The UK's first island grid system is up and running at the Centre for Alternative Technology (CAT) in Wales.
It will allow the Centre to use the power it generates itself instead of relying on national grid supplies and help them reduce their carbon footprint.
Centralised electricity systems like the national grid waste around 65 per cent of energy through heat loss in power stations and transmission lines before reaching our homes.
Previously, any power generated by the Centre's wind turbines or solar panels was exported to the national grid. Now the power will be used around the Centre, with only the excess exported to the national grid.
'Even if you've got a wind turbine on the roof, if the grid goes down you're in the dark like everyone else,' said Alex Randall from CAT.
'We can be on or off grid whenever we like now. At quiet times, our island grid sends any excess to the national grid and at peak times it imports any extra required,' said Randall.
Centre for Alternative Technology (CAT)