Want an energy supplier that fits your budget AND your values? We’ve compared five providers to help you find a home for your energy bills that you can feel good about.
There comes a point in autumn when putting the heating on brings a little mental calculation with it. How much is this going to cost, and could we be getting a better deal?
This October, that question feels particularly timely. Ofgem’s energy price cap rose by four per cent for a typical household paying by direct debit, just as we head towards the colder months. The cap limits rates on covered tariffs, rather than your total bill, so what you pay still depends on how much energy you use.
If you’re thinking about switching, you might also want to know what your money supports. Choosing a supplier that invests in renewable energy can feel like a positive use of a bill you have to pay anyway.
Working out which companies live up to their green promises takes some effort, though. A renewable electricity tariff might tell you very little about the company’s gas supply, its wider business or how helpful it will be when something goes wrong.
We’ve done the digging on five energy suppliers, looking at where your money goes, how they treat customers and what their green claims mean, to help make your choice easier.
How we use the Good Money Test
We’ve adapted the Good Money Test for energy suppliers. It asks five questions:
- Where does your money go? Does the company support renewable energy, and does its wider business have fossil fuel interests?
- Can you see what is happening to it? Does it explain where its energy comes from and what you’re paying for?
- Is it doing any good? Is it helping to build renewable energy or making it easier for households to use less fossil fuel?
- Are customers treated fairly? Does it offer clear information, helpful service and support when people need it?
- Do the actions back up the claims? Is there evidence behind the green promises?
Our verdicts reflect the published information we’ve reviewed, including suppliers’ disclosures and independent customer research. A pass with reservations means there are worthwhile strengths alongside drawbacks we think you should know about. These assessments are separate from our Good Egg accreditation.
Green energy suppliers at a glance
| Supplier | Why consider it? | What to know | Good Money Test |
|---|---|---|---|
| Good Energy | Buys renewable electricity directly from British generators | Most of its gas is still fossil fuel, and ownership has changed | Pass, with reservations |
| Ecotricity | Uses customers’ bills to help build renewable energy projects | Customer service results are less reassuring | Pass, with reservations |
| 100Green | Offers a tariff with 100 per cent certified green gas | Other tariffs contain a smaller proportion of green gas | Pass, with reservations |
| Octopus Energy | Offers practical options for EVs, heat pumps and cheaper off-peak electricity | Its published electricity mix includes nuclear power | Pass, with reservations |
| So Energy | Another renewable electricity option to compare on price | Its parent company still has substantial fossil fuel activities | Pass, with reservations |
Good Energy: knowing what your money supports
Good Energy is worth considering if you want a clear connection between your electricity bill and British renewable energy.
It buys renewable electricity directly from more than 3,300 British generators, matching the amount its customers use over a year.
It also checks how closely that generation matches customers’ electricity use throughout the day. For April 2025 to March 2026, it reports an 87 per cent match within the same half hour. That is useful because the country needs renewable power available when people are actually using it.
Its gas needs a little more explanation. At least 10 per cent is biogas, made from organic materials such as waste. Most remains fossil gas, with the company buying carbon offsets to compensate for emissions. Those offsets support projects elsewhere; they don’t make the gas itself renewable.
Good Energy also has a new owner. Esyasoft bought the business in April 2025, so its long-standing environmental reputation needs to be considered alongside its place in a wider group.
Good Money Test verdict: Pass, with reservations. Buying directly from renewable generators and explaining its energy sources are clear strengths. Customer feedback is encouraging, although independent checks of how it runs its service were less positive. We’d also keep its new ownership and continued use of fossil gas in mind.
Ecotricity: helping build more renewable energy
With Ecotricity, part of the appeal is knowing that money from customers’ bills helps develop new sources of renewable power.
The company builds wind and solar projects, giving its environmental promises something tangible behind them. It also considers animal welfare: its energy is certified vegan by the Vegan Society and Viva!, excluding animal-derived materials from its energy sourcing.
Its gas supply contains a mixture of sustainable green gas and fossil gas. The company also invests in British carbon removal projects, but customers shouldn’t assume that all the gas they buy is renewable.
Service is another consideration. Ecotricity received two stars out of five for overall customer service in Which?’s 2026 survey. That matters when you need someone to explain a bill or put a mistake right.
Good Money Test verdict: Pass, with reservations. Its investment in renewable generation and clear animal-welfare standards give it a strong environmental case. Customer service is the main reservation. It could suit someone who particularly values helping to build renewable energy and is comfortable with the price they’re quoted.
100Green: a choice for greener gas
If you have gas central heating, 100Green offers something worth looking at: a tariff with 100 per cent certified green gas.
That tariff is called 100 Origin. Its other tariffs include at least 10 per cent green gas, so the name of the company alone won’t tell you what you’re getting.
Green gas is produced from organic materials and processed into biomethane, which can be fed into the gas network. Your home still receives the shared network supply, but your purchase supports renewable gas production.
100Green also explains where its renewable electricity comes from. Its 100 Origin tariff includes extra environmental requirements for generators, such as protections for wildlife.
Customer feedback is a positive part of the picture, although independent research found room for improvement in support for people who need extra help.
Good Money Test verdict: Pass, with reservations. Clear information about its energy sources and the option of fully certified green gas give 100Green a credible environmental case. Choose the tariff carefully, check the cost and, if you need additional support, make sure its arrangements work for you.
Octopus Energy: making greener choices easier at home
Octopus Energy is worth comparing if you have an electric car, solar panels or a heat pump, or can move some electricity use to cheaper times of day.
It offers tariffs designed around those needs, alongside services such as solar panel and heat pump installation. Its wider business also invests in renewable generation, and independent research gives it recognition for both sustainability and customer service.
One detail needs explaining. On its green energy page, the published electricity mix for April 2024 to March 2025 is 86.4 per cent renewable and 13.6 per cent nuclear.
Nuclear power produces low-carbon electricity, but it isn’t renewable. That distinction may matter to you when choosing a supplier.
The other question is whether a particular tariff fits your home. Cheap overnight electricity can be useful for charging a car, for example. You still need to account for what you’ll pay during the rest of the day.
Good Money Test verdict: Pass, with reservations. Its renewable investment, customer-service recognition and practical help for households are positives. Our reservations are about the distinction between renewable and nuclear electricity, and making sure a specialist tariff delivers savings for the way you live.
So Energy: an option with a wider business to consider
So Energy backs its renewable electricity through contracts with generators and certificates that verify renewable production. Customers can also vote for the renewable sources they would like it to support.
It is another option to compare if you want renewable electricity at a price that works for your household.
However, So Energy belongs to ESB. The wider group’s 2025 sustainability report records substantial fossil fuel use alongside its renewable activities. That is relevant if you want your supplier’s whole business to be moving away from fossil fuels.
Customer feedback was generally positive in the independent research we reviewed, but checks covering areas such as complaints, contact and support were less reassuring.
Good Money Test verdict: Pass, with reservations. So Energy explains how it supports renewable electricity, but its parent company’s fossil fuel activities and weaknesses in its service assessment limit our endorsement. It may appeal if you receive a competitive quote and are comfortable with those compromises.
What does a green tariff actually change?
Your electricity reaches you through the same shared grid as your neighbours’. Choosing a green supplier affects how the company supports the energy you buy.
Suppliers can use certificates called Renewable Energy Guarantees of Origin, or REGOs, to show that renewable electricity has been generated to match customers’ use.
Those certificates provide evidence, but they don’t tell the whole story. We also look at whether a supplier buys directly from renewable generators, helps build new projects and explains its activities clearly.
Gas is worth checking separately. A company can offer renewable electricity while selling mostly fossil gas. Look for the proportion certified as green gas, and remember that carbon offsetting does not change the source of the fuel.
How to choose a deal that works for you
Start with the amount of electricity and gas you use in a year, measured in kilowatt hours. You’ll find this on your bill or in your online account. Using the same figures for each quote makes the comparison much more useful.
Compare the estimated annual cost, including the daily standing charges, and check for exit fees. A lower suggested monthly direct debit might simply be based on an assumption that you’ll use less energy.
If you’re considering a fixed tariff, it is the agreed rates that are fixed. Your bill can still increase if you use more. For tariffs with cheaper and more expensive hours, think honestly about how much of your routine you can shift.
You don’t need an electric car or a house full of new technology to make a worthwhile choice. Nor should choosing greener energy leave you struggling to pay the bill.
A supplier that fits your budget, explains itself clearly and puts your money towards something you value is a good place to start.
