Martin Lewis issued a "monumental" warning to all energy customers ahead of the Ofgem price cap announcement this week.
The Money Saving Expert was asked about energy bills when he appeared on BBC's Sunday with Laura Kuenssberg yesterday.
Martin told Kuenssberg that although Ofgem's energy price cap for July is set to fall households won’t feel “any real benefit” from the drop.
He explained to the panel that the amount energy customers will pay from July is likely to drop between 15% to 20% - although this will not be confirmed until Ofgem's announcement on Thursday.
He said: "We're pretty sure it's in that ballpark. Then the next price cap is in October.
"The current prediction - and the further out you go it's more crystal ball gazing it is - is that it will drop a little bit more and then go up a little bit in January but still be in roughly the same amount it is now."
The Money Saving Expert website found noted that it "was an improvement" but "not the biggest improvement".
He also noted that all energy bill support, such as the £66/£67 discount, ended in April so everyone was already paying a lot more.
He added: "In practical terms, people aren't going to be feeling any real benefit, they're going to be paying the same that they were over winter and next winter is going to be the same as just gone - which is over double what we always thought."
Martin told the panel that there were "monumental questions" about consumer energy bills that were coming as there is currently no competition in the energy market.
He also said the people in charge had "clearly been asleep at the wheel for the last few years" and that things needed to change.
He added: "There's support for people on the lowest incomes, the important thing that will happen in July that we haven't seen since last October is that the energy price guarantee ends, which means the state subsidy of everyone's bills is ending.
"(It's) nine months earlier than it was predicted to, the expenditure on it is tens of billions of pounds less than than we thought.
"There is money to help those on middle and lower incomes and it's the people just above the threshold who don't get the cost of living help for whom £2,000 a year energy bills are unaffordable."
