How to choose the right inverter for my isolated solar installation?

It is important to bear in mind that for limited light consumption or other small consumption in direct voltage, such as mobile phone chargers or tablets, the use of power inverters is not mandatory, there are currently many lighting options at 12V or 24V and also chargers like the ones we use in our cars.

Current inverters transform electricity at 12, 24 or 48Vdc stored in batteries, into electricity at 230Vac (like the one offered by an electric company in our homes).

Modified wave inverter or sine wave inverter

For the use of some electronic equipment such as some televisions, stereos, laptops or phone chargers, the use of a modified wave inverter is sufficient; But for other appliances such as refrigerators, washing machines, microwaves, water pumps and more and more modern electronic equipment, the use of a pure sine wave inverter is necessary.

Due to the existence of more and more electronics in all modern equipment and appliances or even LED lighting, it is increasingly important to use a pure sine wave inverter for the correct operation of equipment or appliances and to guarantee their durability and achieve their long useful life.

We always recommend purchasing a pure sine wave inverter, as this way we avoid possible problems.

Inverter or inverter-charger

On the other hand, we also have to take into account that in installations where it cannot be guaranteed that all the energy necessary for the supply with the solar panels will be generated, or where there is higher consumption on a timely basis, it is advisable to use an inverter. -charger in order to be able to add a generator set to support the installation, which at the same time as supplying energy to consumption, can be used to charge batteries through the inverter charger.

To determine the inverter that we need, basically we have to be clear about the power that we will need available, that is, if we had to request a supply from the electrical network, the power that we will need is the one that we would hire from the supplier, because that power is what we have to choose from our investor. Keep in mind that if we need, for example, 3kW frequently, it is advisable to choose an inverter that can give more than 3 kW since the power that the manufacturer says that an inverter gives is in laboratory conditions and therefore at less than 25ºC of ambient temperature. , but as soon as there is a higher ambient temperature or if the equipment or the cooling system (fans and/or radiators) are dirty, the inverter will be able to give less power without stopping due to temperature.

Inverter at 12, 24 or 48 V

Another issue to take into account is the battery system we have, whether it is 12, 24 or 48V, since the inverters only work with a single input voltage. In addition, the more power we need available, the recommendation is that the battery system works at a higher voltage, so that less amps of consumption are needed and the losses in the cables and in the system as a whole are lower. Although there are more and more powerful inverters for all available voltages, as a general rule at 12V inverters of up to 2,000-3,000W are recommended, for 24V up to 5,000-6,000W and for 48V all kinds of solutions can already be found up to very high powers.