Hello /diy/,
I've been thinking for a while about installing some solar panels in my boat (32ft) as a back up/sustitute to the twin 12V batteries I'm using now to run it.
I would like to know if anyone has experience in this kind of setup, as I would like to build it from scratch and some tips on the matter would be appreciated.
>>994844
They don't substitute the batteries, they charge them.
If you haven't done the slightest bit of self research into the subject, then fuck off. That's as much as I'm helping.
> I would like to build it from scratch
>>994847
Pretty much sums it up.
Should also be pointed out that if you fuck up and use a bad charge controller you might turn your battery bank into a bomb.
Unless you have experience with these types of systems you might want to consider buying instead of building.
>>994844
It would only be practical to have the cells charge the batteries, as someone else already noted.
You would need a LOT of cells to get rid of the batteries totally--or even just to run a couple hundred watts of stuff without the batteries.
Solar cells are best thought of as an extremely current-limited voltage generator. As you draw increasing amounts of current from them, the voltage that they can supply drops down drastically.
Solar charge controllers are made to draw only a small amount of current, to ensure that the panel voltage stays high enough to work properly.
Making your own panels:
If you want something mounted outside and durable over the long-term, this is usually a poor idea.
The reason is that moisture tends to accumulate inside the panel enclosures and corrode all the metal parts of the cells and interconnects.
Home-made panels only work well in desert/arid environments, where there is very little humidity.
Factory-made panels are sealed in a way that greatly prevents this problem, and duplicating the method at home is usually impractical (vacuum + oven sealing; it requires a BIG oven to do. factory panels are made on tempered glass and sealed with a plastic called Tedlar).
If you ABSOLUTELY INSIST on making your own panels:
On the China sites they sell encapsulated mini-panels now, that are a small panel of a standard voltage (5v, 6v, 12v or 18v I've seen) and that are encapsulated in epoxy resin already.
You still have to solder panels together since one panel doesn't put out much current, but at least using these panels would greatly decrease your points of possible failure (due to corrosion).
If you want maximum power: get something with monocrystalline or polycrystalline cells.
The amorphous and flexible-rubber cells may cost less but they don't put out as much power.
>>994879
>factory panels are made on tempered glass and sealed with a plastic called Tedlar
I was going to say that tempered glass has to be bought already cut to size, because you can't cut it yourself.
I see now that there are various people on the internet claiming that they can do this however.
I would consider this method highly unreliable....
The unique property of tempered glass is that it has thermal stresses left in it such that it is harder initially, but that if it is cracked at all, the cracks tend to propagate themselves.
The problem with cutting tempered glass yourself is that if you have made ANY microscopic cracks in it while you cut or snapped it,,,,,,, it is a pretty good bet that those cracks are eventually going to spread (and fan out) on their own. It may take a week, maybe a month, maybe a year--but it's going to happen.
If you want to try cutting tempered glass on your own and don't mind the glass failing catastrophically at some [random] point in the future, go ahead and try cutting it yourself. (--or if you just have a piece of unwanted tempered glass and want to see what happens. wrecking stuff *can* be educational--)
If you want the glass to not fail, go to a glass shop and order a piece in the size you need. It will cost money and is not DIY, but it will probably NOT break like it's supposed to.
>>994888
Or just make the solar panel to be the size that the piece of tempered glass happens to be.
>>994847
>not knowing about solar systems that don't use batteries, used to run entire homes
>>994858
This shit is legos now, kid. Not difficult in the slightest.
Solar installer here. 255W industry standard panels are 3'3"x5'5", only produce 7 amps each, and are not cheap. After your non-chink charge controller or inverter you're better off using your current system. If you can afford a 32' boat i think you can handle some extra batteries. Do you never use your boat when it's cloudy or dark?
>>994844
PV system design engineer here.
DC systems are pretty simple. Grab a multimeter and a stopwatch and figure out how much power you're using, then buy PV panels accordingly. Then get a quality charge controller and a DC disco and wire that shit up to code senpai. NEC 2014 isn't completely terrible except for one glaring safety issue, I can't think of the exact section but I remember it has to do with pants on head retarded grounding requirements.
If you're not experienced with this, youtube or google will hold your hand.
>>995759
And yeah, panels are gonna cost you about $1/Watt. Ain't cheap but a good investment IMO.
Literally, just get a few extra batteries and a solar trickle charger.
>>994947
You mean the ones that dump the excess power into the grid, effectively treating it as a giant battery?
