Excess solar energy; sell back to the grid or energy storage solutions?

The roofing and solar experts at Marley, are pre-empting a significant rise in homeowners, developers and commercial property owners seeking energy storage solutions in 2023 to capitalise on excess energy generated from solar tiles.

From Marley’s latest study of Google search data [1], it found a 47% increase in searches for “energy storage” in the last 12 months alone, showing a much greater demand than this time last year, and already amassing over 34k searches in the UK in this time period[2].

Solar tile demand as electricity prices rocket

Sam Tebbs, Marley’s Special Project Manager for Solar systems and Training is attributing this energy storage trend to the current energy crisis and wider consumer and industry shift to solar solutions: “The dubbed ‘energy crisis’ - which has been at the forefront of social and political conversations since last August - has naturally driven more domestic customers, architects, developers, and commercial property owners to seek alternative energy solutions. Solar energy has become increasingly attractive as electricity providers hike prices because it instead offers customers cost stability, a climate-friendly alternative, and guaranteed supply, especially with the uncertainty surrounding energy prices in April 2023 following the government’s Autumn Statement.

“As this demand increases, properties generating solar power often produce energy that is not required by the homeowner at that point in the day. While they can sell this back to grid via the SEG scheme, extremely high energy costs from suppliers and winter blackout rumours are instead driving customers to seek storage solutions to achieve self-sufficiency and protect their supply,” adds Tebbs.

According to the latest data [3] from industry association Solar Energy UK, the rooftop solar demand has significantly increased this year. It found that the deployment of new capacity is taking place at a record pace, as 95 megawatts was fitted to residential rooftops in the second quarter of 2022; almost triple the same period last year.

Storing energy vs selling back to the grid

As solar tiles enable properties to generate their own electricity rather than relying on the main grid for power, quantities generated depend on a variety of factors such as weather, time of year, and ultimately user habits and as such can mean there is excess energy produced at certain points in the day.

Historically, this energy would be sold back to the national grid as part of the SEG scheme (Smart Export Guarantee); the government backed initiative that was introduced back in January 2020.

Based on the energy price guarantee [4] which came into effect on 1st October, the current electricity charge per unit is £0.34 per/kWh for users of the national supply. For those with solar panels on a variable SEG tariff, you will be at a loss by the smart export costs to later re-buy.

Marley has crunched the current figures by suppliers on variable rates [5] to calculate how much you could make or lose by selling back to the grid. At best, Octopus is currently selling 34p per/kWh, but on average, the rate across the variable tariffs is 0.078, or 7.8p per kWh to export back to the grid. This is in effect a loss of 26.2p per/kWh, as customers will only be paid 7.8p, and if they later needed electricity from a supplier, they would be buying back at the current unit price of 34p.

Tebbs indicates that these latest figures show that this is not always the best choice: “It is simply no longer as financially viable for solar panel owners to benefit from SEG, compared to the original feeding tariff. As there is such a disparity from selling and purchasing costs. This is what, in part, will be driving the demand for energy storage solutions which can be more cost effective in some cases especially when the occupant is not at the property during the day. Storing excess energy from solar panels is often the best way to save money and operate your energy efficiently. But with a 47% increase in ‘energy storage’ searches in the past 12 months, I think the rumoured cap increase and adoption of solar panels will fuel this further, and we could see a significant growth by the second quarter of next year.”

Energy storage - the 2023 solar trend

Samuel Tebbs from Marley summarises: “Our solar roof tile orders increased significantly in 2022 compared to the previous year’s sales, and we have trained hundreds of installers to help future proof their business and to meet buyer demand. We can confidently predict even bigger solar growth in 2023 as energy storage solutions enter the market to meet demand.”

To learn more about renewable energy solutions, we have courses for Part L’s conservation of fuel and power here.

^References:

^{[1] - Google Search Data - October 2021 search volume was 49, compared to October 2022’s search volume of 72.
[2] - SEMrush keyword overview records 2.9k direct term searches per month for “energy storage”.
[3] - Solar Energy UK press release - https://solarenergyuk.org/news/energy-price-crisis-drives-massive-growth-in-uk-solar-power/
[4] - Energy Price Guarantee, 01 October 2022 - https://www.ofgem.gov.uk/information-consumers/energy-advice-households/check-if-energy-price-cap-affects-you
[5] - Current smart export guarantee rates as of 01 October 2022 - https://www.moneysavingexpert.com/utilities/free-solar-panels/}