Backup box or emergency exit: how to maintain electricity in the event of a power failure

Photovoltaic self-consumption is experiencing exponential growth in Spanish homes and companies, obtaining significant savings on electricity bills while contributing to a sustainable energy model and avoiding the emission of greenhouse gases.However, we must consider what happens in certain scenarios: What do we do in the event of a blackout? Does the photovoltaic installation continue to work?

In emergency situations, you can make use of your backup box to maintain the energy supply in your home.

Today we will talk about what a backup box is and how it works, types and the necessary components for its installation.

It is an alternative system that is implemented in photovoltaic installations to maintain a home with electricity when there is a power cut or blackout.This definition may remind you of solar batteries, but they do not serve the same purpose.

While solar batteries store the energy produced by the solar panels for later use, the emergency system uses the energy stored in the batteries to restart the inverter. This will ensure that we have electricity available in our home in the event of a power failure.

What is the advantage of back-up power?

This device remains fully operational in the event of a power cut, i.e. it is activated to supply us with electricity in such situations. However, a solar battery depends on the inverter and in the event of a power cut, both elements stop working.

Emergency outlets are efficient alternatives to power outages in order to have sufficient energy available. It is important to use them correctly so that they provide the necessary amount of electricity.Always prioritise basic lighting and essential electrical appliances such as a fridge or freezer.

There is not a single emergency equipment but, depending on the photovoltaic system, some alternatives or others will be available. These are the types you can find:

The systems for critical loads supply important devices that remain connected continuously, such as a refrigerator, but are not used for all the electrical appliances in the home, only what is necessary.To supply critical household consumption, there are two different ways.

The first alternative you can use is to install a plug outside the inverter to use it for the necessary loads after a power cut. This is the most recommendable option thanks to its easy installation.

On the other hand, we have the option of dividing the electrical panel into two sections, where one will be used for critical consumption, and the other to supply your usual energy consumption without power cuts.

The full backup system guarantees all the electricity in the home in the event of a blackout. This system is created only for emergencies and to supply the home with energy for a few hours; not uninterruptedly.How to install this device? By means of a switch, automatic or manual, that allows the mains system to be de-energised.

You will have access to electricity up to a maximum of 3 kW, therefore, it is essential to use this amount for the consumption that is just and necessary until the electricity grid returns to normal.

To install this device in your installation with solar panels, you will need a system of meters and relays in the alternating box for correct operation. In addition, it must be disconnected from the electricity grid.This last point is of vital importance because when there are power cuts, a technician will come to repair it and if our system is connected, it could pose a danger by causing a shock that could cause health problems.

How do we avoid this type of accident? The emergency system must be connected to a switch and can be:

Whether you have an installation with solar panels or you are considering switching to self-consumption, it is important to be aware of the possibility of installing an energy backup in the event of a blackout and continue to have electricity in your home without having to do without the use of essential electrical appliances.This process is carried out by means of an alternative system to avoid accidents during power cuts and to maintain the safety of professional technicians at all times.

If you do not yet have an installation for self-consumption in your home, try our savings calculator and find out how much you can reduce your electricity bill month by month.