Gas and electricity firm nPower announces an 10.4% average price rise for customers as of 1 December, adding £136 to annual household bills.
Around 3.1 million customers will be hit with the 10.4 per cent average bill increase, according to gas and electricity supplier nPower.
The price rise will mean an average dual fuel customer's annual bill rises by £136 a year, from £1,323 to £1,459.
Dual fuel is where your gas and electricity is supplied by the same firm.
Government blamed for energy price rises
Energy giant nPower blamed the rise on higher costs for fuel, delivering power to homes and meeting government schemes.
It insisted it makes a "fair return for delivering reliable energy to consumers".
But this offers cold comfort for customers who will see the increase take effect from 1 December as winter sets in.
The firm's price hike follows increases from two of the UK's other "big six" energy companies, SSE and British Gas.
British Gas & SSE also raise prices
British Gas dual fuel customers will see prices go up by 9.2 per cent on average from 23 November, raising typical annual bills from £1,321 to £1,444.
SSE, which also trades as Southern Electric, Swalec and Scottish Hydro, is increasing gas and electricity prices by an average of 8.2 per cent on 15 November, raising annual bills from £1,274 to £1,380.
Customer-owned energy firm Co-operative Energy also recently announced a price rise of 4.5 per cent.
It called on its larger rivals to put customers before profits, saying it was absorbing some of the increasing costs of buying wholesale energy.
Fears nuclear power could cause future price rises
And fears over much higher bill increases in future were heightened by the government announcement of a deal to build Britain's first nuclear power station for a generation.
French-owned energy firm EDF will build the £14 billion Hinkley Point C power station in Somerset, due to open in 2023.
This deal will see EDF paid £92.50 per megawatt hour for electricity produced at the plant - around double today's market rate.
The deal comes after lengthy wrangling over taxpayer subsidies.
Energy Secretary Ed Davey insisted the deal was a good one for consumers, who will save an average £77 on their annual bills by 2030 thanks to the new nuclear programme.
But consumer body Which? called for a clause which would see consumers receive a refund if it turns out the government has overpaid on the deal for the plant.
Richard Lloyd, executive director of Which?, said: "Rising energy bills are one of the top concerns for cash-strapped consumers.
"So everyone will want to be assured that the price the government has agreed for new nuclear power is fair."
Price rise 'unsurprising'
Commenting on nPower's price rise announcement, Kate Rose, head of gas and electricity at Confused.com said it was "unsurprising".
"Today's announcement from npower is unsurprising following the recent price rises announced by SSE and British Gas.
"However, with an average dual fuel increase of 10.4 per cent, this is the biggest price hike we have seen so far.
"It is not what consumers want to hear as the winter weather leads us all to turn on the heating.
"As more suppliers look set to announce price rises in the coming weeks, we urge consumers to act quickly to protect themselves from increasing bills."
Fixed deals could help cut bills
Rose says opting for a fixed gas and electricity tariff could help cut bills.
Gas and electricity tariffs are either variable - where prices change in line with the cost of energy - or fixed - where prices are guaranteed for a set period of time.
"There are a variety of competitive fixed deals in the market.
"However, with the increasing possibility that these tariffs could be withdrawn as further hikes are announced, it really is vital that consumers act now to save themselves money.
"Comparison sites such as Confused.com are free to use and display all available tariffs, making it quick and easy to switch to a new tariff or supplier."
See our gas and electricity best buy table for the latest fixed and variable deals.
How to search for the best gas & electricity deal
- You'll be asked to enter your postcode and details of your current gas and electricity supplier, including the name of your tariff. You should be able to find the name of your tariff on a bill but if not give your current supplier a call and ask. There are hundreds to tariffs on the market so it pays to enter the correct tariff so you get the most accurate price comparison.
- You'll be asked to enter your annual spend on your bill, or your annual usage. For the most accurate price comparison, enter your usage. You can find this out by calling your current supplier and asking for your usage for the past 12 months, in kilowatt hours (kWh).
- If you don't know your usage - if you've moved into a new property for example, you'll be asked if you're a low, medium or high energy user. Find out what category you fall into.
- The search results will show you the cheapest deals for dual fuel (gas and electricity from the same supplier), as well as the cheapest deals for gas and electricity separately. It's worth checking out the cost of separate deals as while duel fuel is often cheaper, this is not always the case.
- You're also able to enter how you'd like to pay your bill. It is almost always cheaper to pay by direct debit. Energy firms claim this is because the payment is cheaper to process but the fact is that if you pay by direct debit then your payment is guaranteed, unlike paying on receipt of bill. So suppliers are happy to offer discounts for customers who pay by direct debit.
Find out the top 10 energy myths and arm yourself with the facts before making the switch to a new gas or electricity supplier. Read what happens after you've committed to a new energy supplier. Here we've put together the answers to your most frequently answered energy questions. Or if your puzzled by your bill read our simple guide to understanding your bill.
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