bernardd wrote:
Why are you talking about an 20 factor?
P = U x I
if you go from 230V to 12V, for the same power the current is 20 times bigger
For 10W it does not play so much, for 100W it's already different.
bernardd wrote:The photovoltaic production is continuous, as the batteries: switch to 230V then back to 12V, it's an excursion with a lot of losses and expensive hardware to power 100 or 200W.
Yes but that's not in the initial post.
And then at the level of the losses that is calculated.
Take the extreme 200W lighting 12V case, enjoy calculating the necessary cable section between the batteries and the point of use to keep a valid voltage arrived at the lamp (normatively one tolerates 2 to 3% of fall of voltage)
Compare the price this cable (and the difficulties to ask it in view of its size) to that of a beast 12V / 230V 200W converter
Finally, evaluate the losses between the efficiency of the converter and the losses due to the joule effect in the cable.
In the end I am not convinced that it is always to the advantage of an installation in 12V.
I confess I did not do the math and I could be wrong, but my intution tells me that I am not far from the truth.
Have fun doing these calculations and show us that I'm wrong.