My career in PV started in 2006. But my background had not been in offgrid solar – I did not start 2019 a big expert in this field, to put it mildly. There was a learning curve. I phoned some of my friends and contacts that have deep first-hand expertise on the subject. And at Intersolar in May I sat down with some of them to discuss my draft designs. That proved very useful.
There were a few issues that I at first did not find intuative. For instance, grid-forming and the art of controlling a diesel-generator. (You may be asking now: why isn’t that diesel-generator simply discarded? Because it shall serve as a backup. A backup for the hopefully rare case that solar and batteries can’t provide enough power.) And I was quite surprised that even in 2019 a lot of the advice I got was to stick with proven lead-acid batteries, as lithium-ion batteries might not last so long in sunny Morocco. But I also learned that specifically the lithium-iron-phosphate type of batteries (LFP for short, or LiFePo4) can cope fairly well with at least some heat. So they appeared (and appear) to be suitable. Some LFP products on the market are actually fully supported for this kind of application. So LFP is what we’ll use!
The design is now practically final with a little bit of give and take regarding the size of the PV arrays. Simulations look pretty solid with 50 to 75 kWp of solar and around 25 to 30 kWh of batteries.
Besides the engineering part, I’m also working on various funding options. The project pays back within less than 3 years, so it should not be too difficult to figure out financing. We will see… Fingers crossed!