Buying green electricity

Most of of the UK's electricity comes from burning fossil fuels (such as coal, oil and gas) which is a major contributor to climate change. Read more about green alternatives on this page.

Carbon-free electricity 

In 2014, carbon-free sources of electricity, including nuclear and renewables, accounted for almost 40% of total electricity production in the UK.

The proportion of renewable electricity being used is growing steadily. This increase is due to policies such as the Renewables Obligation, Contracts for Difference (find details of these at Ofgem) and the Feed-In Tariff. The UK Government wants at least 30 per cent of our electricity to come from renewable sources by 2020.

Green electricity offerings

Most energy suppliers offer 'green' electricity tariffs. These seek to support renewable energy. The two main types of offering are green supply tariffs and green funds.

Green supply tariffs

A green supply tariff means that some or all of the electricity you buy is 'matched' by purchases of renewable energy that your energy supplier makes on your behalf. These could come from a variety of renewable energy sources such as wind farms and hydroelectric power stations. Some green supply tariffs are also nuclear-free. Your supplier should let you know what sources are included in the mix, and also what proportion of your supply is renewable.

Many green tariffs state that your supply is 100% renewable. Some companies buy a mix of renewable and non-renewable electricity, but make sure that the amount of renewable electricity they buy is at least as much as the amount they are selling to customers through their green tariff. A few companies only buy renewable electricity, and so all their customers are on a green tariff. In either case, all the renewable electricity produced is supported by Government schemes that require electricity suppliers to buy some renewable electricity, and so it is difficult to say how much extra renewable electricity is produced as a result of signing up to a green tariff, even if it is with a 100% renewable supplier.

Green funds

A green fund usually involves paying a premium to contribute to a fund that will be used to support new renewable energy developments. Under this option, the existing electricity supply continues as normal, but your involvement could help to alter the mix of energy sources in the future toward renewable sources (depending on the type of tariff).

The new generation projects supported may also receive support under existing government support schemes.

How green are green tariffs?

  • There is a lot of debate around whether buying electricity from a green tariff means that your electricity is 100% renewable. All renewable electricity generated is connected to the grid, along with all the non-renewable generation, and we all draw electricity from that same pool. The carbon content of mains electricity is calculated on this basis, so it is not possible for one user to claim they are using carbon free electricity based on their electricity supplier.

    Carbon dioxide emissions are a global problem, so ultimately what matters is that total emissions are reduced. Opting for a green tariff can provide additional incentives for new renewable generation or energy efficiency measures, and so lead to some additional carbon dioxide savings in the long term.

  • Green tariffs are no substitute for energy efficiency and you should always do whatever you reasonably can to reduce your current use of electricity and other fuels before considering spending money on a green tariff.

The Energy Saving Trust does not recommend specific suppliers of green tariffs.