The best green energy supplier in 2020: how to switch to renewable energy

Green energy reviews: Here are the best green energy suppliers of 2020 – and some will even save you money too

If you’re looking to switch to a green energy supplier, you have more choices than ever before as the market moves towards embracing renewable energy. Increasingly, it isn’t hard to find a supplier that can provide 100% green electricity. In fact, three of the Big Six energy companies – British Gas, npower and E-on – have tariffs that offer this. 

However, if you want green gas too – or at least a certain portion of it – then you’ll have to turn to one of the smaller energy suppliers. 

The good news? Green energy doesn’t have to cost you more: some of the cheapest energy suppliers we reviewed were green energy companies, with many leading challenger energy suppliers looking to entice customers with cheaper green tariffs too. 

Switching is easy, if you decide to go with one of the best green energy suppliers below. It can take less than a minute to get a quote  – simply provide your postcode, and a few details about the property you live in (like how many bedrooms there are). You can then refine your quote with more information, or decide to switch there and then. 

The best green energy supplier in the UK

The best green energy supplier in the UK right now is Bulb. This renewable energy company boasts strong green credentials: it supplies 100% green electricity and 10% green gas (the rest is offset, making it 100% carbon neutral ). It also has just one tariff, which keeps things simple. 

Plus, Bulb also gets consistently good reviews from customers. It's chalked up an impressive five stars on Trustpilot, from almost 25,000 reviews. And the icing on the cake? If you refer a friend, you'll both get £50.

The right green energy supplier for you will of course depend on your personal preferences and budget. Bear in mind, too, that just because you've signed up to a green energy supplier, there's no guarantee – and no way of ensuring – that what comes out of the National Grid into your home is actually green. However, the energy that goes back in to replace what you've used will be green. 

Whether you're looking for the greenest energy supplier, cheapest green energy supplier, best customer service or more, here's everything you need to know to make the switch to green energy.

The best green energy suppliers in the UK right now

best green energy supplier: Bulb

(Image credit: Bulb)

1. Bulb

The best green energy supplier in the UK – and if you refer a friend, you'll both get £50

Energy provider: Bulb
Green electricity: 100%
Green gas: 10%
Renewable sources: hydro (9%), solar (40%), wind (51%)
Carbon offsetting: Yes
Exit fee: None
Reasons to buy
+Only one tariff to choose from+10% green gas+£1 donated to charity when you switch
Reasons to avoid
-No fixed tariff, so prices can go up or down

We think Bulb is the best green energy supplier in the UK, with excellent green credentials, fair prices and first-class customer service. Launched in 2015, it’s the fastest-growing green energy provider in the country, now supplying over 1.4 million homes. 

That's in no small part down to its affordability: Bulb generally sits at the cheaper end of the UK energy market. The exact price you pay depends on where you live, as is the case with all energy companies. However, independent energy switching site Energy Helpline found Bulb to be on average 17% cheaper than standard deals from the Big Six.

Bulb buys its energy from independent generators, so it's able to guarantee its electricity is 100% green (it’s produced from hydropower, wind and solar). It also supplies 10% green gas – that's around average for a green energy supplier – which comes from renewable sources such as food and farm waste. Bulb then offsets the rest of the gas it supplies by supporting carbon reduction projects around the world, making its gas 100% carbon neutral. 

Happily, Bulb has just one tariff, which is simple to understand. It’s variable, which the company says makes pricing fair because any drops in the wholesale price of energy will be passed on to you. But like any variable tariff, bear in mind that prices can go up too. Finally, it’s worth noting that Bulb doesn’t charge an exit fee if you choose to switch energy provider. 

Bulb isn't the greenest energy supplier in the UK – that crown goes to Green Energy UK, below, which delivers 100 green gas. Bulb is cheaper than Green Energy YK, though. And it's beloved by customers, averaging an impressive 4.5 out of 5 stars on consumer review site Trustpilot, from almost 30,000 reviews. If that’s not enough, when you switch they’ll donate £1 to Edible Playgrounds by Trees for Cities. Plus, if you recommend a friend, you’ll both get £50. 

best green energy supplier: green energy UK

(Image credit: Green Energy UK)

2. Green Energy UK

The greenest energy supplier in the UK, and the only one to have 100% green gas

Energy provider: Green Energy UK
Green electricity: 100%
Green gas: 100%
Renewable sources: hydro, solar, wind,
Carbon offsetting: No
Exit fee: None
Reasons to buy
+100% green gas+100% green electricity
Reasons to avoid
-Expensive-Some concerning reviews online

Green Energy UK is the only supplier to offer 100% green gas as well as green electricity, making them the only true green energy supplier. You’ll have to pay more for these green credentials because they are exempt from the Ofgem price cap. In fact, they were 38% more expensive when we did a price comparison of all the suppliers mentioned in this guide.  Just make sure you do some research and check out their reviews online, as there are some concerning comments about billing.

Best green energy supplier: Outfox the Market

(Image credit: Outfox The Market)

3. Outfox The Market

The cheapest green energy supplier, but questionable customer service

Energy provider: Outfox the Market
Green electricity: 100%
Green gas: 0%
Renewable sources: wind
Carbon offsetting: No
Exit fee: None
Reasons to buy
+The cheapest in our price comparison+Live chat customer service+100% green electricity
Reasons to avoid
-Concerning reviews online

Outfox the Market is the cheapest green energy supplier available. They claim to pass on the best prices to customers with a no frills approach, but the number of negative reviews online is concerning (29% of Trust Pilot reviews are poor). Recently, Outfox the Market scrapped its old membership charge in favour of the typical standing charge like all the other suppliers. They may be the cheapest, but it’s worth noting that the best supplier, Bulb, is only 18% more expensive and is far more established with much better customer service.

Best green energy supplier: npower

(Image credit: npower)

4. npower

The best option for green energy from a Big Six provider

Energy provider: N Power
Green electricity: 100%
Green gas: n/a
Renewable sources: hydroelectricity and wind
Carbon offsetting: Yes
Exit fee: £30 per fuel
Reasons to buy
+100% green electricity+Plant a tree when you switch+Audited as green
Reasons to avoid
-Exit fees

npower is the best Big Six supplier for green energy because they offset carbon, plant a tree when you switch, and have been audited by EcoAct who certified that their Go Green Energy Fix meets their green standards. npower’s prices are firmly in the middle of the range, and if you pay by direct debit you’ll get a discount. Plus, they’re the only energy provider to have received triple certification from the Carbon Trust Standard, recognising their commitment to reduce carbon, water and waste from their offices. 

best green energy supplier: Ecotricity

(Image credit: Ecotricity)

5. Ecotricity

Ecotricity is the ethical choice. It's the only vegan green energy supplier

Energy provider: Ecotricity
Green electricity: 100%
Green gas: yes
Renewable sources: wind (98%), solar (0.12%) and hydro (0.7%)
Carbon offsetting: Yes
Exit fee: No
Reasons to buy
+Approved by the Vegan Society+Anti-fracking campaigners
Reasons to avoid
-Expensive-Poor reviews when switching away

Ecotricity is the only energy company in the UK to be recognised by the Vegan Society and get its stamp of approval, making it the only vegan energy choice. Their prices are expensive, but if you care more about ethical suppliers than cost, they might be the best choice for you. Ecotricity funds and supports anti-fracking campaigners in England, and has followed in the footsteps of Extinction Rebellion to declare a climate emergency. They also generate their own green gas, although you won’t get 100% green gas from them. Just beware the negative reviews around closing accounts and switching away from them on Trustpilot.

Best green energy supplier: OVO Energy

(Image credit: OVO Energy)

6. OVO Energy

The best green energy supplier for customer service

Energy provider: OVO
Green electricity: 100%
Green gas: 15%
Renewable sources: Anaerobic digestion 49%, solar 32%, wind 18%, hydro 1%
Carbon offsetting: Yes
Exit fee: £30 per fuel
Reasons to buy
+Award-winning customer service+Plant trees when you switch
Reasons to avoid
-Pay extra for green energy-Exit fees 

OVO is the best green energy supplier for customer service. As well as winning awards for customer satisfaction, 87% of their reviews on Trustpilot are rated good or excellent - which is very rare for an energy company. When you switch, they’ll plant five trees a year for you to offset your carbon emissions. They’ll also send you 100% green electricity and 15% green gas - but you’ll have to pay a fee, which is currently £5 per fuel, per month.

best green energy supplier: Co-op Energy

(Image credit: Co-op Energy)

7. Co-op Energy

The best green energy supplier for local energy

Energy provider: Co-op Energy
Green electricity: 100%
Green gas: 25%
Renewable sources: solar panels (45.61%), biodegradable (19.35%), landfill gas (13.32%), wind (10.67%), biomass (6.98%), biogas (3.63%), hydro (0.43%)
Carbon offsetting: Yes
Exit fee: no
Reasons to buy
+25% green gas+Supports community energy generation+Choose where your energy comes from
Reasons to avoid

Co-op Energy is the biggest backer of community energy projects in the UK, and gives its customers the chance to choose which project they buy your energy from. This helps to shorten the distance that energy has to travel and is helping more communities to generate their own power and improve their local economy. Co-op energy also produces a lot of low-carbon energy - but rely on nuclear power to do this, and still use some coal and gas stations. And they’re one of the more expensive suppliers on the market. 

Other green energy companies to consider

Interested in what else is out there? Here are a few more leading green energy companies in the UK that are looking to shake up the energy market.

Octopus Energy
Octopus Energy provides 100% green electricity by matching your usage and generating the same amount from renewable sources. It's one of the most transparent about where its energy comes from, and one of the cheapest green energy suppliers available. Get a quote from Octopus Energy now.
View Deal

Pure Planet
Pure Plant is a digital-only app-based green energy supplier that charges a membership instead of a standing fee. It doesn't mark-up its prices, making Pure Planet the second cheapest green energy supplier in this guide. It don’t use nuclear or coal, and offsets all of the carbon from its gas. Get a quote from Pure Planet now.View Deal

Green Network Energy
Green Network Energy offers 100% green electricity and 10% green gas. It doesn't generate the energy from renewable sources itself, but it matches your usage by buying green energy. And it has a whopping 4.5 stars on Trustpilot. Get a quote from Green Network Energy now.View Deal

Other energy suppliers with green tariffs 

If you're not convinced about switching to a smaller green energy supplier, here's our pick of the best bigger energy companies that also offer a good green tariff.

E.ON gives all its customers 100% green electricity, and its Fix Online v4 tariff is one of the cheapest around. The company is leading the way with generating green energy, and since 2017 has invested more than €9.5 billion in renewables – but E.ON didn’t take the top spot as best Big Six supplier here because it has a lot of negative reviews on Trustpilot. Get a quote from E.ON now

ScottishPower offers green energy for a monthly fee of £3 with its Go Green Bolt On. It sold its gas plants and closed its coal-fired power stations, further boosting its green credentials. And while ScottishPower ranks well in some customer polls, it’s got a poor profile on Trustpilot, so we haven’t recommended it as one of the best green energy suppliers. Get a quote from ScottishPower now

British Gas
British Gas gets 43% of its electricity from renewable sources, but its green tariffs will match 100% of the electricity you use with renewable electricity, and offset the carbon footprint of the gas. It has a number of green tariffs to choose from, depending on how long you want to fix the price for, or your energy use habits, but it's one of the more expensive green energy suppliers. Get a quote from British Gas now

What is green energy?

Green energy is simply electricity and gas that’s generated from renewable sources instead of fossil fuels like coal and gas. 'Green gas' refers to Biomethane, which is a naturally occurring gas produced from the breakdown of organic materials and landfill gas. Green electricity, meanwhile, is the electricity produced from renewable sources in the following ways: 

  • Wind power, where wind provides the mechanical energy to turn turbines
  • Solar power, where sunlight is absorbed by photovoltaic panels
  • Hydroelectric power, where fast-flowing water drives the turning of turbines 
  • Wave power, where the motion of waves drives tools like hydraulic pumps
  • Tidal power, where the rise and fall of the tide pushes turbines

Is green energy more expensive?

Green energy isn’t necessarily more expensive. The cheapest suppliers in our price comparison were Outfox the Market and Pure Planet, which are both green energy companies. That said, the most expensive in our price comparison – Ecotricity and Green Energy UK – are also green energy suppliers.

The price difference is usually down to just how green the energy really is. You’ll usually pay more for a supplier that generates its own electricity from renewable sources and provides some level of green gas, and pay less if the supplier simply matches your usage by buying green energy. 

Regardless of the supplier you choose, there are a few tips on how to keep your energy costs low:

  • Consider a fixed-price tariff. Your costs will be frozen so you’ll avoid any price hikes
  • Request a smart meter to keep an eye on your energy usage
  • Wash your clothes on a lower temperature
  • Turn off appliances when they’re not being used
  • Put your heating on a timer
  • Draught-proof your property
  • Shop around for energy quotes - but don't be swayed by price alone. Check fuel mix, customer service and reviews to get a fair picture.
  • Try a tool like Energy Monitor that will alert you when you could switch tariffs to save money.

How to choose the best green energy supplier

When you’re choosing a new green energy supplier you need to check their fuel mix and see if they can guarantee you’re getting green electricity – or if they’ll just offset your usage. You’ll need to decide which option is right for you.

You can find out what type of energy your supplier uses by looking at their fuel mix. Each year, energy companies must report to Ofgem exactly how their energy is generated, which gives us a fair way to see which suppliers are truly green and which still rely on coal, for example. 

You also need to think about the stability of the supplier. You may fear that a smaller company is less reliable – and the news that many have gone bust in the last 18 months won’t allay those fears – but it’s worth knowing that even if your provider goes bust, your supply won’t be interrupted, you’ll just be moved to a different supplier. 

It may well be worth the switch: the smaller suppliers tend to have better service and much happier customers, according to customer satisfaction polls. And some, like OVO, Octopus, and Bulb have become as well-known as the Big Six suppliers.