Our design process will follow those 7 steps:

1. Load assessment2. Estimating PV array required energy output

3. Estimating PV array power output

4. PV array configuration

5. Controller selection

6. Designing battery storage bank

7. Inverter selection

The first goal in sizing a PV array, is to estimate the energy that should be produced to cover the need despite various losses.

PV array energy output estimate goes in 2 steps:

• First, referring to the load profile of the site, the share of energy that will be supplied from the PV array is determined.
• Then, we have to de-rate energy needs to account for various losses. In doing so, we want to estimate the minimum energy that the PV array is expected to deliver such as losses in the wiring, battery bank and inverter do not affect the demand. As you can guess, losses come from efficiency of system components. The combined efficiency of the charge controller, battery and cables is 85% while inverter is supposed to have an efficiency of 90%.