The CEO of Octopus Energy has warned the worst of price rises "have not yet passed on to customers" as the company slashes bills by up to half for lucky customers in three areas.
In an email to energy users, Greg Jackson said global gas prices are around eight times higher due to Vladimir Putin's invasion of Ukraine.
He claimed that as the energy price cap is based on wholesale costs, the worst of these hikes "have not yet passed on" to Brits.
His comments come as the energy firm announces plans to give customers cheaper energy bills if they are fortunate enough to live in three areas that are supplied with renewable wind power.
The founder wrote: "Make no mistake, this is a fossil fuel crisis. As a direct result of Putin's invasion of Ukraine, global gas prices are astronomical - currently around eight times higher than usual.
"And because of the way the UK's energy system works, the price of electricity (even renewable electricity) is largely set by the price of gas.
"This needs to change - a review is underway, but it won't change things quickly enough to address the crisis."
He added: "Gas prices have been like this for almost a year now, but as the energy price cap is based on wholesale costs, the worst of these rises have not yet passed on to customers."
An extract of the letter was shared by a customer to Twitter, where Mr Jackson reiterated his claim that energy price rises are down to Putin's actions.
He tweeted yesterday: "Today's cost crisis is driven by the weaponisation of gas prices by Putin, and our over-reliance on global fossil fuels.
"Short-term, we need help for households, to bring bills down and cut inflation. And in parallel we need electrification & market reform for permanent solutions."
Octopus, which has a "Fan Club" that gives cheaper electricity if you live near wind turbines, has expanded a scheme that allows households to get up to £350 off their annual bills.
The energy tariff is already available in two locations, but now Octopus has launched its third local tariff in Halifax in Yorkshire.
When the wind blows, the unique tariff can provide customers in the HX2 postcode area of Halifax with a discount of up to 50% off the unit rate, which the company estimates can save households around £350 on their annual bill.
The other areas providing customers with cheaper electricity are in Market Weighton in East Yorkshire, and Caerphilly in South Wales.
First launched in 2021, customers in these areas get 100% renewable electricity whenever their local turbines - which can power 800 homes - are spinning.
Now, up to 10,000 people have asked Octopus Energy to install a local turbine near their homes so they can have access to cheaper electricity.
Zoisa North-Bond, chief executive of Octopus Energy Generation, said: “We’ve been blown away by the volume of requests and positive sentiment towards our Fan Club, which offers people 100% local green energy at discounted rates.
“Welcoming customers onto our Number 3 Fan in Halifax means more people can benefit from cheap, green energy when it’s abundant locally. This is especially important as people are facing much higher energy bills this winter.
“But we are not going to stop here – we are working round the clock to add many more wind turbines to our Fan Club model, putting money back into people’s pockets whilst driving renewables at scale.”
Energy bills could rise even higher than previously feared, reaching nearly £5,500 a year from the spring, experts have warned.
Forecasters said that if gas prices don't drop in the next few months, the energy price cap could hit £4,650 in January and £5,456 by April - a mammoth £104 a week.
