The Big Six energy firms will face continued pressure from ministers to cut bills, with the Government warning that efforts to reduce costs for consumers are "not over yet".
Energy and Climate Change Secretary Amber Rudd said wholesale prices had remained low and she would continue to urge the industry to pass on savings in household bills.
Ms Rudd insisted she was "confident but not complacent" about efforts to keep the lights on but conceded that the new nuclear power station at Hinkley Point was not going to be generating electricity by the 2023 date originally set as a target.
At a Westminster lunch she told reporters that she was not going to ease up on the so-called Big Six energy firms - British Gas, SSE, E.ON, EDF, npower, and Scottish Power - after writing to them in June about their prices.
Ms Rudd said she would "like to see more progress" from the energy giants.
She said: "It's not over yet. I'm still pressing them. Wholesale prices have stayed low and I will continue to press them to cut those bills and keep them down and potentially, as British Gas has, to bring them down further."
Ms Rudd encouraged householders to switch suppliers to secure better deals for their electricity and gas.
"I will continue to press the energy companies and continue to talk to them about the impact of lower wholesale prices on the bill," she said. "On the average bill, it's about 46% of the cost - so there are some costs which aren't going down, which are actually going up, so we have to bear that in mind.
"But actually, if you shop around most bills are £100 less than they were this time last year."
Ms Rudd acknowledged delays in the process for building the UK's first new generation nuclear plant at Hinkley Point in Somerset, but said she expected an announcement on the project "very soon".
Reports have suggested an announcement on the deal between EDF and its Chinese partners could be made during Chinese president Xi Jinping's state visit next week.
Pressed on when the plant would be ready, Ms Rudd said: "EDF are going to be telling us when they expect it to start generating. It is a project which they are managing, although we are very supportive of it, so I don't have that date.
"It was going to be 2023, it may be slightly later than that."
Ms Rudd also said she was hopeful that shale gas extraction - by the controversial "fracking" process - would take place in the UK.
"I believe that we will see shale gas extraction in this country. We have put down additional instructions on the planning guidance in order to ensure that councils don't spend over a year - as they have in the past - thinking about this.
"I hope that if they stick to the timetable then we will be able to see the possibility of having shale extracted here."
The Cabinet minister, who insisted she had no plans to run for the leadership when David Cameron steps down, retained her marginal Hastings and Rye constituency in May.
She said the success was in part due to a new fast Hastings-London train she campaigned for, which has been nicknamed "the Arse" - the "Amber Rudd Seaside Express".