Ranked by the ClimateTicker Green Score — who genuinely helps, and who to watch.
Climate Software · San Francisco, CA, USA
Enterprise carbon-management platform that helps large companies measure, report and reduce emissions across their operations and supply chains.
Carbon Removal · Zurich, Switzerland
Swiss pioneer of direct air capture (DAC), removing CO₂ from the atmosphere and storing it permanently underground, including the Orca and Mammoth plants in Iceland.
Solar · San Francisco, CA, USA· RUN
Largest residential solar, battery storage and energy-services company in the United States, offering home solar through subscription and ownership models.
Energy · London, UK
UK-based clean energy retailer and technology group whose Kraken platform manages renewable supply, smart tariffs and grid flexibility for millions of customers worldwide.
Transport · Irvine, CA, USA· RIVN
American electric vehicle manufacturer producing adventure-focused trucks and SUVs, plus commercial electric delivery vans, with a vertically integrated software and charging ecosystem.
Energy Storage · Somerville, MA, USA
Develops low-cost, multi-day iron-air battery storage designed to keep the grid reliable as it shifts to wind and solar, storing energy for 100+ hours.
Advanced Materials · San Jose, CA, USA
Advanced materials company commercialising lithium-sulfur batteries and 3D graphene applications that promise lighter, cheaper energy storage with a lower carbon footprint.
Nature & Carbon Markets · San Francisco, CA, USA
Uses satellite data and machine learning to verify and monitor forest carbon projects, bringing transparency and quality to nature-based carbon markets.
Energy · Devens, MA, USA
MIT spin-out building compact tokamak fusion reactors using high-temperature superconducting magnets, targeting commercial fusion power with its SPARC and ARC machines.
Food & Agriculture · El Segundo, CA, USA· BYND
Plant-based meat producer whose products aim to cut the land, water and emissions footprint of animal agriculture while matching the taste of conventional meat.
Power Generation · Selby, UK· DRX
UK power generator that converted its coal plant to burn wood-pellet biomass, which it markets as renewable and 'carbon negative' — a claim widely contested by scientists and journalists.
Oil & Gas · Spring, TX, USA· XOM
One of the world's largest publicly traded oil and gas companies, with growing upstream production alongside a comparatively small low-carbon solutions division.
Aviation · Dublin, Ireland· RYAAY
Europe's largest low-cost airline by passenger numbers, which has marketed itself as a low-emissions carrier despite being one of the continent's biggest single CO₂ emitters.