PV Solar Design Software

Re: PV Solar Design Software

What kind of solar design software are you looking for?

There is predicting the output of a solar array based on local solar irradiation data.

There is software/tools to predict the impact of shading by trees/buildings around a solar installation.

There is solar electric and solar thermal programs to define insulation (ceilings, walls, windows, floors, etc.) of buildings.

Lately there are some neat tools for people on grid to monitor their power consumption over time which can be very interesting. May make more people look at seriously upgrading heating/cooling/insulation/appliances for their homes--always a good thing.

And there are packages to estimate jobs, create parts lists, etc... for commercial installers...

And a lot more that I have not mentioned or even thought about.

While we have a few professionals here that design solar charge controllers/inverters and other commercial folks that do solar installing--for the most part many of us are just interested in solar / conservation and use a few rough tools to estimate solar output and use rules of thumbs to get systems "close enough" for people to be happy with the results.

Solar PV output can vary 10-20% or more year over year due to variations in weather. Add "losses" in power output (from solar panel "marketing rated power output" to actual usable AC 120 VAC power at the outlet) of nearly 50% for off-grid systems (not an "big problem"--more like the facts of life). Also, for off grid systems, they can only store around ~3 days of electrical power cost effectively.

So, getting "exact" numbers is frequently just an exercise in frustration.

Instead, design for 10-20% accuracy starting with knowledge of the loads, apply rules of thumb to get a quick (workable) system design, and ensure there is a backup generator to cover for a week or two of bad weather and/or visiting relatives.

Your thoughts?

-Bill