How does the domestic battery work?

Firstly, about the technology. Frank Energy has reached agreements with all the home battery suppliers shown on our website about access to the energy management system (EMS) of the battery and about the control we want to apply. Soon we will be able to connect to your home battery via WIFI (or via 4G) and via the supplier's software (API). The commands we can give to your home battery are simple: ‘start charging’, ‘start discharging’ or ‘do nothing’. The technical safety limits are always limited by the software and hardware of the battery, which we cannot cross.

How do we control your battery?

It depends on the situation.

In few words, there are two approaches: self-consumption or commercialisation. And between these approaches, all kinds of combinations are possible

Regarding self-consumption, the algorithm gives priority in the control to the storage and self-consumption of the energy generated by the solar panels. This is an excellent strategy, as it avoids paying taxes on the energy consumed. Our algorithm will soon know approximately what you consume in a day, it will be able to predict what your solar panels will produce tomorrow, thus reserving enough space in the battery to store that generation. In this way, it will keep your meter more or less at zero and minimise your costs.

If you want to commercialise energy, it means looking at how the electricity stored in the battery can be maximised in different energy markets. And there are quite a few. For example, there is the OMIE day-ahead market. This is the market that sets electricity prices each day 24 hours before the following day, and these prices form the basis of our electricity contract.

In turn, there is the deviation market. In this market, the national grid operator (in Spain, Red Eléctrica) acts. Its aim is that market players help to maintain a balance in the national grid. It does this by means of rewards and financial penalties. And as always... Something happens: a bad storm blocks the sun, preventing solar production, or a power plant closes. This series of uncontrollable situations makes the market quite volatile, rewards and punishments alternate rapidly creating high peaks and deeper troughs in electricity prices.

Finally, there is the congestion market. It exists at national and local level. It is the market where grid operators try to resolve bottlenecks when the demand for electricity is very high compared to the supply capacity. They usually ask market players for help. By agreeing with them to purchase or produce small amounts of energy at certain times and/or places. This market is slowly taking off.

In the current default strategy, the operating system uses an intelligent algorithm to minimize your energy costs by managing how and when your battery charges and discharges. Charging is prioritized during periods of low Energy Prices. The system always prefers to use solar energy for charging first. If the available solar energyis not sufficient, the battery will charge from the grid at low prices. This ensures that the battery still charges on days with little or no sunshine. When Energy Prices are high, the battery switches to self-consumption mode, supplying power to your household to avoid drawing expensive electricity from the grid. During periods with unattractive Energy Prices, the battery goes into idle mode. In this state, the battery is not used — it neither charges nor discharges. This is financially beneficial, as it avoids charging when electricity is expensive and preserves the battery for more favorable periods. As a result, your household may temporarily draw energy from the grid during these moments.

This strategy ensures that your battery has sufficient charge for the expensive peak hours, and allows you to inject electricity back into the grid when prices are favorable. By doing so, your electricity meter remains more or less at zero, and your overall consumption costs are minimized. We’re always working to expand our market presence, maximize financial benefits, and support the stability of the energy grid.

In addition, if you authorize Frank Energie to control your battery, you will receive a monthly bonus as a reward.

Do you have questions about our energy contract, our smart services or this website?

Don't hesitate to ask. We want things to be clear and will be happy to explain them to you. Send an email to soporte@frankenergy.es and we will answer your question as soon as possible.

How will your savings and rebates be paid out later?

Your savings and rebates are visible in the app and will simply be paid to you via your regular energy bill.