Sustainable Bottom Line: Clean energy is the theme that characterizes the top performing sustainable funds, led by common holdings that gained between 30% and 72%.
Notes of Explanation: The top 10 performing sustainable funds in September and their total return performance results, include: Global X Hydrogen ETF (29.35%), Direxion Daily Electric and Autonomous Vehicles Bull 2X ETF (25.76%), VanEck Green Metals ETF (17.65%), ProShares S&P Kensho Cleantech ETF (16.55%), Amplify Lithium & Battery Tech ETF (16.15%), SPDR Kensho Clean Power ETF (15%), Xtrackers Semiconductor Select Eq ETF (14.67%), Victory Global Energy Transition Y (14.53%), Invesco WilderHill Clean Energy ETF (14.53%), and Global X CleanTech ETF (14.52%). For mutual funds with multiple share classes, only the best performing share class is considered. Sources: Fund documents, Morningstar and Sustainable Research and Analysis LLC.
Observations:
• Clean energy, which generally refers to energy derived from renewable, low-carbon, or zero-emission sources, including technologies and infrastructure that generate, transmit, store, or improve the efficiency of energy in ways that reduce greenhouse gas emissions relative to conventional fossil fuels, and cover pure play companies, enablers and diversified players, is the theme that characterizes the 10 best performing sustainable funds in September 2025. The group, consisting of nine index tracking ETFs and one actively managed mutual fund that, on a combined basis, account for some $1.6 billion in net assets, posted an average gain of 17.9% in September and 36.35% over the trailing 12 months. By way of comparison, focused sustainable US equity funds gained an average of 2.25% in September and 10.85% over the trailing 12 months while the S&P registered increases of 3.65% and 17.6%, respectively.
• The common macro tailwinds that drove the results achieved by the 10 best performing sustainable funds were (i) the broad September equity rally, (ii) falling rate expectations after the Fed’s mid-September move, supportive for long-duration growth themes, and (iii) a powerful narrative shift around clean-power reliability for AI data centers that turbo-charged hydrogen/fuel-cell names and several clean-tech sub-themes. Hydrogen fuel cell maker Bloom Energy (BE) alone jumped around 60% in September based on the AI-power story, with sympathy rallies across fuel-cell peers. That said, some of the firms in this category, such as Ballard Power (BLDP), trade at prices below $10 per share so small price moves produce large percentage changes.
• Bloom Energy has been on a tear this year. The stock gained almost 300% this year (to 10/10/2025), 20% of which occurred in September. According to an RBC Capital research note, a filing by BFC Power involving an application in Wyoming for approval to construct a power plant with a total capacity of 900 megawatts is to be powered by Bloom Energy’s fuel cells. The stock was the most widely held among the 10 best performing funds, with five funds maintaining positions in BE that ranged from a high of 23.5% of assets by the $53 million Global X Hydrogen ETF to a low of 3% of assets by the $78.6 million Amplify Lithium & Battery Technology ETF.
• Bloom Energy aside, the other most widely held stocks, for a total of five stocks based on number of fund holdings, are Ballard Power (BLDP), a developer and manufacturer of proton exchange membrane fuel cell products for markets such as heavy-duty motive, portable power, material handling as well as engineering services, EOS Energy (EOSE), a firm that designs and manufactures zinc battery storage systems, rather than lithium-ion batteries, that are fully recyclable, nonflammable, and a scalable alternative for use in utilities, commercial, and industrial sectors, Fluence Energy (FLNC), a firm that builds grid-scale battery systems that store renewable energy for when the sun doesn’t shine or the wind doesn’t blow, a critical capability for data centers that require constant, reliable power, and Plug Power (PLUG), a company engaged in the development of hydrogen fuel cell and electrolyzer systems that replace conventional batteries in equipment and vehicles powered by electricity. Each of these stocks gained between 30% and 72% during the month of September.
