Half cell solar panels + boom

[ryanroberts]

These look like incredibly good value, and I can fit 2x on my pilothouse with a few inches under the boom. Much neater than messing around with side rails and significantly cheaper and better looking than an arch. Does anyone have any experience with a similar setup? What kind of losses am I looking at?

320W JA All Black Solar Panel - Half Cell Mono Percium - Latest Tech - MCS Approved

 

[Pete7]

Looked at those before buying a single 300w panel from Perlight. Looks very similar but not half cells. Whether you choose the half cells or not (similar output) I think is less important than choosing 60 or 72 cell panels rather than 36, which will have a higher voltage (V) and lower Amp (A) output. This gives the MPPT something to work with, remembering Victron MPPTs required 5v over battery V to start working. Also since the V is higher and the A lower, you can use thinner wiring from panel to MPPT which I did. there is a calculator half way down this page which is worth playing around with:

Cable sizing and selection | 12 volt planet

Note, you may need a different sized cable from MPPT to the batteries depending on the output of the MPPT.

The price of large solar panels is ridiculously cheap at the moment, so I certainly think buying a pair of big panels is worth it. Will they last 25 years? no idea but if they last 10, then I will consider I have got my monies worth.

Pete

 

[GHA]

This gives the MPPT something to work with, remembering Victron MPPTs required 5v over battery V to start working.

Red herring that one, a 36 cell panel with 12v batt bank will easily get the open circuit voltage high enough to start the smartsolar long before there is enough light to do anything useful charging the batteries. Measured it But can't find the link, was just a few minutes after dawn when the regulator turned on.

Edit - found it, even with the mains charger on float the victron still turned on very early - this was in March >