Global funding for work on solar geoengineering has grown by more than 11 times over the past decade, reaching a total of $267 million through 2025, but the sources of that funding are shifting, according to new data from SRM360.
Philanthropy, commercial actors, and the UK government account for an increasingly large share of recent and committed funding, while other governments are falling back. This shifting balance of funding has significant implications for the future development of the field.
As climate change intensifies, growing attention is being paid to new technologies that could cool the planet by reflecting sunlight to space – collectively known as solar geoengineering or sunlight reflection methods (SRM).
Philanthropic sources are now the largest source of funding for work on solar geoengineering (38% of the total through 2025); governments are second (33%), with commercial funders third (29%) after large investments in the for-profit Israeli-American company Stardust ($75 million in total).
More than 99% of funding through 2025 came from countries in the Global North, and organisations based in the Global North also received 97% of the total.
Looking ahead, philanthropic sources account for around two-thirds of all known funding committed from 2026 onwards, with the other third from governments. 94% of committed government funding comes from just one country – the UK – mainly through its Advanced Research + Invention Agency (ARIA).
The findings update SRM360’s inaugural global analysis of SRM funding flows, first published in 2025. SRM360’s Funding Tracker remains the most comprehensive publicly available resource for tracking SRM funders and recipients by country, sector, and activity.
> See the updated funding analysis and downloadable graphics here, read about the latest developments here, and explore the interactive tracker here.
Top findings from SRM360’s new funding data include:
- SRM funding has risen sharply over recent years, reaching a total of $267 million through 2025. Funding was 11 times larger in the five years from 2021–2025 ($214 million) compared to ten years earlier in 2011–2015 ($19.2 million).
- Through 2025, philanthropic funding was the leading source at $102 million, or about 38% of the total. That was followed by governmental sources ($87.5 million, 33%) and Stardust’s backers and other minor commercial sources ($77.5 million, 29%).
- $154 million has already been publicly committed from 2026 onwards. Philanthropic sources account for $101 million, or 66% of the known total.
- Only $7.8 million of total funding through 2025 has gone to the Global South, with another $15 million committed for the coming years.
- Governmental sources account for the remaining 34% of committed future funding, but 94% of that comes from just one country, the UK. The US government provided $26.2 million through 2025 but has just under $400,000 of known funding allocated from 2026 onwards.
- While funding for work on solar geoengineering has rapidly risen, now averaging around $44 million per year over the past 5 years, it remains relatively small, amounting to only 0.3% of annual climate philanthropy (roughly $15 billion per year) and 0.002% of annual clean energy investments (around $2.2 trillion per year).
Quotes:
“It’s striking that only a handful of people – at a few philanthropies, government funding agencies, and one start-up – are determining the direction of solar geoengineering research. Given the potentially world-changing nature of this technology, it’s surprising that only the UK government is publicly supporting serious research into this topic.” – Dr Pete Irvine, SRM360 Chief Scientist and Co-Founder.
“Decisions taken today about solar geoengineering could lock in outcomes for generations to come. Access to clear, accessible information about who is funding it, and where, plays a critical role in its effective governance.” – Mark Turner, SRM360 Chief Communications Officer and Co-Founder.
