49 UK companies have promised to run on clean electricity. How do they really score?

Switching to renewable electricity is a good start. For most companies, it's also the smallest part of the problem.

What is RE100?

RE100 is a group of businesses that have each promised to use 100% renewable electricity. It's run by the Climate Group, a climate charity, with CDP, which runs a global environmental reporting system. 49 of its members are headquartered in the UK, including Tesco, HSBC, Unilever, Sky and Heathrow.

What we did

SINK is an independent sustainability score. We score every company out of 100 using the same ten questions:

• how much it emits, and whether that's falling
• how clean its energy is
• what targets it has set
• its effect on nature, water and waste
• how openly it reports
• its record on controversies

The evidence comes from each company's own reports and filings, and from independent sources such as regulators, campaign groups and the press. Every source is linked on the company's page, so you can check our work. Companies can't pay to change their score.

We scored all 49 UK members.

Why clean electricity isn't the whole story

Clean electricity covers one of our ten questions. And for most companies, the electricity they buy is only a small part of their footprint. CDP found that the emissions in a company's supply chain are, on average, 11.4 times bigger than the emissions from its own operations.

So a company can run every office and shop on renewable power and still leave most of its footprint untouched. That's what our scores pick up.

What we found

When we published, two reached 60: Freshfields, a law firm, and Pearson, the education publisher. They score 62/100 and 60/100 today.

21 more were making progress, scoring between 46 and 59.

The average across all 49 is 45 today.

Two had significant gaps:

The pattern is clear. The companies near the top tend to have smaller footprints, mostly offices and travel, so clean power and good reporting go a long way. The companies further down make, sell, build or lend. Most of their footprint sits in their products, supply chains or loans, and clean electricity barely touches it.

The banks

Five UK banks are RE100 members:

Their offices can run on clean power. But a bank's real footprint is the companies it lends to and invests in, and that's far bigger than anything its offices produce. That's where they lose points.

A couple of notes

• Mace's published emissions don't cover its whole footprint, so our standard deduction applies. Its page explains this.
• Gatwick's 2025 emissions table appears to be misprinted. We scored the figures as printed, and say so on its page.
• Scores can go down as well as up. When companies publish new reports, we score them again.

The full table

Today's scores, highest first. Every company links to its page, with the reasoning and every source.

Run a business?

Get your own score, free, at sinkproject.com/get-scored.

RE100 UK members: companies headquartered in the UK on the RE100 member list, October 2026. Scored in October 2026. CDP figure from "Transparency to Transformation: A Chain Reaction", CDP Global Supply Chain Report, February 2021.