What do I miss out on if I don't choose a battery for my solar panels?

If you install solar panels without a battery, you miss out on more than just power in the evening. You also forgo the opportunity for higher savings, greater self-sufficiency, income via grid balancing – and security in case of power outages.

What do you lose without a battery?

1. Lower self-consumption = less savings

Without a battery, you typically only use 30–40% of the electricity your system produces. The rest is sent back to the grid, where you get a lower price – often around DKK 1/kWh, as opposed to the DKK 2.5/kWh you pay to buy electricity. With a battery, self-consumption increases to 70–80%, making your investment more profitable.

2. No power in the evening and at night

Solar panels only produce during daylight hours. Without a battery, you are therefore still dependent on buying electricity in the evening – precisely when the price is often highest. With a battery, you can store the day's surplus and use it at night.

3. No access to grid balancing and flexible electricity trading

Batteries provide access to grid balancing schemes, where you can get paid for supporting the stability of the electricity grid. This can generate annual revenues of DKK 3,000–5,000 – something you miss out on without a battery.

4. No backup during power outages

A solar panel system without a battery and off-grid function cannot supply power if the grid goes down – even if the sun is shining. This is due to safety regulations in the inverter, which shuts down during a grid failure. A battery system with a backup function (off-grid or hybrid), on the other hand, can keep the power running to selected devices in the home.

5. Longer payback period and less flexibility

A system without a battery is cheaper to establish, but the lower annual savings also mean that you have to wait longer to earn back your investment. In practice, the battery often pays for itself faster because it increases both savings and income.

Comparison – with vs. without battery

Calculation based on annual electricity consumption of 8,000 kWh, electricity price DKK 2.5/kWh, and a 10 kWh solar panel system.

Conclusion

A battery is not just a luxury – it is a key component in a modern, flexible, and future-proof energy solution. Without a battery, you get less out of your electricity, no backup, and fewer opportunities to earn money from your system. At EcoRay, we recommend a battery to most people because it enhances the investment and provides the freedom and security that many actually want – but often don't realize they are missing out on.