Householders have been warned to prepare for higher prices of electricity, gas and home-heating oil this winter.
A move to hike prices will reverse almost two years of energy cost reductions.
The return to price increases has prompted warnings to householders to lock into discount deals now, and those who use home heating oil are advised to get their tanks filled before prices start to surge.
It comes after the wholesale price of gas, a key component in the production of electricity and used for domestic gas supply, rose by 30pc in the year.
Wholesale gas prices are now back at levels not seen since last February, according to the Vayu energy report.
Oil production and refining facilities in the Gulf Coast region of the US have been shut down due to Hurricane Harvey, equating to almost 15pc of the US refining capacity.
"Oil markets are expected to keep the bullish tone as long as refining capacity remains impacted as a result of the hurricane," Vayu said.
Petrol and diesel retailers have already warned that they are putting up prices at the pumps this week, in a move that will cost drivers up to an extra €2 to fill up.
Experts also pointed out that although energy prices have been falling overall for two years, many suppliers have only cut them marginally.
Eoin Clarke of energy price comparison site Switcher.ie said that prices for consumers were now likely to rise.
"For anyone who heats their home using heating oil, if you can afford it, now could be a good time to fill the tank.
Market
"This means that, if prices do go up, you'll have a full tank to work through before you have to buy at the higher price. And if prices don't go up, you'll have one of those winter bills out of the way early."
He said there have been rises in the UK market, with the most recent one a rise of 12.5pc in electricity prices from British Gas. Energy providers here tend to follow what happens in the UK.
Mr Clarke added: "The increase in wholesale prices could signal that residential price rises are on the way for consumers."
Dermott Jewell of the Consumers' Association said commodity traders have been inching up their prices for wholesale oil and gas in the last few months. He warned that events like Hurricane Harvey may be used by suppliers to hike prices for consumers.
"This news could still be 'represented' by suppliers as the occasion to increase prices by a mile," Mr Jewell said.
He called for transparency in all energy pricing.
Mark Whelan of price comparison site Bonkers.ie said: "Consumers who use home heating oil, such as kerosene or gas oil, should also brace themselves for an uncertain winter."
Energy experts said most providers offer discounts for paying by direct debit and receiving bills online, and many offer retention deals to long-term customers.
The average dual-fuel customer can save up to €318 per year by switching from standard tariffs to the cheapest electricity and gas deals.
Anyone eligible for the State-paid fuel allowance was advised to check if they are entitled to receive it. For the first time this year, those getting the €585 allowance can opt to have it paid in two lump sums, instead of weekly.