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Last year, Swansea University's Specific innovation centre unveiled the UK's first energy-positive classroom.
Now plans have been approved which will see the same approach adopted in 16 new homes to be built by social housing group Pobl, in Neath Port Talbot.
The report was carried out by an independent energy consultant.
The concept uses a combination of solar cells, battery storage and a revolutionary steel frame which draws solar-heated air through tiny perforations for heating and warm water.
Andris Bankovskis, a member of government body, the Panel of Technical Experts on Electricity Market Reform, based his report on the Neath plans.
But he scaled them up to reflect the potential savings if the technology and approach was applied to a million homes.
He concluded the average saving on energy bills could be at least £600 per household, not including any additional benefits from solar feed-in tariffs.
In addition to consumer benefits, Mr Bankovskis suggested a host of environmental benefits.
These include a decrease in carbon dioxide emissions of nearly 80 million tonnes over 40 years and a reduction of 3,000 Megawatts in peak generating capacity - equivalent to the output of a very large power station.
He said: "The combination of photovoltaic cells and battery storage means that the homes could harvest energy from sunlight, and hold it until it is needed at times of peak demand.
"It also means that provided we can make smart networks a reality, we can better control our energy and share it more easily around a locality, reducing stress on the grid.
"The potential savings amount to over £11bn over 40 years, and that's before you factor in the opportunities for investment and job creation."
Set for completion in 2019, the Neath homes - being built on behalf of Neath Port Talbot council - will be fitted with a steel roof, on to which the photovoltaic cells are integrated, allowing them to operate in areas with lower levels of sunlight.
Electricity will be stored in batteries until needed, and shared within the community.
There will also be the opportunity to charge electric vehicles using the excess energy.
Water heating will come from a solar heat collector on south facing walls, as the homes will use no gas.
In time, it is hoped this system could operate over an entire year; allowing heat to be captured in summer and stored for use during the winter.
Kevin Bygate, chief executive at Specific, said: "Individually, all these technologies exist commercially, what's new is the way we've been able to bring them together in a form which is easy and cost-effective, through integration, allowing roll-out on a large scale.
"We're focusing on new-builds at the moment, where there is significant opportunity to help those in fuel poverty, but there's no reason why they couldn't be retro-fitted to existing homes."
He added: "Buildings count for around half of all energy usage, so adopting this system can have a massive effect on consumption for a comparatively low cost."
If the Neath project is successful, there is the opportunity to roll out the system to a further 1,200 homes, as part of the £1.3bn Swansea Bay City Deal.
President Barack Obama has arrived in Cuba for a historic visit to the island and talks with its communist leader.
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