[tonyarkles]

> It's not mysterious, it's that thermal convection is much stronger when the panels are vertical

I agree that, when you factor in semiconductor physics, it's not a mystery but it isn't necessarily an intuitive result for most. I've been working in aerospace for 5 years and one of the things that has been very clear to me is that peoples' intuition about things breaks down very quickly when there's non-linear factors involved in an analysis. In aero it's primarily square-law/cube-law tradeoffs; in semiconductor physics it'll be more exponential.

For this particular problem you've got an exponential (semiconductor behaviour as a function of temperature) multiplied by a trig function/dot product (cosine of the angle of the sun relative to the normal of the solar panel), with a bit of natural thermal convection thrown in for good measure. Modelling this (digital twin, as they call it) is feasible but it's not something most people are going to have a good intuition on with respect to where the sweet spot is going to be.

[schiffern]

The cited "digital twin" software[0] doesn't model convection (it just uses wind speed and an empirical factor), which is why it gives a higher predicted temperature than the physical model.

[0] https://www.sciencedirect.com/science/article/pii/S187661021...

[dboreham]

If you run PV/battery systems you pretty soon notice that in extreme cold events the controller can shut down charging because panel output becomes so high that the batteries will be overcharged.

[jacquesm]

The air near the top is 100% trapped, there is no way for it to escape and it's the hottest air under the panel. Overlap with the cells is anywhere from 1/2" to 1.5" so that's a sizeable fraction of the cells. Probably close to 25 to 30% or so.

[CyberDildonics]

The average person's intuition and 'mysterious' are two different things. One is someone with no knowledge assuming the wrong thing, the other is experts not able to figure something out.