To Stop Wasting Extra Wind Energy, There’s a Plan to Send It to the Country’s Coldest Homes

It’s not uncommon for Eirgrid, the overseers of the country’s electricity wires, cables and substations, to tell wind farms that they have to switch off, a notice known as “dispatch down”.

In 2021, around 750Gwh of potential renewable wind energy was lost when turbines were told to shut down because the grid couldn’t handle it at that moment.

That’s roughly equal to what 178,000 households in Ireland use in electricity each year.

Wasting clean energy during a climate crisis and amid rising energy poverty bothers Derek Roddy, one of the founders of the social enterprise and non-profit EnergyCloud.

“It’s like a hidden leak in the bucket that no one mentions,” he said.

Much of the government’s focus has understandably been on readying the grid for the future expansion of wind energy generation, says Roddy.

But, he and his partners at EnergyCloud have also been busy with a new way to use the wind power that is already right there but lost, the volume of which is likely to rise as wind farms multiply.

The idea is that Eirgrid would no longer tell wind farmers to turn off when the grid struggles to cope with bursts of wind energy.

It would instead tell EnergyCloud to turn on a switch on hot water tanks in households living in energy poverty, so that they find hot water ready for them in the morning, and heated not by dirty fossil fuels but by clean wind.

A current pilot of 50 social homes is just the start, says Roddy. While there are technical issues to iron out, it has the potential to be rolled out to thousands or even hundreds of thousands more.

Pressing Pause

Wind farmers are told to power down, or “dispatch down”, for two reasons.

If there is too much wind energy zipping through the grid in parts of the country and it can’t handle it, which is known as “constraint”.

Or when the need for steady frequency levels on the overall grid means it can’t take any more wind, which is known as “curtailment”.

EnergyCloud is looking at wind energy lost from curtailment at the moment, says Roddy. Constraint will hopefully come later, he says.

For households, the tech is simple.

Most hot water tanks have an electrical switch to turn on the element to heat up the water, says Roddy, but it’s rarely used. Generally, heating water with electricity rather than fossil fuels is way more costly.

EnergyCloud puts in a remote switch to flick the electricity on at times where storms and strong winds mean there is too much wind energy for the electricity grid to handle. They also stick a sensor on the tank so people can see how much hot water they have.

When the gas boiler might usually turn on to heat it up in the morning, it wouldn’t have to, says Roddy. The water would already be hot.

If EnergyCloud were to switch on 1 million hot water tanks this second, he says, it would take about 3Gwh of electricity.

Electrical demand in Ireland usually ticks along around 2.5 to 3 Gwh, he says. “We would be doubling the demand for energy.”

“You’ll basically have created the biggest battery in Europe, probably one of the biggest batteries in the world,” he says, “by just joining up people’s hot water tanks in people’s homes.”

EnergyCloud wants to be careful about what it is promising, he says. “What we’re talking about doing was a bath night a week, just as a starting point.”

It isn’t really about the tech, says Roddy, who also runs a company called Climote, which makes energy-saving devices.

It is as much about getting the right people together through a not-for-profit – partners include Climote, Wind Energy Ireland, Eirgrid and Clúid Housing – and working out how to do this, he says.

Who Should Get It?

Fifty of Clúid Housing’s social homes are being rigged with switches and sensors at the moment for the pilot, says Jo Whittall, director of property at the approved housing body.

The homes are all over Ireland, with a third in the greater Dublin area, he says.

Some Clúid Housing tenants can afford just €20 a week for heating, he says. “That’s what they spend and they are cold and uncomfortable for the rest of it.”

They turn to public libraries to keep warm during the day, he says. “We know that they wrap themselves in blankets and duvets and go to bed early in the winter.”

At the moment, Sharon Reville, a Clúid Housing tenant in Clondalkin, can afford to keep comfortable, she says.

But she is increasingly cautious about energy use, she says, careful not to leave appliances on standby, lights on in an empty room, or to make a song and dance about showers.

“What I would probably do a bit more is, if it is a bit chilly, be putting on more layers rather than turning up the thermostat,” she says.

Signing up for the pilot was a no-brainer, says Reville, who recently got the EnergyCloud switch in her home. “If you’re going to get something for free.”

Also, the new sensor on the hot water tank showing how much hot water it has ready is a massive help, she says.

Roddy, of EnergyCloud, has tried not to get tangled early on in working out what would be the fairest way to choose households to benefit. That might have stalled the project, he says.

Definitions of energy poverty can vary. A 2015 government analysis said that 28 percent of households in Ireland, meaning 460,000, were spending more than 10 percent of their income on energy needs, and so in fuel poverty.

The Economic and Social Research Institute (ESRI) said that 17.5 percent of households were in fuel poverty in 2020, using the same threshold.

Meanwhile, in 2020, 3.4 percent of those who responded to the Central Statistics Office’s annual survey on income and living conditions said they were unable to afford to keep their homes adequately warm.

A spokesperson for the Sustainable Energy Authority of Ireland said that it is part of a network alongside ESRI and government departments, to work out what data is needed to better measure fuel poverty.

The EnergyCloud pilot has started with social homes. But rolling it out to those who qualify for the fuel allowance would maybe be logical in future, says Roddy.

EnergyCloud’s modelling suggests that, if it had access to the hot water tanks of 460,000 households in energy poverty, they could use up to 89 percent of all wind energy currently curtailed at night. “It’s staggering,” he says.

Can It Last?

“The idea of just going out and doing something, and then it works for 12 months, is not really clever,” says Roddy.

Making sure EnergyCloud has a sustainable model has been top of his mind and colleagues’ minds, he says.

Roddy says energy providers have been positive so far about the scheme. SSE Airtricity is giving free energy for the pilot, he says.

Noel Cunniffe, the CEO of Wind Energy Ireland, the representative body of the wind energy industry, said the first attraction for wind energy providers is that it is the right thing to do. “It’s genuinely as simple as that.”

Especially, given the context of rising energy costs driven by escalating fossil fuel prices, says Cunniffe, who is also on the board of EnergyCloud.

“It just makes so much sense to try and use that energy that’s available and that’s there and it’s just not being used right now to use that to power the homes of families and people that are living in fuel poverty,” he said.

Roddy says that wind farmers also have conditions in licences and regulation agreements that they have to give something back to communities where they build wind farms.

“It’s not unsubstantial,” he says. “By 2025 to 2030, that could represent about €30 [million] to €40 million a year.”

A wind generator could meet that by sponsoring a GAA club, but that’s not linked to why they are there, he says.

But energy is, says Roddy, making the idea that there is surplus energy and it’s not being given to the community as gain seem mad.

Details around who would pay what long-term, whether the electricity would be free or heavily discounted, say, are still to be worked out.

“There’s a long way to go,” says Cunniffe, of Wind Energy Ireland.

There are still technical considerations to rolling it out at scale, he says, like how close homes are to wind farms are, or how close homes are to each other and how switching on loads of immersions all at once would affect demand on the grid.

Roddy says that even with Eirgrid working to modernise the grid so there is less down-time for renewables, the overall amount of surplus wind energy is expected to grow as wind farms do.

That’s “the really exciting piece on this”, he says.