September 21, 2016
A new dance for Gigha
Critics of renewable energy, particularly wind and solar, are always quick to point out that these are highly intermittent sources of energy. What are we supposed to do when the wind doesn’t blow and the sun doesn’t shine? And so the search has been on for a technical fix to the challenge of storing renewable energy. The community of Gigha were the original community energy trailblazers with their famous Dancing Ladies. Now they’re about to play another key role in Scotland’s journey towards a carbon-free future.
The island of Gigha is to play an important role in pioneering work to find a way to store power generated by wind turbines, which could revolutionise the global green energy industry.
The island is host to the first community-owned grid-connected wind farm in Scotland, the ‘Dancing Ladies’, which initially consisted of three turbines christened Faith, Hope and Charity. A fourth was added later, but its operation has had to be constrained.
The turbines are an important income stream for the Isle of Gigha Heritage Trust which led the headline community buyout of the island completed in 2002.
Now the turbines are to be connected to a “vanadium redox flow battery”, which is the size of a shipping container. It is a new piece of engineering which some hold could be a game-changer.
The likes of wind and solar power generators, have always had the problem of being intermittent energy sources. They often generate when the power is not needed on the grid, and have to be paid to shut down; or are inactive when the grid needs all the power it can get.
So the search has been on for a system which could store their power.
Energy can already be stored using technologies ranging from pumped hydro schemes to large-scale lithium-ion batteries.
But the UK government-funded trial on Gigha, will demonstrate that vanadium redox flow is now commercially viable, says Scott McGregor, chief executive of the device’s developer, the Jersey-registered ‘redT’ company.
He said “The technoloy has moved faster than anyone has expected and what you see today is a system that is a commodity product.”
The science is based on vanadium’s ability to hold different levels of electrical charge.
Hannah Smith, Policy Officer at industry body Scottish Renewables, said: ““Scotland’s islands have some of the most powerful renewable energy resources in Europe.
“What many of them lack is a strong connection to the national grid. Power produced there has to be consumed there as it simply has no route to a wider market.”
Energy storage technologies, such as batteries, presented an opportunity to use and export more of the green electricity generated, she said.
According to Community Energy Scotland: “This purpose designed and built battery could show the way for other rural comunities to harness the full potential of their renewable power.”