Energy > Guides

Choosing a green energy tariff – what you need to know

Fred Isaac

Fred Isaac
Sep 13, 2017

If you’re an eco-conscious energy consumer in the UK, you’re spoilt for choice.

A raft of suppliers, including Ovo Energy, Ecotricity LoCO2, and Bulb Energy, have made green energy central to their businesses.

But choosing a renewable energy provider can be tricky.

How can you tell if a supplier’s green promises are just hot air? And does saving the planet have to cost the earth?


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If you’re thinking of switching to a renewable energy plan, make sure you read our guide before comparing deals online.  


What exactly is a ‘green’ energy tariff?

Strictly speaking, for an energy plan to be labelled “green” it must get 100% of its electricity from renewable sources, including wind farms, tidal power and solar panels. 

Plenty of green deals will also include a portion of renewable gas, typically about 10%.

Bulb Energy, for example, gets 10% of its gas from biomethane – the gas produced from organic matter or sewage.

Taking out a green tariff means that some or all the electricity you buy is ‘matched’ by orders of renewable power your supplier makes on your behalf.

So, for example, you may find a supplier that offers you fossil fuel generated energy, but that then matches it with a unit of 100% renewable energy, which is added to the National Grid.

Or, you could sign up to a tariff where the supplier contributes to a clean energy project.

Because all the electricity, no matter how it is produced, comes out of the mains, there’s no way to ensure the green energy you pay for is the stuff you use when you turn the lights on at home.

Instead, your purchasing decision means more energy from renewable sources will be added into the country’s overall mix.

So the more people that sign up to a green tariff, the bigger the percentage of green energy in the national supply. 

Last year Ofgem lifted the cap on the number of tariffs a supplier could offer, so keep an eye out for the Big Six reintroducing green offers.


How do you find out how green a supplier is?

Under Ofgem’s Renewable Obligation, suppliers are required by law to provide at least 15% of their energy from renewable sources.

But if you’re in the market to switch, how do you know just how green a provider is?

Every year, suppliers must publish their fuel mix disclosures, showing where it gets its fuel from.

A company’s fuel mix can be found on its website.

Google [Supplier’s name] Fuel Mix Disclosure and have a look what percentage of its energy comes from coal, gas, nuclear and renewables.

You can then compare it against the national average.

We’ve reviewed scores of energy companies and, as well as price and service, have assessed their green credentials.

To find what we thought, head to our Reviews Page and look up the supplier you’re interested in.


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Is green energy going to cost me extra?

In a nutshell, a green energy tariff is likely to cost you a bit extra because producing renewable energy costs more.

Offsetting carbon emissions and supporting environmental or social projects, such as schools or community centres, all eat into a supplier’s profit margins.

As its costs go up, so do yours.

If you’re switching from one of the Big Six’s standard variable tariffs (which millions of households are stuck on), however, you’ll probably save money – and the planet – wherever you go.

Realistically, though, to get a reasonably priced green deal you’re going to have to go with one of the smaller suppliers.

Smaller outfits with lower overheads are able to offer competitively priced green tariffs.

Even if a green tariff is a bit dearer, this may be a price you’re willing to pay to do your bit for the environment.

The only way you can find out if choosing a green tariff will cost you more is by crunching the numbers and comparing deals online.


Is my green tariff as renewable as it claims to be?

The jury’s out on whether buying energy from a green tariff necessarily means your electricity is 100% renewable.

All the electricity generate is connected to the grid, same as the non-renewable power.

When we turn the lights on, the electricity all comes from the same pool.

Because the carbon content of the mains electricity is worked out on this basis, it’s not possible for you to claim you are using carbon free electricity.

The exact offering of a green tariff can vary, so the bottom line is: check the T&Cs and speak to the supplier first to make sure you know what you’re paying for.

Then, when you've made your mind up, run a comparison and see what deals are available. 


What other ways are there to be a green energy consumer?

The biggest DIY, eco-friendly action is, of course, to use less energy.

Conserving gas and electricity also has the added benefit of knocking money off your bills.

Steps you can take include: 

* Double-glazing
* Boiler efficency
* Turning off appliances when not in use

For the full list, visit our guide on how to save money on your energy bills.

Plenty of suppliers now invest heavily in environmental and social projects, from planting trees to promoting renewable power in the developing world.

Ecotricity, for example, pioneers new green technology, including a sustainability-based mobile network called ecotalk.

Head back to our Reviews Page to find out what the supplier you’re keen on is doing.


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