How to compare the best green energy suppliers in the UK

Tracked suppliers: existing editorial scores

Scores out of 100, not environmental certifications. The tracked list is not the whole market.

There is no single green winner for every household

The best supplier depends on what you want to support, the tariff you can actually obtain and the quality of service you need. Renewable-matched electricity, investment in generation, green gas and lower household consumption are different objectives. Do not treat a green label as proof that all of them are delivered by the same offer.

The comparison below uses the existing Supplier Monitor list and its published editorial scores. It is not a new environmental rating or a claim that every listed supplier is a specialist green supplier. Read the score date and methodology, then examine current fuel-mix and tariff documents before deciding. A high service score can help with practical confidence, but cannot establish the environmental effect of a tariff.

What REGOs establish

A Renewable Energy Guarantee of Origin is a certificate associated with electricity generated from a renewable source. Suppliers use certificates to support renewable matching and fuel-mix reporting. Electricity arriving through the shared grid is not physically routed from a named wind farm exclusively to your socket. Separate the accounting claim from the physical electricity mix at the time you use power.

A REGO can support a renewable-origin claim without, by itself, showing that your purchase financed a new project. Ask how the supplier obtains its certificates and what the published tariff terms promise. Avoid the opposite shortcut too: certificate-backed reporting is not automatically evidence of deception. The important question is whether the marketing says more than the supporting documentation establishes.

Direct contracts and owned generation

A supplier may purchase electricity through a direct power purchase agreement with a generator, invest in generation or own generating assets. These arrangements differ from buying certificates independently. Ask which arrangements apply to the tariff you are considering, where the generation is located and what period the disclosure covers. Do not assume a parent company’s assets describe every retail tariff.

Ownership alone does not quantify how much new renewable capacity your decision supports. A direct agreement may provide evidence about purchasing relationships without proving a particular additional environmental benefit. Look for specific, dated statements rather than an unsourced green score. Our existing green-tariff explainer covers the concepts; the linked greenwashing article helps you question claims without inventing an environmental ranking.

Use the tracked supplier comparison carefully

The table shows the same tracked suppliers as Supplier Monitor, including service, transparency and overall editorial assessments. It is not a complete list of every UK supplier and should not be read as a league table of renewable generation. Follow each supplier’s scorecard for weaknesses, context and the date attached to its existing scores.

For a short list, record which suppliers satisfy your meter and tariff requirements, then add a separate evidence column for current fuel mix, renewable purchasing and generation disclosures. Leave that column unanswered when evidence is missing. A blank is more useful than a made-up certification. We have not copied the older guide’s illustrative annual green premiums into this comparison or presented them as current quotes.

Check electricity and gas separately

A renewable electricity claim does not establish that the gas on a dual-fuel tariff is renewable. Gas descriptions can refer to biomethane, carbon offsets or a mixture of conventional gas and another accounting arrangement. Ask for the actual claim, its scope and the evidence behind it. Burning conventional gas does not become the same process as renewable electricity generation because a tariff is labelled green.

Where offsets are included, check the scheme and the supplier’s explanation rather than assuming the word “neutral” means no emissions occur. Do not compare an electricity-only renewable claim with a dual-fuel marketing claim as though both cover the same thing. If environmental impact is your priority, keep the separate electricity and gas evidence visible alongside the total annual price.

Compare the bill and practical terms

Use your annual electricity and gas kWh to price the quotes. Include standing charges, contract length, exit fees, payment requirements and any optional green add-on. A fixed premium copied from an old article would not describe a current quote, so this guide does not supply one. The energy bill calculator can compare single-rate figures you obtain yourself.

Check support for your smart meter, any export tariff if you have solar and whether an advertised time-of-use product fits your equipment. The best environmental description does not make an unsuitable meter arrangement useful. Keep service evidence separate from pricing, and avoid switching solely on a single favourable score or a renewable percentage without understanding the full terms.

Make a decision you can explain

Create a brief record of the current tariff quote, your annual-cost calculation and the green evidence that matters to you. Read the supplier’s own fuel-mix disclosure and ask a specific question if the claim is vague. If it cannot be substantiated, do not fill the gap with an assumed benefit or a fabricated ranking. You can choose a different tariff or ask for clearer evidence.

PowerGuardian may earn commission when readers follow clearly labelled partner links on linked supplier pages. Commercial arrangements do not influence the existing scores or rankings. This guide adds no supplier affiliate button and promises no guaranteed environmental or financial saving. Your next step is to inspect the relevant Supplier Monitor scorecard and compare a dated quote with the evidence behind its green claim.