Written by Josh Jackman Updated on 27 October 2022 ✔ It would take just eight years to create an entirely green energy mix✔ The initiative would cost £1.23 trillion✔ That’s only 4.4% of our GDPFor the sake of the climate and your energy bills, it’s vital that the government ensures we reach 100% green energy as soon as possible.Renewables are the cheapest way to produce the necessary energy, and the only way to reduce the ongoing climate catastrophe.Thankfully, our research shows the UK could run on completely green energy by 2030.All we need is the government to invest enough time, money, and effort into creating the necessary infrastructure. It may feel like a Herculean feat, but it’s completely feasible.In this guide, we’ll explain what the government needs to do, how much it’ll cost, and the associated challenges. What’s on this page? 01 How green is the UK’s energy right now? 02 When could the UK’s energy be 100% green? 03 What actions does the government need to take? 04 How much would it cost to go 100% green? How green is the UK’s energy right now?13.1% of energy consumed in the UK each year is green, according to government data.Bioenergy and heat supplies 5.5%, and the remaining 7.6% comes from green electricity that’s powered by renewable sources like hydropower, solar, and wind.40% of the electricity we consume is green, but unfortunately, electricity only supplies 19% of the energy we use at the moment.All of this adds up to 195 TWh of green energy per year – well short of the 1,492 TWh that the UK requires each year. When could the UK’s energy be 100% green?The UK's energy could be 100% green by the end of 2030.That’s how long it would take to build enough hydropower, solar, and wind farms to replace the 1,297 TWh of non-renewable energy the UK uses.We’re also confident that in this timeframe, the public and companies could be provided with the technology they’ll need to use this green energy to heat and light their buildings, and to transport themselves.See what we think a fully 100% renewable UK might look like. What actions does the government need to take?The government needs to increase green energy generation by 665% to meet the country’s consumption demands with just renewables.Then we need to make sure the UK’s 28.1 million households have the technology they’ll need to use this green energy, partly by stopping high costs from preventing people from getting on board.Here’s how it could be done.Produce enough green energyTo reach the magic 1,297 TWh figure, we should massively ramp up the amount of hydropower, solar power, and wind power we generate.Geothermal is impractical at the moment, with each 500 MW power plant costing around £2.5 billion to build – which is between three and six times more expensive, per MW, than the other options.We’re not relying on nuclear power either. It’s a low-carbon alternative, but it’s not green, and it’s certainly not renewable.Onshore windTime neededEnergy generatedNumber of sitesCost8 years411 TWh4,000£250 billionWe’ll need to increase onshore wind energy 14-fold – but this kind of wind revolution is well overdue.Prime Minister Rishi Sunak’s government has u-turned on Liz Truss’s decision to relax rules around onshore wind farm construction, meaning the six-year-long ban on most installations will continue.Instead of this atrocious anti-growth move, the government should slash the time it takes to approve wind farm constructions.To build an onshore wind farm, it currently takes 5.4 years on average, from submitting your plans to getting the turbines up and running.But it doesn’t need to.You generally need around six months to physically build a 50 MW onshore wind farm – and if the government could reduce its own bureaucracy and delays, the total time it takes could come down to a year.If the industry snapped into action, building 500 wind farms per year, each with an average capacity of 50 MW, then onshore wind could generate 31.7% of the energy we need by the end of 2030.The issue of people not wanting to live near wind farms seems a thing of the past too, as our 2023 National Home Energy Survey strongly suggested. We found that one in two Brits would be happy to live next to an onshore wind farm, and only one in five answered with an outright ‘no'. Offshore windTime neededEnergy generatedNumber of sitesCost8 years520 TWh200£179 billionWhile the average onshore wind farm has a 50 MW capacity – enough to power 35,000 UK homes per year, on average – a typical offshore installation is much larger.The average offshore wind farm in Europe has a capacity of 788 MW – but technology is progressing quickly, so let’s be a bit more ambitious and say the average UK offshore wind farm built from here on will be 1,000 MW – enough to power 896,000 homes per year.Major offshore wind farms like the 1,400 MW Hornsea 2 – which became fully operational in 2022 – usually take around five years to go from the plans being submitted to being fully operational.But in September 2022, the UK government announced plans to slash the time it takes to get approval for an offshore wind farm from four years to one.With another year needed to actually build the farm, that means an overall production time of two years.If we could construct 1,000 MW farms, 50 at a time, then by 2030 we’d be able to generate 40% of the energy we need to power the UK.That’d mean overall, the UK would have an onshore and offshore wind capacity of 400,000 MW – which would be the biggest of any country if it existed now.In 2030 however, the world will have changed, and this figure will merely cast the UK as one of several wind power leaders.Many of the biggest nations have pledged to reach net zero, and wind is a vital part of achieving that goal for most of them.SolarTime neededEnergy generatedNumber of sitesCost6.9 years364 TWh3,458£647 billionThis is the most ambitious – and expensive – part of our plan.Expanding the UK’s solar power 30-fold would be extraordinary, but is completely necessary if we’re going to properly diversify our energy mix beyond wind.By expanding our storage capacity, we’ll be able to go green with confidence – but relying solely on wind is still a bad idea.It takes about a year to build a 120 MW solar panel site.If we constructed 500 sites per year, it’d take just 6.9 years until the UK was able to produce enough solar energy to meet 28% of this country’s demand.500 new solar farms per year is a steep task, but it’s completely possible.The UK has an enormous amount of space on which to install solar panels, and when it comes to installation companies, there are currently 643 solar panel installers certified by the Microgeneration Certification Scheme – with more to come.To carry out this plan while ensuring the solar industry can continue to meet consumer demand at the same time, the government must provide incentives and grants that allow more companies and individuals to engage with solar engineer training.HydroTime neededEnergy generatedNumber of sitesCost7.1 years2.8 TWh24,000£4.4 billionIt usually takes three years to build a 0.1 MW hydropower plant, which is far too long.Currently, 13.5 months of this process is down to bureaucracy. If the government acted decisively, it could cut this figure by six months, for an overall project time of 2 years and 4.5 months.The UK can expand its current hydropower capacity by 2,400 MW, according to the International Hydropower Association – so that’s what we’re going to do.We can further diversify our green energy mix, just by taking full advantage of our island status.If this plan was successful, hydropower would still only supply 0.22% of our energy – but every megawatt hour counts.Create the infrastructure to use green energyThe government’s next step would have to be organising a nationwide campaign to get households and businesses to install technology that can use all of this green energy.Without a gas grid, all buildings would have to be equipped to use electricity for heating.This would require generous grants and incentives on the one hand, and penalties on the other – plus an information drive to convince the public, and training programmes to ensure there were enough engineers.It’d be an incredible effort, requiring the installation of tens of millions of machines including heat pumps, electric boilers, infrared panels – with the added complication that many homes would have to be retrofitted.But David Toke, director of the 100% Renewable UK campaign, told us the process of creating a completely green energy mix started at home.When asked what the government should do to get us to 100% green energy, he said: “Make heat pumps, solar PV, and home batteries mandatory on new buildings.“That will get these green industries moving much more quickly and cost-effectively.”As well as gas, we’d also have to say goodbye to petrol.The government would have to offer grants for drivers and companies to buy electric vehicles, and invest more in the industry, to create enough charging stations and cars to meet demand.To ensure we can use all of this green energy, the government would also need to greatly expand the country’s storage capacity.The sun won’t always shine, the wind won’t always blow, and the waves won’t always produce the energy you might hope for – but with enough storage, this won’t matter. How much would it cost to go 100% green?Creating a completely green energy mix would cost the UK £1.23 trillion, according to our calculations.That’s roughly 4.4% of the total GDP (gross domestic product) we expect the UK to generate over the next eight years.That sounds like a lot of money – and it is – but at £154 billion per year, it’s the equivalent of giving the goal of reaching 100% green energy its own government department.And when you factor in the money we’ll lose by continuing to lean on unreliable fossil fuels, there’s no other option but to go all-in on renewables.With the climate in crisis and energy independence more important than ever, it’s crucial we take big swings – both to drive down our energy costs, and to fight climate change.The government must act now, with all the urgency and seriousness this situation deserves. Written by: Josh Jackman Lead Writer Josh has written about eco-friendly home improvements and climate change for the past four years. His work has been displayed on the front page of the Financial Times, he's been interviewed by BBC One's Rip-Off Britain, and he regularly features in The Telegraph and on BBC Radio.