Australian households are expected to save an average of $97 on their power bills over the next three years.
But critics argue the potential relief represents a small fraction of recent price hikes, while households in Western Australian will not reap the benefits.
The rule maker for Australian electricity and gas markets expects household power prices to fall by about $32 a year by 2022.
The Australian Energy Market Commission puts the 7.1 per cent drop down to a rapid influx of renewable energy, falling network costs and the scheduled abolition of the Renewable Energy Target.
The biggest savings will be in Queensland, followed by NSW and Victoria.
AEMC chairman John Pierce expects reductions across all states in the national electricity market.
Western Australia, which is not part of the national grid, is expected to buck the downward trend, with annual bills tipped to rise by $100.
"While the overall national trend is down all across the supply chain there are regional differences across states and territories that will affect price outcomes," Mr Pierce said on Monday.
"Overall, a representative consumer will pay around $97 less than today by June 2022."
Federal Energy Minister Angus Taylor welcomed the AEMC predictions but said there was more to be done.
"Prices have started to turn the corner," Mr Taylor said.
"The government has carefully built a range of levers and tools to lower energy prices and increase reliability in a rapidly changing (national energy market) to ensure the lights stay on."
However, his political opponents dismissed the price predictions as "a triumph of hope over experience".
Labor's energy spokesman Mark Butler said wholesale power prices had soared by more than 20 per cent over the past 15 months.
Mr Butler said a 7.1 per cent saving over the next three years would only recover one-third of the increases seen under Angus Taylor's time as energy minister.
"In any event, the only reason for any modest price relief is the investment boom of renewable energy that occurred under Labor's renewable energy target - a policy Angus Taylor has consistently opposed," he said.
Average household power bills reached $1370 during the 2018/19 financial year and have been calculated to fall to $1273 by June 2022.
This general decrease will only happen after the current financial year, which will see peak prices in all states except Queensland.
The drop in prices will be seen more clearly in the sunshine state, where annual residential bills are expected to be $278 less in 2022 than they were in July 2019.
The Northern Territory was not included in the report, as it only recent opened to independent generators and the value of contracts with retailers was kept secret.
Australian Associated Press