It's important to know exactly how your electricity is generated so you can confidently report your carbon emissions and share your sustainability achievements. As well as the basic fuel mix we're required to report, we publish a detailed fuel mix for each product so you know the breakdown of your supply.

Every megawatt hour we supply to customers on our renewable products is from renewable generation and backed with an origin certificate. The fuel mix for these products from April 2023 to March 2024 is shown below, as well as our residual conventional mix and total overall fuel mix.

We've also included definitions of the renewable generation technologies in our supply so you can understand where your electricity comes from. To find out more about some of the independent generators we purchase power from, visit our case studies section here.

Renewable Natural Product Fuel Mix

Our Renewable Natural product is for businesses that want to embrace the forces of nature - the sun, wind and water - for their power. The fuel mix for Renewable Natural for the reporting period 2023/24 was:

(Solar PV – 54.77%, Wind – 40.00%, Hydro – 5.23%)

Scope 2 emissions: 0 gCO2/kWh
Total radioactive waste: 0 g/kWh

Renewable Standard Product Fuel Mix

Our Renewable Standard supply product provides electricity from a blend of renewable sources and, like all our renewable electricity, is backed by origin certificates. The fuel mix for our Renewable Standard product for the reporting period 2023/24 was:

(Waste - 58.45%, Biomass - 28.19%, Solar PV - 12.10%, Anaerobic Digestion - 1.26%)

Scope 2 emissions: 0 gCO2/kWh
 Total radioactive waste: 0 g/kWh

Renewable Specific Product Fuel Mix

Our Renewable Specific product enables supply customers to specify their bespoke renewable requirements for their generation source. The fuel mix for our Renewable Specific product for the reporting period 2023/24 was:

(Wind - 37.40%, Solar PV - 31.43%, Biomass - 26.70%, Waste - 2.46%, Hydro - 2.00%)

Scope 2 emissions: 0 gCO2/kWh
 Total radioactive waste: 0 g/kWh

Conventional Fuel Mix 

Once we have allocated all our renewable supply across the products above, what remains is the residual fuel mix for our Conventional customers, which is predominantly from grid sources. Our Conventional fuel mix for 2023/24 was:

(Natural gas - 67.29%, Coal - 14.57%, Nuclear - 10.50%, Other non-renewable - 6.54%, Waste - 0.90%, Other Renewables - 0.20%​)

Scope 2 emissions: 462 gCO2/kWh
Total radioactive waste: 0 g/kWh

 

SmartestEnergy's Total Fuel Mix

The total fuel mix for our overall supply across all products for 2023/24 was:

(Natural gas - 25.38%, Waste - 20.64%, Solar PV - 18.09%, Biomass - 11.21%, Wind - 10.97%, Coal - 5.49%, Nuclear - 3.96%, Other non-renewable - 2.47%, Hydro - 1.27%, Anaerobic digestion - 0.43%, Other Renewables - 0.07%)

Scope 2 emissions: 174 gCO2/kWh
Total radioactive waste: 0 g/kWh

 

If you have any questions about our fuel mix or would like to find out more about our renewable products, please get in touch here.

Environmental impact of fuel mixes energy sources
All energy sources have some impact on the environment, but to varying degrees. As the net zero transition and the shift to natural renewable energy sources (wind, hydropower and solar) convey – there’s a need to move away from fossil fuels (e.g. coal, oil and natural gas), which do substantially more harm than renewable sources.

So what are the kinds of environmental impact energy sources can have?
Impacts are far ranging and can include air and water pollution, damage to public health, wildlife and habitat loss, water use, land use, and global warming emissions. The intensity of the impact, as well as the type of impact, depends on the specific technology used, the location of the energy assets , and a number of other factors.

Our generation sources

See below for definitions of the renewable generation technologies included in our supply. Where renewable electricity has been provided, it additionally meets the criteria of Renewable Source Electricity as per the Finance Act 2000.

  • Anaerobic digestion

    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.

  • Biomass

    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.

  • Hydro

    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 Photovoltaic (PV)

    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.

  • Thermal

    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.

  • Waste

    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.

  • Wind

    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.

  • Grid renewables

    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.

  • Coal

    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

    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

    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 non-renewable fuels

    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.

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