There’s a long series of unfunny jokes about solar power and Ireland – the whole comparison of buying solar panels in Ireland being like the proverbial chocolate teapot. As a former resident of Galway, I can confirm that, yes, it does indeed rain a lot in this country, but to assume that makes solar panels unworkable here is to massively misunderstand how solar panels work.
In fact, according to Bord Gáis Energy’s recent solar survey, modern solar panels work all year round, and Ireland is already seeing record levels of solar power on the grid. Last month, solar energy generated more than 6.5 per cent of Ireland’s electricity, with 173,163 megawatt-hours produced, more than double the amount this time last year.
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That’s a lot of power, and it means that the amount of solar energy generated in just one month in Ireland could be used to charge up 2,886,050 electric cars, assuming they each took 60kW of that energy. For anyone asking, “but how are we going to charge all these electric cars?”, well, there’s your answer.
Okay, that’s the macro-level stuff. What can solar power do directly for you and your EV? Well, we asked the experts at Bord Gáis Energy exactly how much money you could potentially save if you could charge your EV from sunlight.
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Assuming that an average EV has a battery capacity of somewhere between 65kW and 75kW, how many panels would you actually need, for a start? According to Bord Gáis Energy, it depends on the property – factors like roof orientation, shading and weather conditions all make a difference. As a guide, SEAI notes that a well-located 3kW system – around 20-metres square of panels – typically generates about 2,600kW per year, which is over 40 per cent of the average annual electricity demand of an Irish home. That level of generation could equate to dozens of full EV charges, but of course, in reality, much of it will also be used to run the home’s day-to-day appliances.
Generally speaking, people won’t be charging their electric car much during the day. That’s when it’s in use, and most people are already cottoning on to the idea of charging at night, when electricity is at its cheapest, but – kind of obviously – that won’t work for solar panels, so is the best thing to do to get a storage battery, which soaks up the solar sunlight during the day, and then releases it back to the car at night (and which also acts as a handy buffer between you and any powercuts)?
Actually, says Bord Gáis, the best thing to do is to turn the question around the other way, and think of your EV as the storage battery (which it is, sort of, it just has wheels and seats too).
While a home battery can store solar power for later use, the most effective way to charge an EV is to use a cheap night-rate electricity supply tariff, such as Bord Gáis’ EV Urban plan. This offers a special overnight charging rate of 7.45c per kWh between 2am and 5am, so you can schedule their charging at the lowest cost. Most households will use their solar to offset daytime electricity use in the home, while relying on this kind of cheap EV tariff for their car, so you’re in a sense paying to charge the car, but getting the rest of your energy for (almost) free.
Of course, that doesn’t answer the standard criticism of those not paying attention – that it’s too wet and cloudy over our little island for solar energy to be much good to us. Can we finally dispel that myth? Bord Gáis says we can, noting that one of the biggest myths is that solar only works in hot sunshine.
In reality, panels generate electricity from light, not heat – so they don’t need hot weather, just bright conditions. They will still produce power on cloudy or rainy days, though output is reduced. Ireland’s mild climate and extended daylight hours in summer make it a good environment for solar, and over the course of the year, the claim is that panels can still reduce household bills by 50–70 per cent.
Okay, but solar panels don’t grow on trees, and they cost money to install, so how long are you going to have to wait around to get your money back? Apparently, the straightforward answer is five years – a typical installation costs €8,000 –€10,000 before grants, and there’s an SEAI grant of up to €1,800 with many suppliers, including Bord Gáis, offering zero per cent finance too.
Once installed, systems usually pay for themselves in about five years, with panels lasting 25–30 years – leaving two decades or more of low-cost, clean energy and the potential to earn by exporting surplus back to the grid at 18c per kWh that you generate over and above your energy needs. That can, potentially, add up to a tidy sum each year, maybe as much as €500, which would more than cover your EV charging cost.
We recently ran the numbers on the cost of charging an average-sized family EV, using an MG 4 hatchback as the sample car. The costs work out like this: Assuming you’re on Bord Gáis’ 7c per kWh night rate between 2am and 5am, and the rest of the charge at the standard night time rate of 22c per kWh each full charge of the MG’s 64kW battery will cost you €10.65, giving you an official range of up to 450km, but more like 400km in real-world conditions on average.
To cover the average Irish annual mileage of 14,000km, that means you’ll need 32 full charges, which equates to a cost of around €320 for your EV charging. Make the most of that solar potential, and that essentially means free charging, plus a bit left over (leaving aside paying for the solar installation, of course).
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Valerie Hand, retrofit manager of Bord Gáis Energy, said: “The gap in knowledge of the benefits of solar is considerable. Many don’t realise that it works brilliantly in Irish weather – and that their roof could not only be saving them money but also earning them money. We want to help people on their Net Zero journey and believe that solar power will play an integral role in achieving a greener, fairer future while supporting the government’s Climate Action Plan targets.”
