Do energy storages already pay off?
Most photovoltaic owners in Łódź and the surrounding area ask themselves the same question: is it worth spending another several thousand on a battery? At Polish Wings of Development we don't like fluff, so we took a calculator and checked the data from the 47 most recent installations. The results clearly show that the time of thoughtlessly returning electricity to the grid for pennies is slowly ending.
No more giving away electricity for pennies
The current settlement system, i.e., net-billing, is not kind to those who produce a lot of energy at noon when no one is home. You then sell electricity to the grid at the average market price, which on sunny days can drop to even 0.22 PLN per kilowatt-hour. However, when you return from work at 6:00 PM and turn on the induction and laundry, you buy back that same electricity from the utility for about 1.16 PLN. This difference is a pure loss that you see in your wallets every day.
Energy storage allows you to keep that cheap electricity for yourself. Instead of sending the surplus to the grid for pennies, you charge your own battery. In the evening, when the sun no longer shines, you use your own supplies. Thanks to this, you realistically increase so-called self-consumption from a typical 23% to as much as 67%. This means that you cover more than half of your electricity demand from your own roof, without asking for anything from the PGE power plant or another supplier.
At Polish Wings of Development we monitor the systems at our clients' homes and see that with a well-selected 10 kWh storage, a family of four is able to almost completely eliminate energy purchases from April to September. These are not pipe dreams, but hard data from meters that we check every month in our office on Piotrkowska.
Every kilowatt-hour left at home is 84 grosze of savings compared to electricity purchased from the grid.
Real costs and the Mój Prąd 6.0 grant
Let's get to the specifics, because they hurt the most. A good energy storage with a capacity of 10-11 kWh is an expense of 24,300 - 28,600 PLN including installation. That's a lot of money, but here the state comes into play. As part of the Mój Prąd 6.0 program, you can recover up to 16,000 PLN for the storage itself, as long as you already have photovoltaics or are installing them at the same time. This changes the situation because the real cost of the investment drops to about 11,000 PLN.
Many people are afraid of the paperwork related to grants. In Łódź and the Łódź region, we have already helped 83 clients go through this process without a single error in the documentation. The truth is that without a grant, the return on investment would be about 11-13 years, which is unacceptable for many. With the grant, this time is shortened to 6-7 years, which with a battery warranty usually lasting 10 years, gives us at least 3-4 years of pure profit.
It's also worth mentioning the thermo-modernization relief. What the grant doesn't cover, you can deduct from income tax (PIT). At a 12% tax rate, you will recover another 1,320 PLN from the amount of 11,000 PLN during your annual settlement with the tax office. Finally, the storage costs you as much as a used city car, and it works for itself every day as soon as the sun rises.
Will the battery stand the test of time?
The biggest myth we hear during meetings in our accelerator is the one about batteries dying after 3 years. That's nonsense. Modern lithium-iron-phosphate (LiFePO4) cells have a lifespan calculated at about 5200 charging cycles. What does this mean in practice? Even if you charge and discharge the storage every day, after 14 years its capacity will drop to about 78% of the initial value. It will still work, it will just hold slightly less electricity.
(By the way, most people install batteries that are too large, which extends the payback by another 3 years because they pay for capacity they will never use). We at Polish Wings of Development always select the size of the storage based on actual consumption from the last 11 months. If you use 4000 kWh per year, you don't need a 20 kWh battery. That would be throwing money down the drain.
Safety is also important. Modern systems have built-in BMS modules that watch the temperature of each cell individually. The risk of fire in the case of LiFePO4 technology is minimal, much lower than in the old generation of batteries in laptops or phones. We install these devices in the garages or basements of our clients and after 2 years since the first installations we haven't had a single failure requiring equipment replacement.
A LiFePO4 battery after 14 years of operation still retains over 78% of its factory capacity.
For whom does it simply pay off?
Energy storage is not for everyone. If your electricity bills are 120 PLN a month, then forget it – the investment will never pay off. But if you pay over 380 PLN a month, have a heat pump, air conditioning or charge a plug-in hybrid in the garage, then the situation looks completely different. Then the storage becomes the heart of the home, which manages energy so that you don't give a penny to PGE for free.
We operate on hard data: in 2023, our clients with storage saved an average of 2,400 PLN more than those with only panels. With rising electricity distribution prices, this amount will be even higher in 2025. It simply pays off for those who realistically consume energy in the evening and morning hours, i.e., most working families.
To sum up: if you have spare funds, qualify for a grant and want peace of mind with the next electricity price hikes, energy storage is currently the most sensible step in GreenTech. Don't wait until the grants run out, because the call in Mój Prąd 6.0 has limited funds and they usually disappear faster than expected. Let's check the specific numbers for your home before you make a decision.
