CIGS idea for solar on boat, opinions?

I have the other thread about electric propulsion on our sailboat, which is wired and ready for the motor to arrive.

Some discussion about our initial decision to not install solar has me reconsidering it.

The boat is not large (17 foot sailboat) but will be likely towing a Portland Pudgy dinghy (unsinkable, sort of a rotomolded thingy)

I am now thinking that if we do add solar, it would be best to not have it fixed anywhere, but rather as portable and stowable as possible.

This has me looking at the BougeRV CIGS panels, perhaps the 200 watt version, which is about 83 inches by 27 inches. One option would be to sew two of these on to a piece of Sunbrella fabric with some ultra reinforced stainless steel grommets in the fabric, to create sort of a solar tarp that is 86" x 57" inches or thereabouts. We could then drape this over the dinghy with some lashing, or toss it on the foredeck when not actively sailing, or even put it on a boom tent for when moored somewhere during the day without access to shore power. The whole thing could roll up into a 30 inch tall, 16 inch diameter bundle which we could just lash to the transom or toss in the bilge. Perhaps we could even hank this thing on to the forestay and put a halyard on it, lift it up like a DIY solar sail of sorts for windless days where the sun is low. The flexibility and durability of the CIGS seem like they could handle this type of abuse.

The considerations:

1) How do we get the right voltages for our system. The open circuit voltage of the 200 watt panel is around 30V. Thus two in series is 60V and I am thinking this is not enough overhead for a 48V lithium bank, which needs 56 volts or so for charging. There are not very many boost charge controllers, none in blue that I know of. Should we consider THREE 200 watt panels? The fabric idea starts to get a bit large at 86" x 84" and might not fit on the foredeck or across the dinghy. Alternatively, the 100 watt panels are 83" x 14" and have a open circuit voltage of the same 30 volts, so three would be 90V which is plenty of overhead for a 48V bank. The downside here is 300 watts is not a lot. Might only expect an average of 210 watts for 6 hours, or 1230 watt-hr a day from 300 watts of panels, vs maybe 1680 watt-hr per day for the 400 watts of panels (just my guestimates here, although the CIGS is supposed to be really good for shading and such).

The other idea is use 6 of the 100 watt panels and make two of the fabrics, 86" x 50" and wire them series parallel, still giving you 90V. Now you have added quite a bit of extra connectors and wire vs using two or three of the 200 watt panels in one fabric.

Thoughts?

This is the typical power and voltage range for boost chargers for the emobility market. The application there is to charge a 36 to 60V traction battery

Sure, the quality is worse than blue, but the options are out there and there probably are some designs that have delivered a lot of miles for the e-bike etc crowd

I don't remember what it is called, but there is a device that sort of looks like a small torpedo with a propeller. You tow it behind your sail boat and it generated power - sort of like an alternator. ( when sailing obviously )

If you are already towing one small boat, then maybe towing a second just for power makes sense?

HarryN said:

I don't remember what it is called, but there is a device that sort of looks like a small torpedo with a propeller. You tow it behind your sail boat and it generated power - sort of like an alternator. ( when sailing obviously )

If you are already towing one small boat, then maybe towing a second just for power makes sense?

Click to expand...

Technically our Navy 6 can also do hydro generation (with their battery of course) but the maths don't work so well for our 4 to 5kt speed. Plus there are sections of the loop where we can't sail, so towing a generator while motoring with an electric is kind of a net negative energy system unless you are on certain forums.

IGBT said:

Technically our Navy 6 can also do hydro generation (with their battery of course) but the maths don't work so well for our 4 to 5kt speed.

Click to expand...

The math don't work well, but I expect to have your real tests and data soon

Thanks.

Obviously those perpetual motion ideas are troublesome.

What I had meant in terms of towing is that you are already pulling one small boat / unsinkable behind you for safety. I don't know how much room is on it.

In theory at least, something additional could be towed for power - such as solar and batteries to be more nimble and roomy in the sailboat.

As far as solar charge controller, this company was started by a guy who likes to sail and the controllers are optimized for it.


I have used them in a van with a 48 volt pack. They work a bit better if the controller is mounted on something to dissipate the heat such as angle aluminum, even though they don't require it.

HarryN said:

Thanks.

Obviously those perpetual motion ideas are troublesome.

What I had meant in terms of towing is that you are already pulling one small boat / unsinkable behind you for safety. I don't know how much room is on it.

In theory at least, something additional could be towed for power - such as solar and batteries to be more nimble and roomy in the sailboat.

As far as solar charge controller, this company was started by a guy who likes to sail and the controllers are optimized for it.

Genasun – Sunforge LLC

sunforgellc.com

I have used them in a van with a 48 volt pack. They work a bit better if the controller is mounted on something to dissipate the heat such as angle aluminum, even though they don't require it.

Click to expand...

Sorry I get what you meant now.

I am still up in the air on actually bringing the Pudgy dinghy. It is a fair bit of drag I think, although I don't have test numbers yet. When our motor gets here I plan on some trips to the local lake to see what wattage is needed to drag it around at 4 kts vs not having it and also how much it slows us down while sailing. It would be nice to have, and I guess a little safer...tiny bit safer...if we hit a barge at 12mph on the Mississippi we are probably dead no matter what dinghy we have.

Was thinking about the 600 watts of CIGS panels on a boom tent and then had the thought that it might be possible to double that when our mast is down. Because we are doing the loop which has sections of low clearance, we are going to carry a mast crutch that just attaches to the side of the rudder mount. With a matching crutch in the bow, we can lower our mast to horizontal in a few minutes.

I wonder you could extend the panel area to cover the entire 17 foot length of the boat when the mast is in this horizontal position? You would need some sort of flexible poles that could bend around the mast and lash to both sides of the sailboat and then a fabric or something to go over this which would help support the lightweight but rather floppy 7 pound CIGs 200 watt panels, which are 27" x 86".

I think you could get 1200 watts of solar in this fashion, which is a lot for a 17 foot boat. That would charge up the 10kWh bank in 2 days?

A pic of your boat may help. Are you doing the great loop?

I think a dingy mounted solution will be misery.

Is it possible to mount a panel as a shade bimini?

Edit-never mind. I see the other thread

We use this one a sailer boat to connect the solar panel on a railing

Here is dutch forum for Sailors .
Use Google Chrome and select Translate if you like to read it.
But thare a lot.of picture how people have a setup from solar panels on thare boat

Bluedog225 said:

A pic of your boat may help. Are you doing the great loop?

I think a dingy mounted solution will be misery.

Is it possible to mount a panel as a shade bimini?

Click to expand...

Yes, we are planning to do the great loop on a 2013 Montgomery 17 sailboat with a 10kWh LFP bank and a ePropulsion Navy 6 (6kw) motor. Testing indicates 4kt speed at 500 watts input to the motor, for technically 80nm range on one charge (flat water, no current). Going against current in the section up the Ohio, I imagine we will be running 2000 to 3000 watts and only moving at net 2 kts, especially around the Olmsted locks, but you kind of want to get through there and out of the way of the HUGE barges.

We are thinking a shade boom tent...can't really do much paneling with the main up though, because there is just no room. You can motor though with the main down and a boom tent up.

This is the boat: