Top 10 US Clean Energy Technology Companies

A Stanford University spin-off founded in 1985 that has installed solar on 650K+ homes across 15GW of residential projects. Acquired Maxeon Solar Technology and operates the SunPower Financial leasing arm for zero-down installations, cutting upfront costs by 100% compared to typical purchase.

A solid-oxide fuel cell manufacturer with $1.3B revenue in 2023 and 1GW+ of always-on clean power systems deployed globally. Its Energy Servers run on natural gas, biogas, or hydrogen to provide 24/7 baseload electricity without intermittency. Deployed at Apple, Google, and AT&T to decarbonize critical facilities.

The US offshore wind arm of Danish clean energy giant Orsted, with a 15GW US development pipeline making it the leading offshore developer in American waters. Co-developing Vineyard Wind 1 — the first commercial-scale US offshore wind project — off Martha's Vineyard, Massachusetts.

The iron-air battery startup that has raised $800M+ to commercialize 100-hour grid-scale energy storage — a potential breakthrough for solving renewable intermittency. Its iron-air chemistry costs a fraction of lithium-ion at scale. Building its first gigafactory in Weirton, West Virginia with DOE backing. This technology offers a 30% lower levelized cost than lithium-ion batteries and lasts 50% longer per cycle compared to the industry standard for long-duration storage.

A residential solar and battery storage-as-a-service provider with $660M revenue and 400K+ customers across 45+ US states and territories. Offers zero-down solar leases and power purchase agreements with 25-year performance guarantees. Partners with 1,000+ local solar dealers as its nationwide distribution network.

An AI-driven energy storage optimization company with $100M+ ARR and 1GW+ of battery assets under management across 200+ clients. Its Athena AI platform forecasts energy prices and dispatches storage to minimize costs and maximize revenue, achieving 20% higher savings than the average industry platform. Serves utilities, C&I customers, and renewables developers across 9 countries.

Operates a 6.2GW fleet of solar systems under long-term leases and PPAs, generating recurring revenue for 20+ years, and its fleet capacity is 50% larger than the runner-up SunPower. Acquired Vivint Solar in 2020 for $3.2B to double its installed base overnight.