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Renewable energy what are the costs?

Many energy companies now offer green tariffs, which usually take one of two forms; a green power supply or a green fund. If you choose a green power supply then for every unit of electricity you use, an identical amount of green energy is produced. On the other hand, a green fund costs you extra each month, but the energy company then invests this into renewable energy projects. Some companies offer nothing but green energy tariffs, such as Ecotricity, Good Energy and Green Energy UK. Also, many of the “big 6” energy providers offer green tariffs if you are prepared to pay a premium on bills.

With so many green electricity tariffs on the market, it can be hard for consumers to distinguish between the genuinely green and the “greenish”. One important measure of “greenness” is the fuel mix disclosure, as it demonstrates an energy supplier’s commitment to renewables. All suppliers are required to provide information about the mix of fuels used to generate the electricity supplied to their customers, as well as its environmental impact. Known as the Fuel Mix Disclosure, suppliers must publish this information annually and notify their customers. The average proportion of renewable electricity supplied in the UK is 7.9% (2010-2011), with some providers supplying more or less.

The table below provides the fuel mix disclosures for a variety of energy suppliers, including the big 6 and specialist green energy suppliers, in order of the percentage renewable.

Fuel Mix Disclosure Data of various suppliers

Supplier Coal % Natural Gas % Nuclear % Renewable %  Other % Disclosure Year
 Good Energy  0.0  0.0  0.0  100.0  0.0   2015
Ecotricity  0.0  0.0  0.0  100.0  0.0   2015
Hudson Energy  0.08 0.08 0.07 99.8 0.02   2015
Opus Energy  4.0 3.0 2.0 90.0 1.0   2015
Smartest Energy  20.6 19.3 7.6 49.1 3.4   2015
Total Gas & Power  22.0 21.0 8.0 45.0 4.0   2015
Green Energy UK  0.0 57.0 0.0 43.0 0.0   2015
Gazprom  23.3 21.8 8.6 42.5 3.8   2015
LoCO2 Energy  0.0 60.0 0.0 40.0 0.0   2015
Engie 23.9  36.5 0.8 38.4 0.4   2015
SSE 31.0  27.0 3.0 37.0 2.0   2015
Haven Power  28.0 26.0 10.0 30.0 5.0   2015
Dong Energy  31.2 29.2 11.4 23.2 5.1 2015
British Gas  11.0 33.0 2.3 20.0 1.0 2015
Scottish Power 46.4 30.3 2.3 20.0 1.0 2015
Dual Energy  26.7 29.7 22.2 19.3 2.1 2015
npower/RWE  21.0 59.0 2.0 17.0 1.0 2015
e.on  33.9  31.7 12.4 16.5 5.5 2015
EDF Energy  22.6 6.1 54.9 16.3 0.1 2015
Corona Energy  38.7 36.2 14.2 4.6 6.3 2015
First:Utility  38.7 36.2 14.2 4.6 6.3 2015
UK Average 26.7 29.7 22.2 19.3 2.1 2015


Using this information from the Fuel Mix Disclosure, and from independent research carried out by Powerful Allies, it is possible to draw up a table in which the main suppliers are subjectively rated on their ability to produce green power. In addition, this table provides a summary of some of the green tariffs available, and what the providers are doing to help consumers be greener within their business. This can be seen in the table below.

Efficiency of electricity generation

Suppliers Fuel Mix (% Renewable) Further Information Green Rating (High, Medium, Low)
 Good Energy  100.0% Projected 2015/16 fuel mix: 54% wind, 21% solar, 4% hydro, 21% biogen.
Electricity comes from growing community of independent suppliers, also developing their own wind farms (2 operational, 2 planned) and solar farms (7 operational, 6 planned).
 Ecotricity 100.0%  Sun parks: 1 operating, 1 building, 4 planning.
Wind parks: 23 operating, 4 building, 7 planning.
Sea: developing Searaser sea mills, collaborated on Snapper electrical generator.
Gas: planning green gas mills, green gas they supply comes with shale Frack Free Promise.
Business tariffs:
•    Small business tariff: 100% green (35% from their own windmills)
•    Large business tariff: 100% green (40% from their own windmills)
Can provide on-site wind energy by building turbines.
 Hudson Energy  99.8%  Around 50% of their renewable electricity is from hydroelectric generators, 40% from wind.
Offer 2 renewable tariffs:
•    100% Renewable
•    100%+ Renewable, where you can choose the source of your electricity (wind, solar or hydro)
 Opus Energy 90.0% Energy sources: 45% hydro, 37.5% wind, 16.9% biomass & landfill, 0.6% photovoltaic (PV/solar).
Energy sources: 85.95% Scandinavia, 3.9% England, 0.8% Scotland, 0.2% Wales, 9.2% other (Europe).
Between April 2013 and March 2015, 90% of energy supplied came from renewable generators.
Offer tariffs that are 100% renewable or part renewable.
 Smartest Energy  49.1%  Portfolio of over 600 generation projects including wind, hydro, wave & tidal, biomass, landfill gas, energy from waste, solar and battery storage.
Offer 3 renewable tariffs:
•    Standard: from a blend of sources
•    Natural: from wind, sun or water
•    Specific: allows you to choose your preferred source
All renewable products are certificate-backed, and are developed with support from the Carbon Trust.
 Total Gas & Power  45.0%  Offer power generated from renewable sources (wind, biomass and hydro) and low carbon CHP, compatible with all electricity products on offer for no extra premium.
Offer an Eco-Energy tariff for small/medium businesses which is 100% renewable.
 Green Energy UK  43.0%  Fuel mix: 57% CHP, 17% anaerobic digestion, 16% energy from waste, 4% wind, 4% solar, 1% biomass, 1% hydro.
•    Tap and Still tariffs: use CHP
•    Sparkling tariff: energy is 100% sustainable, no CO2 emissions
Also offer gas that is 100% green.
Gazprom 42.5% 7 year deal to purchase hydroelectric power from 10 sites across UK.
15 year deal to purchase electricity from up to 40MW of solar farms in the UK.
Previously had deals to purchase landfill gas.
Offer Levy Exempt Backed (LEB) energy from 100% renewable sources.
Can choose gas which is all or partly carbon neutral.
Can buy carbon offset certificates to offset carbon footprints.
Have a variety of carbon trading options.
LoCO2 Energy 40.0% Renewable energy comes from 31% AD, 29% hydro, 27% wind, 13% solar PV
Network of 9 hydropower stations, one more under construction, plans to build more.
2 business tariffs:
•    Business Planet: 100% renewable energy predominantly from their own hydropower sites
•    Business Pocket: Low-carbon tariff, minimum of 50% renewable but increasing all the time
Engie 38.4% The group has a photovoltaic power generating capacity of 201MW across 15 countries.
They also have 3,668MW of onshore wind power installed around the world, and are investing in offshore wind power projects in Europe.
Have carried out a number of biomass research projects, and have over 50 sites generating electricity from biomass.
SSE 37.0% Largest generator of electricity from renewable sources across UK and Ireland.
Have 3,275MW of renewable capacity in total, 2,731MW of this in Great Britain.
1,008MW of wind farms in operation in Great Britain, with more in construction.
1,150MW hydro electricity across 50 hydroelectric power stations, 300MW from pumped storage facility.
Also have 37MW of dedicated biomass.
Haven Power 30.0% Parent company Drax is the single largest renewable energy generator in the UK.
Drax is becoming a predominantly biomass-fuelled generator, converting some of its existing generation units to use compressed wood pellets instead of coal.
Offer a biomass renewable energy option with all of their products.
Dong Energy 23.2% World’s largest generator of offshore wind, with 3GW in operation around Europe and 3.3GW under construction.
Operate 6 offshore wind farms in the UK, with more in construction.
Offer renewable energy contracts at no additional cost, which can be integrated into any of their contracts.
Offer contracts with 100% offshore wind power from their own UK wind farms.
British Gas 23.0% Government-approved installers under the Microgeneration Certification Scheme (MCS) and are members of the Renewable Energy Assurance Listed (REAL) assurance scheme.
Have 17 years’ experience in solar innovation.
Centrica has sold its entire wind power portfolio.
Offer energy sourced from offshore & onshore wind, solar, biomass, landfill gas, hydro and wave power.
Scottish Power 20.0% Part of the Iberdrola Group, a world leader in wind energy production with a renewables capacity of over 24,900MW.
Scottish Power has 30 operational windfarm sites producing over 1600MW, further 500MW planned.
Developing projects to harness wave energy.
Leading the industry in development of tidal energy.
Dual Energy 19.3% No further green information. L
npower/RWE 17.0% RWE Innogy UK operates 22 hydroelectric power schemes, 28 onshore and 2 offshore wind farms.
Currently installing its first biomass CHP power plant in Scotland.
Can help companies set up renewable energy projects.
Offer REGO-backed renewable energy as an option in its fixed and flexible contracts.
e.on 16.5% 2nd largest offshore wind operator in the world, 8th largest company in onshore wind.
Partners in the world’s largest offshore wind farm.
Have 16 operational onshore and 5 operational offshore wind farms in the UK.
Have two dedicated biomass power stations, including one of the UK’s largest.
Market leader in the large-scale CHP market.
Can install onsite renewable microgeneration technologies.
Offer REGO-backed renewable energy option in its Fixed, Multipurchase and Flexible products, for both HH and NHH customers.
EDF Energy 16.3% 31 operational wind farms, 4 under construction, 4 proposed.
They offer to advise, design, install and manage renewable energy generation systems for businesses.
Offer a Renewable for Business tariff.
Corona Energy 4.6% No further green information. L
First:Utility 4.6% No further green information. L

Thus, using this information as well, an energy scale bar has been drawn up, making comparisons between the five major sources of green energy and fossil fuels. From this data, it is clearly visible which energy generation methods should be invested in, and use of them should be encouraged. This colourfully and simply shows the various types of energy, and enables consumers to work out how green their energy actually is. This is below: