US early-stage energy investment is not short of money. It is short of proof.

US energy capital is concentrating into fewer, larger and more conditional investments. Fervo Energy’s Project Red shows why: operational proof can allow a company to combine equity, debt and grants rather than treating every need as an equity round. For founders, the task is to identify the one risk that is blocking the next capital provider, then fund the evidence needed to remove it. For investors, the question is whether the company can reach that next milestone within the time and return expectations of the capital already on its books.

Fervo Energy did not begin with a fully proven geothermal power business.

The Houston-based enhanced geothermal systems developer had to show that its technology could produce dependable power in the real world. In 2023, its Project Red pilot delivered 3 MW of baseload generation, with a stable flow rate of about 60 litres per second. Baseload means steady power, rather than output that comes and goes with conditions.

Only then does the funding number make sense. Fervo has been backed by more than $1.5 billion in equity, debt and grants, according to its public company profile. The point is not that every energy startup can raise a very large sum. Quite the opposite. Project Red supplied a piece of evidence that let different kinds of money see a different kind of risk.

Fervo Energy shows how operating evidence can support a combination of equity, debt and grants. Photo: Braddah n8 / Wikimedia Commons, CC0.

That is the answer founders often do not want to hear: early-stage energy investment in the US is not dead. It has become conditional.

A business can have an exciting technology, a vast market and a persuasive slide deck, yet still be unfinanceable today. Not because nobody believes in clean energy. Because the money it is asking for cannot afford to wait through the particular uncertainty still sitting in front of it.

GI Network's view: Energy financeability is a relay race. Each investor needs enough proof to hand the business safely to the next source of capital. A round that reaches no handover point is not runway. It is delay.

The funding gap that is not really a funding gap

At first glance, the numbers look bleak. Global future-energy venture capital fell 16% to $24.5 billion in 2025, while the number of funding rounds fell 24%, according to Oliver Wyman.

Then look again. The average round rose from $17 million to $19 million. And average early-stage low-carbon energy deals rose from $21.7 million in the first quarter of 2025 to $47.6 million in the second quarter of 2026.

Money did not disappear. It gathered around fewer companies.

That distinction matters. A founder looking only at the headline decline concludes that investors have abandoned the sector. A founder looking at the deal pattern asks a harder and more useful question: what did the companies receiving those larger cheques make believable?

The answers recur across the evidence. They addressed near-term electricity demand, grid pressure, reliability, technical performance or a credible route through project development. Oliver Wyman identified energy services, battery and storage, and nuclear technology as the largest categories. Rising electricity demand linked to AI and data centres has sharpened investor interest in energy solutions that can meet an infrastructure problem.

Here is the twist. The market is not rewarding ambition in the abstract. It is rewarding evidence that ambition can survive contact with the grid.

Houston. Photo: Jim Evans / Wikimedia Commons, CC BY-SA 4.0.

Why investors release money in stages

Milestone-based financing can sound like a fussy investor habit. It is actually a consequence of how investment funds work.

An equity investor buys a stake in a company because it expects that stake to become much more valuable. But that investor also has a time horizon. It needs the company to make visible progress while the fund still has time to support it, value it and eventually realise a return. A vague plan to solve technical, customer, permitting and grid problems over an unknown period is difficult to support, however elegant the science.

Debt works differently. It must be repaid. So its provider is less interested in a distant possibility of a valuable company and more interested in whether a defined asset or business can generate enough dependable cash to meet its obligations. That is why debt is generally a poor match for unresolved technology risk, but can become relevant once performance, development and operating risks are clearer.

This is where most people stop looking. They see an investor decline and assume the investor doubts the sector. Often, the investor may simply be unable to carry that risk for that long, at the return it needs.

That is why a milestone matters. It compresses uncertainty into a test.

For Fervo, stable flow and 3 MW of baseload generation were not merely impressive engineering results. They helped translate a difficult technical claim into operating evidence. That made it easier to use a mixture of equity, debt and grants rather than demanding that early equity investors finance every later stage as well.

The clause nobody sees: the next investor

A founder may believe a large first round is the goal. It is not. The goal is to reach the next financing event before the current money, and the patience behind it, are exhausted.

The International Energy Agency reports that 40% of US energy startups raised a second round within two years between 2010 and 2025, compared with 30% in Europe. It also found that 40% of first US energy rounds exceeded $10 million, against a 25% average across 2015 to 2024.

That makes the United States look generous. In one sense, it is. US energy startups can access larger early rounds and more often reach a second round than European peers.

But there is a catch. A bigger first cheque can create a bigger expectation of progress. If the money was meant to prove a pilot, secure customer demand, advance permitting or establish a grid pathway, the next investor will expect to see that result. Not a revised explanation for why it took longer.

Net Zero Insights found that US clean-energy and industrial-innovation capital was concentrating into fewer, larger rounds in the first half of 2025, while later-stage resilience through debt and scale capital was rising. The bind is obvious: companies need money to reach milestones, but milestones are what unlock the money.

Put Fervo, the US round data and that concentration trend side by side, and a pattern appears that none of the reports says outright. The scarce resource is not capital alone. It is credible progress at the speed capital requires.

A pipeline is not a project

For renewable developers, the decisive milestone may not be a technical pilot at all.

Roland Berger reports that post-2025 policy shifts, Federal Energy Regulatory Commission queue reform, tax-incentive phase-out and inflationary costs have increased development costs and interconnection timelines in the US. This has favoured larger platforms with execution capacity. Early-stage pipelines have lost value unless they hold privileged interconnection positions or strong execution teams.

A grid queue position is a project’s place in the process for seeking connection to the electricity grid. It is an awkwardly bureaucratic phrase for something brutally important. A project that cannot connect cannot reliably deliver power, however attractive its projected output may be.

The American Council on Renewable Energy reached the same uncomfortable territory from the investor side. Its 2026 to 2029 outlook found investors expecting increased investment in 2026, while identifying policy, regulation and interconnection uncertainty as their largest risks afterwards. Interest remained strongest in utility-scale solar and storage. Yet interest is not deployment.

That overturns another comforting assumption: a large pipeline is proof of value. It may be evidence of opportunity. It is not necessarily evidence that a project can be built, connected and operated.

A smaller portfolio with a better route through permits and grid access can be more financeable than a much larger portfolio still waiting in line.

Choose the money by the risk

Imagine an illustrative early-stage US energy operator with four needs: prove a new system works, pay for permit and interconnection work, secure a customer commitment, and eventually build an asset.

It should not automatically raise one giant equity round.

If the central uncertainty is whether the system works at all, equity is the natural candidate. Equity investors are taking company risk: the technology, team and commercial possibility. The operator should define a technical milestone, such as the operating evidence that would make the next discussion materially easier.

If the work is eligible for grant support, a grant may be the better tool for that defined proof activity. It does not require giving away ownership, but it must match what the grant provider is prepared to fund. How do people get small startup grants? Start with what the funder buys is useful reading here, because the application begins with the funder’s purpose, not the founder’s preferred story.

If the missing piece is a customer commitment or practical delivery capacity, the operator should test a strategic partner. The right partner is not simply a famous name. It is one that removes the particular commercial or execution risk blocking the next financing.

Debt should wait until the business or a specific project has enough clarity for repayment to be credible: clearer development, expected output and a route to operation. Asking debt to fund an unproven technical leap is usually asking the wrong capital to do the wrong job.

That is a concrete decision rule: choose equity for unproven company risk; grants for eligible proof work; a partner when market access or execution is the missing evidence; debt when there is a sufficiently defined route to repayment. In practice, the sequence can be blended, as Fervo’s mix shows. But the risks should not be blended into one vague ask.

Federal Energy Regulatory Commission. Photo: Nuclear Regulatory Commission from US / Wikimedia Commons, CC BY 2.0.

Where the lesson breaks

Not every milestone can be rushed by better financing structure.

Policy, permitting and interconnection uncertainty can remain outside a founder’s direct control. Roland Berger’s account of developer consolidation shows that some companies responded through scale, merger or exit because the market increasingly favoured execution-capable platforms. A disciplined risk map does not create a privileged queue position.

Nor does staged capital guarantee follow-on money. It simply gives the company the best chance of presenting the next investor with a smaller, clearer risk than the last one saw.

That is still a major advantage.

What operators should do before the next raise

Start with one page, not fifty slides. List the remaining risks: technology, customer demand, permitting, interconnection, construction and operating performance. Then ask four questions of each one.

What evidence would reduce it? What will that evidence cost? Which capital source can sensibly fund it? And which future investor becomes more likely to engage if it is achieved?

The resulting raise should be specific. “We need capital for growth” tells an investor almost nothing. “We need capital to produce the operating proof required before project-level funding can be assessed” is a financing proposition.

It also changes how a founder handles the process. What is the process for applying for funding? It is not the deck makes the essential point: materials matter, but the underlying proof and sequence matter more.

GI Network would turn that risk map into an investment case built for the actual next decision. That means separating company funding from project funding, testing whether projected cash flows can support debt when the time comes, identifying the evidence each capital provider will require, and rehearsing the objections an investment committee is likely to raise. The aim is not a bigger list of investors. It is a structure that gets the operator to a genuinely financeable next milestone.

The handover test

Before taking any energy financing to market, use the Handover Test.

H: Hold the risk still remaining. Name the single risk that matters most now.

A: Assemble the proof. Define the technical, customer, grid, permitting or operating evidence that would reduce it.

N: Name the right capital. Match equity, debt, grants or a partner to that risk, rather than treating all money as interchangeable.

D: Decide who comes next. Identify the next investor and the evidence that investor will need.

O: Own the timetable. Test whether the current capital can reach the milestone within its investors’ time horizon.

V: Verify project readiness. For assets, examine interconnection, permits and execution capacity before celebrating pipeline size.

E: Explain the relay. Show every investor how this money creates the conditions for the next handover.

Fervo’s lesson is not that every founder needs a billion-dollar outcome. It is simpler, and more useful. Make one important uncertainty smaller. Then raise the money that is designed to live with what remains.