LeLab SOLAR23 : Off-Grid Solar System Calculator


We can help you find the right solution to your needs.

LeLab is for anyone wishing to design and size an autonomous low power solar photovoltaic system. The sizing of an offgrid system depends on 4 factors : (1) the geographical location of the installation and (2) the daily electricity consumption. The parameters of the system must then be chosen (3), such as the production margin or the autonomy in order to be prepared for days with little sunshine. Finally the choice of solar panel. (4) and the presence or not of a power generator enable the inverter, the adequate charge controller and of course the number of solar panels to be installed, to be determined.


Solar Exposure

You must indicate the location of your installation in order to determine the amount of electricity the solar panels can produce.

Seasonal Loads : (Pro. version only)



Daily electricity consumption can be obtained by adding together the consumption of all electrical appliances.



The autonomy you need must then be selected, i.e the number of days during which your batteries need not be recharged.

Autonomy :

And finally, the system voltage, the depth of discharge of the batteries and the production margin must all be chosen.

Voltage :
Depth of discharge :
Margin :


Finally, choose a solar panel. The number of panels needed depends on the power.

The presence of a diesel generator enables a smaller number of solar panels to be used by supplying energy during periods with little sunshine.



Morningstar TriStar
Victron Energy Multiplus