How much sun are you getting cruising?

[offgridcrazy]

I'm just getting on the water full time. I've got a 8'6" x 32' flat area to use for panels. I'm going to be following the Great Loop so I'll be in the gulf and around Florida in winter and in the Great Lakes in the summer, I'm on a tight budget and wondering how much value I'll expect to get for the cost of making the panels adjustable to move them to get a better angle to the sun through the day, or just let them be flat and not worry about the low solar input through 2/3rds of the day? Also I think I'm going to be using some bifacial panels I've found, about 1/2 of them will be over a white roof and 1/2 will be about 7' foot above the front deck like a shade cover so they should get good reflection off the water ( so much as the water I'm in is reflective and not too stained or shaded from near trees in narrow rivers I dip into explore )

 

[FilterGuy]

On a boat (or any mobile system), the biggest issue is shading. It is not just shading from the shore. Even an antenna whip can dramatically impact production. What makes this difficult to deal with on a mobile install is that at any given time the shading problem can be different. You can't even know which way north is going to be. Consequently, I would invest in minimizing the shading impact before I spent money/effort on tilt frames. It sounds like you will have two areas of arrays. Presumably, there will be two MPPTs. However, it might be wise to have multiple MPPTs for each area. That way, you will be less impacted by a small patch of shade cutting production on the whole array.

Another approach is to use something like the Tigo Optimizers. This can be expensive but it effectively puts a dedicated MPPT on each panel.

BTW: with modern panels that have two or three integrated bypass panels, the shading issue may be less severe, but I would still be careful with the layout and wiring to minimize shading issues on one panel impacting a lot of panels.

 

[Mark Halvorson]

Shading is a huge issue. Even bird poop, can drop my solar production a lot. I have 6 solarever 455 in one array and 4 in another array. All are mounted flat. As on a boat trying to guess how to tilt them every day is not worth it. One bird poop on the six panel array, can cost me 700 to 1kw loss.

The best way is to get separate solar controllers for each panel, or the Tigo optimizers for each. About same cost.