Who Funds Work on Solar Geoengineering?

As climate change has continued to worsen, interest in SRM as a potential method to reduce some of its impacts has grown. More interest means more money – and how money is spent can determine the directions a field takes. Here, we provide an overview of our updated analysis of the funding into SRM – you can find details of the methods behind this analysis here, and read more about some of what’s new this year here.

Global funding for SRM has risen sharply in recent years

Funding for SRM reached a cumulative total of $267 million through 2025 and was 11 times larger in the five years from 2021–2025 ($214 million) compared to ten years earlier in 2011–2015 ($19.1 million). Adjusting for inflation, that is more than 8 times larger ($221 million vs. $26.4 million). This growth is likely to continue, as a total of $154 million has already been publicly committed from 2026 onwards.

For much of the last two decades, most of that has gone to research (51%), mostly at universities, and to non-profits working on awareness-building and advocacy (21%). The recent entry of the for-profit US-Israeli company Stardust Solutions has altered the landscape significantly. Having raised a total of $75.0 million, Stardust has now received 28% of all known SRM funding to date.

Though the funding for SRM is growing, the absolute amounts remain small relative to spending on other climate policies. A report from Climateworks estimates that philanthropic funding for climate mitigation totalled around $15 billion in 2024, compared to only about $44 million per year in overall funding for SRM between 2021 and 2025. Furthermore, investments in clean energy topped $2 trillion in 2025, according to the International Energy Agency – average annual SRM funding comes to just 0.002% of that amount.

Philanthropic funding is leading the way, but commercial funding is rising

Through 2025, philanthropic funding was the leading source at $102 million, or about 38% of the total. That is followed by governmental sources in second place ($87.5 million, 33%) and commercial sources in third ($77.5 million, 29%).

Looking ahead from 2026, philanthropic sources have committed an additional $101 million, accounting for about 66% of the known total of future funding. Governmental sources account for the other 34% of committed funding, with almost all of that ($49.3 million, or about 94%) coming from one country, the UK, while the EU, France, and the US have committed much smaller amounts.

A small portion of funding to date – less than $200,000 – has come from sources we cannot confidently identify. However, it should be noted that there are SRM funders and organisations that have not shared their full funding information with us and there may be other funders and organisations that we are unaware of. Organisations that devote a small fraction of their work to SRM, such as the Heinrich Böll Foundation, are also not included in our funding total.

That said, we have not found any evidence of fossil fuel interests funding SRM activities. There are concerns that such interests might support SRM as a potential way to stave off decarbonisation, though, as yet, they do not appear to be doing so by funding research or organisations working on the topic.

A small number of countries and philanthropies dominate SRM funding

In terms of funding for the field, a few countries and philanthropies dominate. The UK,¹ US, Australia, Germany, and the European Union have provided the vast bulk of total government funding through 2025 ($80.3 million, or about 92% of the total). The Simons Foundation, the Quadrature Climate Foundation (QCF), and Coefficient Giving (formerly Open Philanthropy), have led the way among philanthropies ($51.6 million combined, or just over 50% of all philanthropic funding through 2025).

Looking ahead, only the UK has committed significant amounts of government funding to SRM, at $49.3 million from 2026 forward; the EU ($2.3 million), France ($861,000), and the US governments ($397,000) have committed smaller amounts. QCF has another $34.7 million committed from 2026 onwards, followed by the Simons Foundation with another $29.4 million – both outpacing every government in the world except for the UK, at least based on what is known so far.

On the commercial side, Awz Ventures, a Canadian-Israeli-US firm with ties to defence agencies, supported Stardust in 2023 with $15.0 million. With additional investors from the US, UK, and across Europe, its 2025 fundraising round brought Stardust’s total investment to $75.0 million.

The Global North dominates, though research is expanding around the world

If SRM is ever deployed at planetary scale, the resulting changes to the climate would affect everyone on earth. Countries in the Global South are generally among the most vulnerable to the changing climate and may have the most at stake with SRM – but the Global North has dominated the funding that shapes the field.

More than 99% of the funds provided came from countries in the Global North – about $265 million versus $1.8 million. The Global North also received 97% of the total. Still, $7.8 million in funding has flowed to 22 countries in the Global South, in large part from the non-profit Degrees Initiative. This organisation plans to continue funding researchers in the Global South, with $5.1 million in future funding commitments.

The world’s second-largest economy, China, has publicly reported just $1.8 million in SRM funding, with no known plans for further investment, though information is generally scarce. Organisations in India have received small amounts of SRM funding (just over $200,000), but we have not seen evidence of government spending in the world’s most populous country.

In an age of increasing geopolitical competition – including for technological dominance – how will different powers respond to this mismatch? Efforts to create multilateral governance over geoengineering have been slow. Without it, countries may see a rising interest in determining who has their hand on a potential global thermostat.