Which new solar energy company is good

Ecotricity, Good Energy and Octopus Energy scored highly in our sustainability assessment of gas and electricity firms. How do British Gas, Ovo Energy and Scottish Power compare? We've assessed energy companies on a range of sustainability criteria. Three of them were named Which? Eco Providers for energy in 2024.

EDF Energy and E.ON Next are the joint-highest-ranked of the traditional big firms this year, with an overall score of 62%. British Gas has the lowest overall score. Feeling the pinch with energy bills?

Here's a quick comparison table of our best solar panel installers, with an overview of their warranties and how long they've been in business. Midlands-based Project Solar is the UK's largest solar installation company. It's also one of the most accredited and experienced, having carried out more than 45,000 installations since 2011.

Two energy providers – Ecotricity and Good Energy – hold the title for the fourth year in a row. Octopus Energy is an Eco Provider for the second time. At the other end of the spectrum, two gas and electricity suppliers scored zero points in our assessment. Energy companies approach renewable energy and sustainability in different ways.

Six energy firms dominated the market for decades until the major changes of the past couple of years. Four of the original six still supply more than half of energy customers today – British Gas, EDF Energy, E.ON Next and Scottish Power. Octopus Energy is now the largest supplier of electricity and the second-largest (after British Gas) for gas.

Recommended Providers. The Which? Recommended Providers for 2025 are: Octopus Energy, Utility Warehouse and 100Green. Our table below covers Great Britain. If you live in Northern Ireland, see our advice on NI electricity and gas firms.