Understanding your electricity: our fuel mix

A process by which a fuel, such as waste crops or other organic matter, is decomposed by bacteria in the absence of oxygen. This produces a biogas which can be used to generate energy.

Anaerobic digestion is a source of renewable electricity and produces no Scope 2 carbon emissions. It is included in the fuel mix of our Renewable Standard product and can be included in Specific Renewable at customer request.

Organic matter such as wood chips, pellets, grass etc is combusted and the resulting heat is converted to energy. It is considered sustainable because the carbon released in the combustion process is offset by the carbon trapped in the organic matter by photosynthesis during its growth.

Biomass is a source of renewable electricity and produces no Scope 2 carbon emissions. It is included in the fuel mix of our Renewable Standard product and can be included in Specific Renewable at customer request.

The process of generating electricity by harnessing the power of water. Hydroelectric power is produced by guiding water flow through a turbine to create the momentum required to drive an electric generator and includes:

• Storage – where a dam collects water in a reservoir, then releases it to drive turbines, producing electricity
• Run-of-river – where the natural flow of a river or stream is used to drive a turbine
• Marine energy - where energy is generated from the kinetic energy of waves, from underwater currents, or from the changing of the tide

Hydro is a source of renewable electricity and produces no Scope 2 carbon emissions. It is included in the fuel mix of our Renewable Standard and Natural Renewable products and can be included in Specific Renewable at customer request.

Solar PV is designed to supply usable solar power by means of photovoltaics (converting solar into electricity). It utilises solar panels to absorb and convert sunlight into electricity (with a number of other components). PV systems can be small, roof-top mounted or building-integrated systems with capacities from a few kilowatts to hundreds of megawatts.

Solar PV is a source of renewable electricity and produces no Scope 2 carbon emissions. It is included in the fuel mix of our Renewable Standard and Natural Renewable products and can be included in Specific Renewable at customer request.

Refers to electricity generated from a Combined Heat and Power (CHP) unit which is fuelled by a renewable fuel source such as biomass, biogas generated by anaerobic digestion or waste.

Thermal is a source of renewable electricity and produces no Scope 2 carbon emissions. It is included in the fuel mix of our Renewable Standard product and can be included in Specific Renewable at customer request.

Energy from waste is the process of generating energy from the primary treatment of waste products. Technologies for generating power include combustion, which involves burning the waste and recovering electricity or heat (eg. municipal and industrial waste), and gasification, which involves fuel being heated with little or no oxygen to produce “syngas” which can be used to generate energy (eg. landfill gas).

Waste is a source of renewable electricity and produces no Scope 2 carbon emissions. It is included in the fuel mix of our Renewable Standard product and can be included in Specific Renewable at customer request.

This refers to wind turbines that convert the wind’s kinetic energy into electrical energy. Wind turbines consist of blades which rotate around a horizontal hub connected to a gearbox and generator. The generator uses magnetic fields, converting this rotational energy into electricity. Wind energy can be produced offshore (where wind turbines harness the energy from air moving over the oceans) and onshore (where wind turbines are anchored to land).

Wind is a source of renewable electricity and produces no Scope 2 carbon emissions. It is included in the fuel mix of our Renewable Standard and Natural Renewable products and can be included in Specific Renewable at customer request.

This represents the portion of the UK grid mix which is from renewable sources. This data, provided by Ofgem, is not split by generation technology but would include a mix of all renewable sources.

Grid renewables will only be found in our Conventional fuel mix because it forms part of the UK residual grid mix.

A fossil fuel made up of combustible substances that gives off carbon dioxide when burned. A coal power station grinds and then burns coal in order to create electrical energy. Coal releases harmful gases into the environment when used to create energy so it is being phased out across the world in favour of renewable sources of electricity.

Coal is a source of non-renewable, conventional electricity. It can be found in our Conventional fuel mix because it forms part of the UK residual grid mix.

Natural gas is a fossil fuel typically found in deep underground rock formations, created by layers of organic matter being exposed to intense heat and pressure over hundreds of millions of years. In a type of internal combustion engine, the burning of an air-fuel mixture produces hot gases that spin a turbine to produce power.

Natural gas is a source of non-renewable, conventional electricity. It can be found in our Conventional fuel mix because it forms part of the UK residual grid mix.

Nuclear power makes use of nuclear reactions using uranium which releases nuclear energy to generate heat. This is usually then used in steam turbines to produce electricity in a nuclear power station.

Nuclear is a low-carbon source of electricity because it does not create carbon emissions when generating but it is not renewable because it relies on uranium and produces radioactive waste.

Nuclear can be found in our Conventional fuel mix because it forms part of the UK residual grid mix.

Other fuels includes non-biodegradable wastes, oil, coke oven gas, blast furnace gas, and waste products from chemical processes.

Other non-renewables can be found in our Conventional fuel mix because it forms part of the UK residual grid mix.