It Could Have Been So Much Worse for Climate Tech

When I reached out to climate tech investors on Tuesday to gauge their reaction to the Senate’s proposed overhaul of the clean energy tax credits, I thought I might get a standard dose of can-do investor optimism. Though the proposal from the Senate Finance committee would cut tax credits for wind and solar, it would preserve them for other sources of clean energy, such as geothermal, nuclear, and batteries — areas of significant focus and investment for many climate-focused venture firms.

But the vibe ended up being fairly divided. While many investors expressed cautious optimism about what this latest text could mean for their particular portfolio companies, others worried that by slashing incentives for solar and wind, the bill’s implications for the energy transition at large would be categorically terrible.

“We have investments in nuclear, we have investments in geothermal, we have investments in carbon capture. All of that stuff is probably going to get a boost from this, because so much money is going to be flowing out of quote, unquote, ‘slightly more established’ zero emissions technologies,” Susan Su, a climate tech investor at Toba Capital, told me. “So we’re diversified. But for me, as a human being, and as somebody that cares about climate change and cares about having an abundant energy future, this is very short-sighted.”

Bigger picture aside, the idea that the Senate proposal could lead to more capital for non-solar, non-wind clean energy technologies was shared by other investors, many of whom responded with tentative hope when I asked for their thoughts on the bill.

“The extension of the nuclear and geothermal tax credits compared to the House bill is really important,” Rachel Slaybaugh, a climate tech investor at DCVC, told me. The venture firm has invested in the nuclear fission company Radiant Nuclear, the fusion company Zap Energy, and the geothermal startup Fervo Energy. As for how Slaybaugh has been feeling since the bill’s passage as well as the general sentiment among DCVC’s portfolio companies, she told me that “it's mostly been the relief of like, thank you for at least supporting clean, firm and bringing transferability back.”

Indeed, the proposed bill not only fully preserves tax credits for most forms of zero-emissions power until 2034, but also keeps tax credit transferability on the books. This financing mechanism is essential for renewable energy developers who cannot fully utilize the tax credits themselves, as it allows them to sell credits to other companies for cash. All of this puts nascent clean, firm technologies on far more stable footing than after the House’s version of the bill was released last month.

Carmichael Roberts of Breakthrough Energy Ventures echoed these sentiments via email when he told me, “the Senate proposal is a meaningful improvement over the House version for clean energy companies. It creates more predictability and a clearer runway for emerging technologies that are not yet fully commercial.” Breakthrough invests in multiple fusion, geothermal, and long-duration energy storage startups.

Amy Duffuor, co-founder and general partner at Azolla Ventures, also acknowledged in an email that it’s “encouraging” that the Senate has “seen the way forward on clean firm baseload power.” However, she issued a warning that the unsettled policy environment is leading to “material risks and uncertainties for start-ups reliant on current tax incentives.”

Solar and wind are by far the most widely deployed and cost-competitive forms of renewable energy. So while they now mainly exist outside the remit of venture firms, there are numerous climate-focused startups that operate downstream of this tech. Think about all the software companies working to optimize load forecasting, implement demand response programs, facilitate power purchase agreements, monitor grid assets, and so much more. By proxy, these startups are now threatened by the Senate’s proposal to phase out the investment and production tax credits for solar and wind projects beginning next year, with a full termination after 2027.

“I think solar and wind will survive. But it's going to be like 80% of the deals don't pencil for a long time,” Ryan Guay, co-founder and president of the software startup Euclid Power, told me. Euclid makes data management and workflow tools for renewable project developers, so if the tax credits for solar and wind go kaput, that will mean less business for them. In the meantime though, Guay expects to be especially busy as developers rush to build projects before their tax credit eligibility expires.

As Guay explained to me, it’s not just the rescission of tax credits that he believes will kill such a large percent of solar and wind projects. It’s the combined impact of those cuts, the bill’s foreign entity of concern rules restricting materials from China, and Trump’s tariffs on Chinese-made components. “You’re not giving the industry enough time to actually build that robust domestic supply chain, which I agree needs to happen,” Guay told me. “I’m all for the security of the grid, but our supply chains are already very constrained.”

Many investors also expressed frustration and confusion over why Senate Republicans, and the Trump administration at large, would target incentives for solar and wind — the fastest growing domestic energy sources — while touting an agenda of energy dominance and American leadership. Some even used the president’s own language around energy issues to deride the One Big Beautiful Bill’s treatment of solar and wind as well as its repeal of the electric vehicle tax credits.

“The rollbacks of the IRA weaken the U.S. in key areas like energy dominance and the auto industry, which is rapidly becoming synonymous with the EV industry,” Matt Eggers, a managing director at the climate-tech investment firm Prelude Ventures, wrote to me in an email. “This bill will still ultimately cost us economic growth, jobs, and strategic positioning on the world stage.”

“The only real question is, are we going to double down on the future and on American dynamism?” Andrew Beebe, managing director at Obvious Ventures, asked in an emailed response. “Or are we going to cling to the past by trying to hold back a future of abundant, clean, and affordable energy?”

Su wanted to focus on the bigger picture too. While the Senate’s proposal gives tax credits for solar and wind a much longer phaseout period than the House’s bill — which would have required projects to start construction within 60 days of the bill’s passage and enter service by 2028 — Su still doesn’t think the Senate’s version is much to celebrate.

“The specific changes that came through in the Senate version are really kind of nibbling at the edges and at the end of the day, this is a huge blow for our emissions trajectory,” Su told me. She’s always been a big believer that there’s still a significant amount of cutting edge innovation in the solar and wind sectors, she told me. For example, Toba is an investor in Swift Solar, a startup developing high-efficiency perovskite solar cells. Nixing tax credits that benefit the solar industry will hit these smaller players especially hard, she told me.

With the Senate now working to finalize the bill, investors agreed that the current proposal is certainly not the worst case scenario. But many did say it was worse than they had — perhaps overly optimistically — been holding out for.

“To me, it's really bad because it now has a major Senate stamp of approval,” Su told me. The Senate usually tempers the more extreme, partisan impulses of the House. Thus, the closer a bill gets to clearing the Senate, the closer it usually is to its final form. Now, it seems, the reconciliation bill is suddenly feeling very real for people.

“At least back between May 22 and [Monday], we didn't know what was going to get amended, so there was still this window of hope that things could change more dramatically." Su said. Now that window is slowly closing, and the picture of what incentives will — and won’t — survive is coming into greater focus.