Net-billing and rampant PV curtailments should make individual battery storage a shoo-in, so what’s going wrong?

When it comes to solar power, the ultimate dream is self-sufficiency – both on the macro level, as an island (since we have so much sunshine), and on the micro, household level.

Unfortunately, the current situation is a long way from that – largely because the power grid isn’t up to scratch, curtailing (i.e. cutting off) photovoltaic systems when they produce more than it can handle.

“Instead of storing [energy] for later use, they simply shut it off. No warning, no compensation. Just wasted sunshine,” wrote Orestis Georgiou, an R&D expert who also blogs, in a post titled ‘Why Cyprus is Throwing Away Solar Energy, and How We Can Fix It’ that was written a year ago but remains relevant.

“Even though my solar panels could be producing more energy, feeding it into the grid, and offsetting my monthly electricity costs, the grid operator is forcing them to shut down,” he goes on.

“So, instead of banking those extra kilowatt-hours for later use, I end up buying more electricity from the EAC – which, of course, still relies heavily on fossil fuels.

“It’s a double hit: I lose the free energy my system could generate, and I have to pay for dirtier, more expensive power instead.”

According to data by CyprusGrid, 162 gigawatt-hours (GWh) have been curtailed in the first five months of 2026 – an incredible 65 per cent of the total power we could have generated during that period. Surely, this can’t go on. 

Georgiou’s suggested solution is household battery storage, allowing every PV system to store its own excess energy. People could thus “charge their batteries when the sun is shining and use that energy at night, reducing demand on the grid and eliminating curtailment altogether”.

His idea is even more relevant now – because a year ago we still had a net metering system, which (though still subject to curtailment) allowed ‘prosumers’ to be credited for excess energy and offset it for a later time, so they could produce in spring, for instance, and use it in summer, when demand is higher.

That made batteries – which usually store for same-day (actually same-night) use – less attractive. Since the beginning of this year, however, net metering has been replaced by net billing which merely credits a prosumer for exported excess energy on their current bill (and at a lower, wholesale rate, so they still pay the difference), without allowing any offset.  

Indeed, the case for using batteries has become so strong that PV systems will apparently have to include a storage system to qualify for state subsidies – though no subsidy schemes have been announced yet.

Despite all this, it doesn’t look like the idea of individual battery storage is catching on.

Data supplied by the EAC paints a sobering picture. Applications for PV systems have plummeted, reflecting the end of net metering and the old ‘Photovoltaics for All’ subsidy scheme – from 38,856 in 2025 to 1,835 so far in 2026.

Applications for systems that include battery storage have climbed, but just barely, from 89 (0.2 per cent) last year to 137 so far this year, 7.4 per cent of the much smaller total.

“When it comes to grid-connected systems… I haven’t heard of anyone installing batteries so far,” Nicholas Christofides, an associate professor at Frederick University who’s been involved with PV systems (mainly on the design side) since 2005, told the Cyprus Mail. “Off-grid, that’s another story.”

The reason, he says, is simple. Each case is different, for sure – but in most cases, when consumers do a basic benefit/cost analysis, the numbers just don’t add up.

Battery lifetime is one issue. Fanos Karantonis, president of the Cyprus Association of Renewable Energy Enterprises (Seapek), cites a figure of eight to 10 years – but it depends on the type, and ‘design lifetime’ may be different from actual lifetime. “It’s a bit of a lottery,” opines Christofides.

And then there’s the cost. As a ballpark figure, Karantonis mentions €300-400 per kilowatt-hour (kWh) of daily storage – which actually seems a bit low. Other sources, like Smart Solar Cyprus, cite €8,000-10,000 for a 10 kWh home system.

How many kWh does a storage system need? Cyprus’ electricity consumption is approximately 4,000 kWh per person annually, meaning around 11 kWh a day (and night) for a one-person household.

That said, there’s a twist in that batteries can’t be overused. Isaias Kammitsis, who has an off-grid PV/battery system in the Troodos mountains (not by choice; the house is too remote to be part of the grid), cautions that battery life is degraded if you regularly go below 50 per cent. So a household really needs a battery capable of storing about twice its needs.

And of course there’s another twist, in that 11 kWh is an average – and consumption fluctuates wildly over the course of a year, low in spring and autumn, high in winter and especially summer, when it could easily be double that.

The numbers will vary, of course. But it’s clear that, if the idea is to avoid curtailment by essentially becoming your own mini-grid – and using batteries to run a family home throughout the year, with heating and air-conditioning – the set-up cost is likely to be prohibitive. 

Is that the end of the story? Actually, no. The benefit/cost calculation may not work out for individual households – but it could still make sense on a national level.

In his blog post, Georgiou does some calculations and concludes that we (meaning Cyprus) could save money by investing in PV systems with battery storage – even increasing the proportion to 50 per cent of all households, instead of the current 10 per cent – given the savings in EAC emission fines, and the potential for using energy that’s now being curtailed.

That’s just one blogger’s view, of course. But it seems like it could be useful for the state to study the pros and cons of household battery storage.

Alas, the state is going in a different direction.

There’s a hitherto-unmentioned elephant in the room. Even as the government hasn’t announced any subsidies for household storage, it’s expediting the development of large-scale storage systems, both public and private.

A number of big projects have already been approved, adding up to many hundreds of megawatt-hours. Of the top five, two (in Pyrgos and Dekelia) are due to be run by the EAC and one (a single approval covering three different centres) by the state-aligned Transmission System Operator. 

“Some might say,” points out Karantonis, “that one reason [storage] isn’t being promoted at the household level is that they’re trying to preserve the market for the central systems, which the EAC itself is moving to establish.”

Indeed, the knowledge that large systems are being prepared (which will obviously help with the issue of curtailment) may be one reason why few are applying for battery storage – though it’s certainly more than before, with businesses in particular showing a marked increase, according to Christofides.

All in all, it looks like the bodies in charge of the current dysfunctional grid will continue to control its development. Meanwhile, on the macro level, the talk is all of the Great Sea Interconnector, and linking up with other countries’ energy systems.

The dream of self-sufficiency seems more utopian than ever.