The company, which has 3.3 million households on its books, said it was responding to growing demand for greener electricity.
However, it was clear from the announcement that it remains some way off producing enough renewable energy of its own to meet its customers' needs.
E.ON said that around half of its output would come from its own estate of five offshore wind farms, 16 onshore sites and three biofuel facilities - with support from around 16 other independent sites via contracts.
It said the rest of the power would come from other sources - which can include the likes of natural gas and coal-fired power - but said they would be offset through the purchase of Renewable Energy Certificates.
Today, renewable energy resources like wind and solar power are so affordable that they’re driving coal production and coal-fired generation out of business. A recent survey by the trade publication Utility Dive found that electric power industry leaders expect significant growth in solar, wind, natural gas and energy storage.
AdvertisementThe certificates, the German-owned company said, guarantee that an equivalent amount of renewable electricity is generated to the amount supplied.
The industry is facing challenges on many fronts as demand for green electricity grows ahead of a future littered with targets to help battle climate change - with enough capacity to power an electric transport infrastructure.
Renewable Energy Is Becoming Popular. Over the course of its recent history, renewable energy has had a fight on its hands. Traditional forms of energy production like coal and oil have made it difficult for renewable energy to become as popular. That, however, is starting to change. By 2018, renewable energy will be around 25% of the world’s gross power generation. In other words, one quarter of the world’s energy output will come from renewable energy sources.
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Coal currently accounts for just 10% of total electricity output.
It is hoped offshore wind will provide a third of the country's electricity by 2030 - up from the current 7%.The government wants new nuclear plants to help fill some of the void but the private sector is running scared of investment, with two major projects falling apart in the past year leaving just Hinkley Point C in Somerset as the only scheme currently under construction.
Of the other big six suppliers, only ScottishPower has committed to a greener source of generation, through wind only.
prices for oil and natural gas, and a number of state and federal government incentives, including the Energy
It sold its last gas-fired power assets to Drax in 2018 and has since pledged a £2bn investment in renewables.E.ON UK chief executive, Michael Lewis, said: "Climate change is the defining issue of our era, and one that energy customers are increasingly concerned about."We believe large-scale action can make significant change possible and we're committed to playing a leading role and setting an example for others to follow, that's why we're providing all of our residential customers with 100% renewableelectricity as standard - a change at a scale never seen before in Britain."
Energy expert at the switching site uSwitch.com, Rik Smith, said: "Today's announcement applies to all E.ON customers, including those on poor value standard tariffs.
"But green energy deals now compete on price with their more carbon-intensive counterparts, so those households who are on a standard deal should shop around to see how much they could save by switching.
"The cheapest green plan on the market costs less than £900 a year, a whole £380 cheaper than E.On's standard plan."