What is renewable energy, what forms do we use in the UK and what does the future of renewable energy look like?

What does ‘renewable energy’ mean?

The word ‘renewable’ means something that comes from a source that won’t run out.

When we talk about energy, we refer to electricity, heating and fuels used for transport.

So renewable energy is energy from a naturally occurring source that will never run out; that is used to generate power or heat or to propel a vehicle.

A solar panel farm

What renewable energy sources do we use in the UK?

In the UK we generate renewable electricity from four main sources: Solar, wind, hydro and bioenergy.

Solar energy is used to generate electricity or heat water using solar panels. There is 14.6GW of installed solar in the UK, ranging from huge solar farms to a solar panels on household rooftops. Find out more about how solar panels work here.

Wind energy is captured from wind turning the blades of wind turbines which are located on land (on shore) and at sea (off-shore). In 2020, around 24% of the UK’s electricity was generated from wind power – and this number is growing every year. Find out more about wind turbines here.

Hydro power is created from the movement of flowing or falling water turning a turbine. In the UK hydro energy makes up around 2% of our electricity mix, but globally it is the third largest source of electricity after coal and gas. Find out more about hydro energy here.

Bioenergy refers to electricity, gas and biofuels that are generated from organic matter, known as biomass. This can be anything from plants and timber to agricultural and food waste – and even sewage. Find out more about how we turn matter into energy here.

A hydro turbine set in flower fields

What other renewable energy sources are used?

Around the world, other renewable sources are also harnessed to generate energy:

Geothermal energy is heat that comes from the sub-surface of the earth. In Iceland, for example, naturally-heated geothermal water is pumped into 90% of the homes to provide hot water and heating. It is also used to generate electricity, with turbines turned by released steam. Read more about how the Eden project are planning to harness geothermal power in the UK too.    

Tidal power uses the movement of sea tides to turn turbines and generate electricity. Challenges including huge upfront cost, habitat change and maintenance complexities have meant that there are currently very few tidal power stations around the world.

What forms of renewable heating are there?

There are also a few renewable heating sources that we use in the UK.

Heat pumps capture heat from the outside, either from the air or the ground, and move it inside. They use electricity to work, but they generate much more heat energy than the electricity used to power the system. Find out more about our heat pump service here.

Solar thermal panels collect the heat from the sun and use it to heat up water. These are often used alongside other heating systems as the available solar energy varies throughout the year.

Biomass heating systems burn wood pellets or logs to heat spaces and sometimes heat water. They are considered sustainable as long as new plants grow to replace those used for fuel.

Heat pump outside house

Why are fossil fuels not renewable? 

Fossil fuels – oil, gas and coal, were formed millions of years ago from decomposing prehistoric plants and animals put under extreme pressure and heat. It’s taken millions of years for these fuels to form, so it isn’t an option to wait for more.

We’ve been using fossil fuels for just over 200 years, and it is estimated that we will run out of all known supplies this century. As well as being a limited resource, the burning of fossil fuels for energy is the biggest contributor to our dangerously heating planet.

What does the future of energy look like?

We must stop using fossil fuels to avoid the worst impacts of climate change; and also to enjoy the security of cheaper, far more stable energy bills.

In the UK, we’ve committed to targeting ‘net zero’ by 2050 – but what could that look like?

Low carbon generation: We will need to generate all of the UK’s electricity from low or zero carbon sources. And we need to find affordable ways to store that energy to use at peak times, like cold winter evenings when we all make dinner and put on our heating at the same time. In 2021, renewables made up 38.7% of our electricity mix.  

More home-grown energy: More and more houses and businesses will install rooftop solar panels (or other renewable technologies) and batteries, so we can use what we generate at home and get paid for what we don’t use.

Electrified transport and heating: New petrol and diesel cars will be banned from 2030. And after 2025, gas boilers won’t be installed in new homes either; with heat pumps used instead. Gradually we will need to electrify all forms of heating and transport to eliminate these two huge fossil fuel consumers.

Efficient energy: We must use a lot less energy in the first place – with all houses and businesses being properly insulated to avoid losing heat. We’ll need to switch out old inefficient equipment and appliances, and change our habits about how we use energy too (for example, by programming washing to be done overnight).

See our vision of a future based on renewable energy here: