July despite a turbulent month for markets between a sharp correction and soaring energy prices.

Last month, family offices made 57 direct investments in companies, holding steady from June, according to data provided exclusively to CNBC by Fintrx, a private wealth intelligence platform.

July’s buzziest deal was a $10 billion fundraise for Jeff Bezos’ Blue Origin, which included $2 billion from the Amazon billionaire’s namesake family office. Bezos Expeditions is the most active family office investor thus far this year, backing five artificial intelligence startups in June alone.

While AI startups represented the bulk of the month’s dealmaking activity, more than 15% of investments were made in clean energy and sustainability firms. Antora Energy, a thermal battery startup, closed a $550 million Series C round that included venture capital billionaire John Doerr as an investor. Foris Ventures, Doerr’s private venture firm, has backed other clean energy firms like Panthalassa, Pacific Fusion and Rondo Energy.

Investors’ appetite for renewable energy has cooled in recent years due to backlash against environmental, social and governance, or ESG, strategies, as well as the Trump administration’s crackdown on climate initiatives and policy. However, the power demands of AI and the fuel crisis caused by the Iran war have rejuvenated interest in green energy.

U.S. sustainability funds reported inflows of $3 billion in the second quarter of 2026, ending a streak of 14 quarters of net outflows, according to Morningstar.

“Roaring demand for electricity, shifting geopolitics, and disruptive market forces are reshaping the world as we know it. The question is: How will we respond?” Doerr wrote in April, announcing a new action plan for solving the climate crisis. “What was once an opportunity is now an imperative. Only clean energy can meet the surging demand for affordable, durable, and sustainable energy. Only clean energy can deliver abundance that lasts.”

Legendary energy trader John Arnold backed Hephae Energy Technology, an advanced geothermal drilling startup, in a $17.8 million Series A round that closed in July.

“I’m very interested in the geothermal story, the advanced geothermal story, which can unlock a lot more of that resource and provide the baseload power in many locations at what appears to be kind of a market price,” Arnold told CNBC’s Melissa Lee in February.

Family offices’ interest in renewable energy and sustainability has largely endured even as many traditional investors have retreated. More than half of respondents in a September poll of 346 family offices conducted by Citi Private Bank said they were likely to allocate to sustainable investments in the next five years.

This support is likely to continue as the next generation takes the reins, per a Bank of America survey released in November. More than half of family office principals said they expected heirs to maintain or increase their firms’ allocation to sustainable or impact investments.

Walmart heir Lukas Walton has dedicated his family office, Builders Vision, to advancing environmentalist and sustainability efforts through investing and philanthropy. In July, Builders Vision joined a $43 million Series A for Lydian, which produces synthetic aviation fuel, alongside Grok Ventures, the private investment firm of Atlassian’s billionaire CEO Mike Cannon-Brookes.