PV Gap

Lorraine Said:

What does a Solar PV system and plastic surgery have in common?

We Answered:

Both use Silicone

Pedro Said:

how could I evaluate a building requirements to install a Solar PV system ?

We Answered:

It's a major job, and you can spend months doing this.

You need a number on typical and minimum number of hours of direct sunlight on your location.

Decide on either battery storage or power grid storage. The latter is best for any good sized system, but requires permission and cooperation from the Power company.

How much of the building's power will you supply during sunlight hours?

How much during night or cloudy days?

Eventually you come up with a size for the solar array. Now you can calculate size, and find a space to mount them so that they get the optimal amount of sunlight.

If you go with battery, you need storage space, decide on type of battery, type of charger, type of inverter, and how to blend that in with the AC power from the power company.

etc.

Salvador Said:

What is the overall efficiency of a solar PV system?

We Answered:

It would not be unusual for PV panels to be 15% efficient, that is, 15% of the incident energy is turned into electricity. Note that when a PV system is installed on a residence, that system rarely takes up all of the suitable roof space, so efficiency is not an issue, cost is.

In a grid-tied system, 4-7% of the energy from the panels is lost in the various components of the system, mainly the inverter.

In a system using batteries, another 25% may be lost to the inefficiency of charging and discharging the batteries.