How a tiny west coast island led the way in renewable energy

“It was February 1st, 2008. We had this 3D map of Eigg with little lights around it and got the kids to switch it on.

“It had been a long haul, it was a really expensive project, we’d spent a long time making sure it was right.

“Just being able to do simple things, like get up at night and go for a pee without having to use a torch to see where you’re going, being able to buy a washing machine… it was life changing for people when it was switched on.”

The electric revolution of the late 19th century that had brought instant ‘flick of a switch’ power to homes across the land had taken its time reaching the small Hebridean island of Eigg.

Until February 2008, if islanders wanted to do anything that required power – whether popping on the toaster or watching television – they mostly had to a rely on dirty and expensive diesel generators.

A handful had installed micro hydro systems for some power, but it was far from enough to keep a typical home going.

This new scheme would electrify the whole island was a double first: continuous power was available for the first time to all residents and businesses, plus it was the first time renewable resources of wind, water and solar generated electricity had been integrated into a grid system designed to supply an isolated and scattered small community.

This was an entirely standalone electricity system; with no external input from a mainland utility, operated and maintained for the community by Eigg Electric Ltd, part of the Isle of Eigg Heritage Trust.

Even its repair and servicing would become the responsibility of a trained maintenance team of island residents.

“We didn’t have mains electricity, people had generators or micro hydro, and in general people didn’t have 24-hour power, just a generator on in the evening or not at all,” says Maggie, recalling the journey to the momentous switch on.

“On other places, like on Gigha which is closer to the mainland, the community had been able to put up turbines and export power to the grid which made money to put back into the community.

“But we weren’t able to do that.

“We’d built the pier centre with a shop and tearoom and put in a 6kw micro-hydro system to help run it.

“And we installed a micro-hydro system for a group of five houses. We thought we could do the same in small pockets all over Eigg but that wasn’t feasible.

“We started to look at full island systems, and that’s when it got real.”

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The idea on Eigg was to combine three technologies: a group of four small wind generators, a large 100kw hydro system aided by two smaller ones, and an array of ten solar electric panels sited at different locations around the island.

The total generating capacity of the whole system was approximately 184kW, controlled and distributed to all households and businesses via a high voltage 11km long grid.

Transformers converted the grid voltage to domestic voltage, and a bank of batteries capable of providing power to the whole island for up to 24hrs was designed to optimise energy usage.

As a backup, a pair of 70kW diesel generators stood in reserve, ready to be switched on automatically if the need arose.

A crucial component was that the project should have as little impact on the natural beauty of Eigg as possible: cable routes are buried, the only parts of the system visible above ground are the generators, the transformers and the building where the whole system is integrated and controlled.

None of this infrastructure came cheap: the islanders eventually secured finance from nine different sources for a project that topped £1.5m.

But that was a small price to pay for the vital spark that would bring electricity to this tiny kidney-shaped five miles by three patch of Scotland.

Maggie was the sole employee of the Isle of Eigg Heritage Trust at the time. Up to then, the island’s lack of electricity was perhaps its least curious feature.

The community had already seen off its previous owner Keith Schellenberg, who, after a decade of turbulence, sailed into the sunset with a crowd of cheering islanders waving him on his way.

“You never understood me, " he is said to have shouted as the boat carrying him away swung out to sea. "I always wanted to be one of you."

Then came a bidding war for the island, with Luciano Pavarotti among those keen to take over. He wanted to turn it into a centre for budding opera singers.

Instead, a global appeal for help landed £1.5 million from a mysterious and still anonymous female benefactor enabling islanders in partnership with the Scottish Wildlife Trust and Highland Council to purchase the island in 1997.

Against that background were resilient islanders who would have loved to have enjoyed the simplicity of switching on a kettle and running a freezer at the same time.

But even as February 2008 dawned, there were still concerns over how well it might work.

“We went with what the experts were telling us but didn’t really know how it would work until we switched it on, because the three technologies had never been combined to one system before,” adds Maggie.

“Then it’s one thing to get the system to work and another to maintain it. We were learning as we went.”

Solar panels turned out to be surprisingly effective during the long hours of daylight during May, June and July, helping to carry the island’s daytime use and charging the batteries for evening.

The three hydroelectric generators include the largest on the north side of the island behind Laig Bay, powered by water that travels half a mile and then down a 330ft drop, which generates up to 100kW, and the two smaller at up to 6kW each.

While the stiff wind sends the four wind turbines on a cliff below the 390m tip of An Sgùrr spinning, delivering up 24 kW of energy into the grid.

Usually, Eigg runs on 90-95% renewable energy. When the energy contained in the batteries slips below a certain level, the two 70kW backup generators kick in. At other times, excess power is targeted to community buildings such as the community hall, pier lobby and two churches.

The costs for householders, says Maggie, are comparable to mainland charges: around 27p per unit at the moment, which helps to cover the maintenance team who ensure the system ticks along nicely.

Crucial, however, is a self-imposed usage cap.

“We were not going to be able to supply enough power for everyone to have an unlimited supply,” says Maggie. “Rather than impose times per day for use, we decided on a 5kW cap - you can only use that much at any time.

“People were used to having to work around a limited power supply, they know you can’t put on a washing machine and a dryer and a kettle at the same time.

“Everyone has a monitor and, if they use too much power at once they knew it will trip their system. They’d need to have maintenance come out to fix it and that comes with a charge.

“We all have low energy lightbulbs, people tend to use laptops because they use less energy, televisions are low energy and big items like washing machines, tumble dryers and kettles are managed around all of that.

“When we have limited renewables, we ask people to keep energy use to a minimum, maybe avoid using the electric kettle, and people respond to that.”

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The renewables system can only do so much: most islanders have log burning stoves and kerosene boilers for heating.

The kerosene is a problem adds Maggie: “It has to be brought here, it’s messy.”

But the logs used for heat come from a well-tuned system, using wood from established local sources that is constantly replenished.

Rules introduced in April that new homes in Scotland should not use bioenergy sources such as wood and log burning stoves and instead use “climate-friendly” alternatives such as heat pumps or heat networks raises concerns on Eigg over how the current electric system might cope.

“We are working towards carbon net zero, and we’re hoping to increase our output with more wind turbines and bigger turbines,” adds Maggie.

“We’d hope to get to a point where we might be able to instal heat pumps for instance, but right now, we can’t offer that.

“Yet, if we want to build a new house, we have to put down a renewable source as a primary source of heating. We can’t just say we’ll put in a log burner.

“Banning wood stoves is not appropriate for rural areas like this. It’s stupid and it’s backwards.”

Powering Scotland’s islands

Scotland’s islanders have resilience built-in and have been at the forefront of developing innovative energy schemes.

On the small island of Iona, there are plans by Iona Renewables for a low-energy community-led landscape, including energy efficient buildings, renewable electricity and low carbon heat supply.

The vision involves decarbonising the island’s heat supply through a ground-source heat network that would extract energy from boreholes sunk almost 200m deep.

Hot water would then be pumped through pipes in what would be the first network of its kind in the UK and remove the need for the island to import its energy.

On Gigha, three 30-year-old wind turbines formed the first community-owned grid connected windfarm in Scotland when they were installed in 2004.

Dubbed ‘The Dancing Ladies’ they generate a combined 675kW of electricity – boosted in 2011 by a fourth, larger turbine.

Lack of infrastructure means the energy can’t be used locally and is instead sold to the National Grid. However, it returns a profit of around £150,000 a year to the island trust which goes to everything from new paths to electric bikes, wages for staff and housing.

With the turbines reaching the end of their lifespan, the Trust is considering two larger replacements capable of generating 850Kw of electricity each.

There’s also been talk of supplying electricity via a new cable from the windfarm straight to a halibut fish farm nearby, and whether oxygen waste from hydrogen produced by the turbines can be captured, bottled and sold to the farm, providing more income.

Meanwhile, the islands of Hoy, Islay, Great Cumbrae, Raasay, Barra and Yell have all been selected to be part of the Scottish government's Carbon Neutral Islands project.

The move is part of the Scottish government's 2045 net zero pledge and will see the islands share good practices and learnings.