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The straightforward guide to green energy

More and more energy suppliers are offering renewable energy tariffs and deals but with terms like carbon offsetting, greenwashing and REGO’s it’s a complicated marketplace. Working out exactly what suppliers are providing can lead to confusion and sometimes a reluctance to switch in case you choose the wrong deal.

What is Renewable energy?

Renewable energy is often referred to as green or clean energy. It comes from natural, sustainable sources such as sunlight, wind and water. The four main types of renewal energy include:

  • Wind – onshore and offshore wind power
  • Water – hydro power, wave power and tidal energy
  • Solar energy – heat from the sun
  • Biomass – organic material that comes from plants and animals

However, the term ‘green energy’ can at times be misleading as not all ‘green’ energy is 100% truly green. Research undertaken by British Gas suggests that many people believe when you switch to a green energy tariff, you receive pure green energy from a separate ‘green’ network. This isn’t the case. With the exception of installations such as private solar panels on buildings, all the electricity generated by various generators around the UK goes to the National Grid and local distribution networks.

A renewable energy supplier matches the amount of electricity their customers use with the amount they buy from renewable sources. So, the more people that choose to go green, the more renewable energy there is in the Grid.

100% green?

Many energy suppliers promote green energy tariffs but it’s worth taking a closer look to see if they buy or generate their energy directly from renewable generators or if they buy a mix of green and fossil fuel generated energy and then match that with Renewable Energy Guarantee of Origin (OREGO) certificates. This means renewable energy is not being put back into the grid and does less to achieve a low-carbon economy.

 What are REGO’s?

REGO’s (Renewable Energy Guarantees of Origin) are certificates issued by Ofgem – the government department of Gas and Electricity markets – to accredited renewable generators to provide evidence that the energy they supply is 100% green. Your renewable energy provider buys green electricity and the accompanying certificates directly from UK wind, hydro or solar farms. This benefits the renewable energy industry and ensures complete transparency about the source of your provider’s energy supply.


When suppliers market their energy as ‘green’ in contradiction to their environmental practice or from where they buy their energy from, it’s called greenwashing. Some electricity suppliers, including some who claim to supply 100% renewable energy, will do so simply by buying REGO certificates from other suppliers. They then match the electricity they supply with REGO’s and claim their energy supply is renewable. However, by doing this they are not contributing to the UK’s supply of green energy or supporting true renewable energy generators.

 What’s Carbon Offsetting?

Where providers choose not to source100% green energy they can choose to offset any carbon emissions associated with the energy they provide by partnering with, or supporting, carbon reduction projects such as tree planting. Companies like Ecologi guarantee to invest your money into projects that remove more greenhouse gasses than your carbon footprint puts in.