A flexible small producer of renewable energy

Solar park combined with batteries

The goal of a flexible small producer is to sell the produced renewable energy at a maximum price. The stock market price of electricity is usually highest in the morning and evening hours, while solar production is at its maximum at midday.

If the price difference between daytime and morning/evening hours is large, it is more profitable to store the produced solar energy first in the battery and then supply it to the grid later at a higher price.

In winter, when solar energy production is minimal, the battery can be charged from the electricity grid during the cheapest hours and returned to the grid during the most expensive hours. It also allows you to earn money with the battery during the winter.

It is reasonable to choose 2-3 times the capacity of the solar park as a suitable battery capacity. For example, a battery solution with a capacity of 100-168 kWh would be suitable for a 50kW park. The capacity of the battery should be equal to the capacity of the park.

Battery payback time

The payback period of the batteries depends primarily on the intraday volatility of the electricity exchange price. For example, the average intraday price volatility in 2022, or the difference between the min and max price, was 0.24 EUR/kWh.

In order to achieve a short payback period, smart management of the batteries, which takes into account both electricity stock exchange prices and weather forecasts, is of primary importance. Based on this, we estimate the payback period of the batteries to be 7-9 years, of course it must be taken into account that this is based on the assumption that the intraday volatility of the stock market price will continue to be of the same order of magnitude.