Saving tips for a home battery for solar panels

In our example, a plug-in battery of 2,5 kWh can complete 200 full cycles. With it you store 500 kWh and, after the storage loss, get 450 kWh back. Own consumption then rises from 30 to about 45 percent.

A 6 kWh battery only needs to complete about 167 full cycles to store 1.000 kWh. That already reaches the limit of 60 percent own consumption. A 10 or 15 kWh battery can store more on sunny days, but is more often partly empty during the rest of the year. With the same solar panels and the same household consumption, that larger capacity therefore yields no extra annual saving in our base scenario. The larger capacity only makes the home battery more expensive and will needlessly extend the payback period.

These values only apply to the data we used. With more solar panels, a heat pump, an electric car or a different consumption pattern, a larger battery can indeed process more energy. With a small solar roof or a home that already uses a lot of electricity during the day, the extra storage actually turns out lower.

Up to and including 31 December 2026 you can net meter solar power. Storing a kilowatt hour therefore does not in itself yield any price advantage. Due to the storage loss, your netted quantity even becomes slightly smaller. In 2026, however, a battery can prevent feed-in charges. The CBS calculated in January 2026 with an average of € 0,126 in feed-in charges per kWh fed back.

With a plug-in battery, the feed-in in our example drops by 500 kWh. That theoretically avoids 500 × € 0,126 = € 63 in feed-in charges. From that, € 13,50 is deducted due to 50 kWh of storage loss at € 0,27 per kWh. The net saving thus becomes about € 50 per year.

With the larger batteries, the feed-in drops by 1.000 kWh. The avoided costs are then € 126. The storage loss of 100 kWh costs € 27, leaving about € 99. In reality, many suppliers work with tariff bands. If you stay in the same band after installation, the saving can turn out much lower or even negative.

From 1 January 2027 the net metering scheme ends. Solar power you use yourself then avoids the full consumption price, while feeding back only yields a fee. For this scenario we use the calculation values of Milieu Centraal and Vereniging Eigen Huis: € 0,21 per kWh consumed from the grid and a net feed-in value of € 0,005 per kWh after feed-in charges. With a plug-in battery you avoid purchasing 450 kWh: 450 × € 0,21 = € 94,50.

At the same time, you miss out on the fee for 500 kWh: 500 × € 0,005 = € 2,50. The annual saving therefore amounts to about € 92. A well-matched 6 kWh battery delivers 900 kWh to the home. The calculation then becomes 900 × € 0,21 minus 1.000 × € 0,005 = € 184 per year. A 10 or 15 kWh battery in the same average household likewise stays at around € 184, because the available solar power and the evening consumption are the limiting factors.

For the purchase prices we use average calculation prices within the current market ranges. According to Vereniging Eigen Huis, a plug-in battery of 2 kWh costs about € 500 to € 1.000. For 2,5 kWh we calculate with € 900. The Consumentenbond gives € 4.000 to € 6.000 for an average fixed system, including installation and VAT. For 10 and 15 kWh we use the middle of the market ranges that Zonneplan published in 2026.

According to the Consumentenbond, a home battery lasts on average about fifteen years. To show the real annual return, we therefore spread the purchase price over fifteen years. Maintenance, financing costs, subscriptions, capacity loss and a defect outside the warranty have not been included.

The return in the table is the annual saving divided by the purchase price. It is therefore a simple return without interest, maintenance or depreciation in value. The column on the far right also deducts the average annual depreciation from the saving. You can see that a higher capacity actually yields a lower return in this scenario.

Note: above we assume that the plug-in battery also lasts fifteen years. However, there are large differences in quality. With a shorter lifespan, the calculated surplus disappears entirely or partly.

In the scenario without net metering, only the small plug-in battery pays for itself within the average lifespan. With € 92 annual saving, it takes about € 900 ÷ € 92 = 9,8 years. Over fifteen years, the total saving amounts to about € 1.380. After deducting the purchase price, about € 480 remains. That is not a high return compared with that of other energy-saving measures. Insulating is often more interesting.

For a fixed 6 kWh battery, the simple payback period is well over 27 years. Over fifteen years you save about 15 × € 184 = € 2.760, while the purchase price is € 5.000. You then still fall € 2.240 short. With 10 kWh that shortfall rises to about € 3.740 and with 15 kWh to about € 6.990. With too high a capacity, you do not earn back the purchase price within the average lifespan in this scenario. That shows that correct sizing is essential.

This is of course not a prediction for every home. Electricity prices, feed-in fees, feed-in charges, battery prices and warranty conditions can change. The location and size of your solar panels, shade, your consumption per hour and the available battery capacity also determine how many cycles you actually achieve.

By not only storing your own electricity, but also working with the margins within a dynamic energy contract, you can in turn increase the return. However, do not simply add this dynamic saving to the saving from storing solar power. Both applications use the same battery capacity, and extra cycles cause more wear.