But series really is **not** a good idea if there's a chance of partial shading. As in a leaf, twig or bird poop dramatically reducing power output.
Ideal for that is a cheap but solid controller like Victron 75/15, paired 1:1 with a 25-50V panel of the right size under 300 watts. Ideally Sunpower cells, which I believe is what Renology uses.
If you get another panel, get another controller, well under $100.
If you're placing panels out in the sun away from the van, moving as needed, keeping them clean, then series is good for reducing wiring gauge needed for long runs.
Nice thing about Victron is their high tolerance specs allow for a lot of flexibility, can often go series if you like, then later on change to parallel without having to go to another controller.
To me that's worth more than the extra 10-15% you might get from the fact they're MPPT.
And the extra logging / monitoring you get with the dongle later on's pretty cool.
They're also pretty bulletproof, widely used at sea.
Ideal for that is a cheap but solid controller like Victron 75/15, paired 1:1 with a 25-50V panel of the right size under 300 watts. Ideally Sunpower cells, which I believe is what Renology uses.
If you get another panel, get another controller, well under $100.
If you're placing panels out in the sun away from the van, moving as needed, keeping them clean, then series is good for reducing wiring gauge needed for long runs.
Nice thing about Victron is their high tolerance specs allow for a lot of flexibility, can often go series if you like, then later on change to parallel without having to go to another controller.
To me that's worth more than the extra 10-15% you might get from the fact they're MPPT.
And the extra logging / monitoring you get with the dongle later on's pretty cool.
They're also pretty bulletproof, widely used at sea.