Top 20 private equity firms’ portfolios pollute more than most countries, research finds

A new report reviewing the 20 largest private equity firms finds that their energy portfolios generate about 1.5 billion tonnes of greenhouse gases each year, more than the annual emissions of almost any country. The firms manage $7.3trn in diversified assets, and according to the report, they could shift away from fossil fuels without significant damage to their broader holdings. Instead, their energy investments include a large number of fossil fuel assets, including natural gas and coal-fired power plants. Collectively the firms own about 15,000 miles of pipelines, 124 gigawatts of power generation capacity and hundreds of oil and gas fields.

The data centre sector is a central focus of the findings. Private equity backs five of the top ten US data centre owners, making it the largest data centre-owning sector outside big tech. Private equity investment in US data centres reached $45.7bn in 2025, about 72% of total sector investment. The report notes that Blackstone invested $2.16bn in Northern Indiana Public Service Company (NIPSCO) in 2024, which has since announced plans for a 2,300 MW natural gas power plant to serve data centres. The report also states that BlackRock, GIP, Energy Capital Partners, EQT and Kayne Anderson increased their fossil fuel holdings since 2024.

Returns on completed private equity oil and gas funds were weak, according to the report. The 145 funds received $190.4bn in contributions and returned $192.9bn, a gain of about 2%. After inflation, investors largely lost money on average. None of the 20 firms scored an A on current energy portfolios and policies, and only three received a B. The report also links air pollution from PE-backed extraction, coal plants and LNG infrastructure to at least 1,000 premature deaths.

The report recommends that firms disclose fossil fuel holdings and emissions, adopt science-based climate targets, publish portfolio-wide transition plans and increase transparency around political spending and climate lobbying. Amanda Mendoza, senior research and campaign coordinator at PESP, said that the investments produce emissions on the scale of a major country and that many oil and gas funds have failed to generate strong returns for pensions and other investors while firms continue collecting fees. Alex Hurley, project manager at GEM, said the scorecard provides clear evidence for fund managers and investors to choose their risk level in a rapidly changing climate. Dustin Duong, research associate at Americans for Financial Reform Education Fund, said the industry is doubling down on data centres and dirty energy.