Embedding Solar Cells

[jeanathon]

Here is the challenge for those of you willing to accept it.
I would like to not only build custom solar panels, but embed them to the topsides.
Most of you will have seen bartops or table tops that have had things like sea shells or photos embedded into the top with epoxy. This is the sort of thing I would like to do with solar cells. I have done bar tops, but the epoxy for that will not stand up to UV. ie it turns milky. Do any of you know something similar I could use to both protect the cell from moderate weight, UV, and water proof it?
Just think we could revolutionize a small subset of a small subset of the population!

[nimblemotors]

A good reason not to do what you suggest is you can't upgrade them when a better one becomes available in the future.

[Ryan H]

Any worries about keeping the cells from overheating? Plus you'd have to experiment with various UV resistant clear coats and see how that'll effect the cells efficiency. Its probably doable but it'll take a good amount of experimenting. Why not get a grab bag of B quality solar cells from online and try a few tests?

[msponer]

A few years ago "Dow Sylgard 184" was the bees knees for encapsulating individual cells in a panel. I do not know if the state of the art has moved on, and folks are using something else. Dow only sells it in giant drums, so individuals can get a smaller quantity through resellers on Ebay and Amazon.

Please post photos of whatever you make. It sounds interesting.

[jeanathon]

The Dow Sylgard seems closest to what I have been looking for. I have not been able to find out if it is will support moderate weight (me) if applied thick enough. It has given me something to go on though. I will keep you all posted although I am only in the planning stages at the moment.
Keep the suggestions coming.

[seandepagnier]

Originally Posted by nimblemotors

A good reason not to do what you suggest is you can't upgrade them when a better one becomes available in the future.

You should never get a hard drive or computer either because better ones will become available in the future.


I think glass would be ideal if you do not need to walk on the deck. There is no reason you couldn't design a boat so that you don't have to walk on it. At least don't need to walk on most of it. Another possibility is to support it so you can walk on the glass, and use the type of glass with bumps so it isn't as slippery. This would weigh a lot more.

Or maybe just make it slippery but have spots which don't have solar panels which grip good for stepping on these places.. but you could step on the glass as well.

This is going to make the boat very hot inside. Ideally you would have some insulation, or an air gap between the panels and the inside, and are being able to flow between.

Then there are various plastics. There are types which are good for traction, and could go on top of glass and be replaced after going yellow, keeping the glass and solar cells intact.

Maybe start out covering exposed area on the mast and boom as this is quite a lot and doesn't really compromise anything.

[jeanathon]

Edit: Oops just realized I typed topsides when I meant the deck.

For certain I am planning on embedding these in the top of the hatch and hatch cover as well as the top of the lazaret locker, but wouldn't it be nice to be able to use all the deck space.
Covering the mast is an interesting idea. I know on land vertically mounted solar cells are not very efficient, but perhaps with the increased reflection from the water this might be viable. Hmm.

[seandepagnier]

an idea.. this might sound crazy.. but if you are doing the whole deck, maybe you can have metal backing the cells and water cooling this metal with copper water pipe This would keep the panels more efficient, and the boat cool inside as well as providing you with hot showers, and pre-heated water for cooking.

There are many other uses for hot water.. for example banking in a tank to keep warm at night, or pre-heating a solar still to name just a few.

[seandepagnier]

I get more than the panels rated output when it reflects off the water and the panel is vertical.

Unfortunately this only happens for a very short period of time when the sun is at just the right angle.

They make panels which are clear on the back too and allow light to hit from both sides. These when mounted flat above the cockpit (to catch rain as well) can get quite a lot of light at noon)

Yes, vertical cells don't output a great deal, but they give you power when the flat cells don't (sun is low)

[Tscott8201]

Originally Posted by boat_alexandra

You should never get a hard drive or computer either because better ones will become available in the future.

You miss one little point here. A computer costs around $500 dollars today, what will it cost in 5 years to completely strip this clear coat and get these solar cells out? Not to mention the risk of a bad cell ruining the whole array. From what I understand the OP is planning to embed the cells on top of the deck in such a way as to make them more or less a permanent part of the boat. So to make your argument equivalent then the OP would need to change boats when he wished to upgrade to a new solar cell technology. So in essence you are comparing a $500 PC to what is most likely a $100k + boat.

To the OP, with the age of nano technology upon us I would strongly urge you to choose a more flexible alternative to your plan. Although I like the idea, and think it would probably be kinda cool. I really think when dealing with something as technology sensitive as solar panels and electronics all effort should be made to make these systems upgradable. If you proceed with your plan , then please post pictures as I am curious to see how it works.

Tom

[nimblemotors]

Originally Posted by boat_alexandra

an idea.. this might sound crazy.. but if you are doing the whole deck, maybe you can have metal backing the cells and water cooling this metal with copper water pipe This would keep the panels more efficient, and the boat cool inside as well as providing you with hot showers, and pre-heated water for cooking.

There are many other uses for hot water.. for example banking in a tank to keep warm at night, or pre-heating a solar still to name just a few.

That might be a very good idea!
However, salt water might cause more problems than its worth.
It is an interesting notion using hot water to store energy.
In a warm climate, maybe you want to store chilled water from the excessive energy? I am certain I will have too much energy to keep in batteries when on the hook.

I am designing my boat for solar cells. I would not epoxy them into the boat. I plan to make the solar system attached as molded panels that fit onto the topsides that are removable. Far from needing to figure how to attach yet, but it won't be permanent.

The other important issue with setting up such a system is you must deal with "shading", or uneven output of the cells from different angles. This is a challenging technical problem that must be solved if you use a lot of panels on uneven surfaces.

JackB

[Max Sail]

Perhaps you could think of it as raising up a second deck up around the panels, basically raising the devk the height of the panels plus the thickness of a flush plexi hatch cover at each panel.. so they could be accessed and swapped out. maybe use teak deck between panels. Would depend on the effect of plexiglass covering on the panels... Might filter some frequencies of light and reduce panel performance.

Seems the more economical way would just be to cover the existing deck with those flexible walkable panels and be done with it...

But it's an interesting thought experiment. If ever end up relaying teak decks, maybe I could leave out a couple panel sized rectangles to set panels down in.
Probably would still want to solve the walk ability issue. (Also wouldn't be amiable, but with enough panels you can likely sacrifice some efficiency for the aesthetics, clearly this thought experiment isn't about most bang for the buck)

[jeanathon]

I like the way this has turned into a bit of a brain storm.
Alexandra interesting idea to use the extra heat that the pv cells cannot. You should patent it. That would be a nice compact dual purpose unit for someones roof. A bit to heavy and or complicated than what I am looking for on the boat, but might put one on my roof.
Also with your vertical mount panels how often are they perpendicularish to the setting or rising sun on the hook?
Tscott I am appreciative of ever changing technology. I am still waiting for the micro infrared antennas in our wall paper that I heard about on Science Friday 6 years ago. But the fact is this is most definitely not a 100k boat, and if the new thing in pv just came out. My boat would have to wait enough years for the price to come down enough to make it feasible. Of course by then the next thing would be ready to come out. What I cannot get in efficiency I hope to make up in quantity. Now or never.
Nimble, Now your first comment make sense. Another interesting idea. Where would you store the removable panels? What about connections? Are you going to have little pig tails sticking up through the deck when you are not using the cells? I thought of using two contact points on the hatch panels so they made contact when it was closed(deployed). I guess you could do something similar.
Keep em coming..
ps. Any other products out there other than sylgard to embed with?

[Max Sail]

Why not just use these... "Textured step on surface", curvable, etc.

Aurinco solar panels

[seandepagnier]

Originally Posted by Tscott8201

You miss one little point here. A computer costs around $500 dollars today,

my netbook computer cost $120 3 years ago

what will it cost in 5 years to completely strip this clear coat and get these solar cells out? Not to mention the risk of a bad cell ruining the whole array. From what I

If you build properly (many arrays in parallel) you get good partial shade tolerance, and small loss from one bad cell.

understand the OP is planning to embed the cells on top of the deck in such a way as to make them more or less a permanent part of the boat. So to make your argument equivalent then the OP would need to change boats when he wished to upgrade to a new solar cell technology. So in essence you are comparing a $500 PC to what is most likely a $100k + boat.

Solar cells are available at under $1 per watt now if you do all the mounting, so covering the entire deck of my boat 27' boat would cost under $2000, and I could motor at 5 knots in full sun or 4 knots 24 hours a day during summer. (in flat water) My boat is electrically driven now, but only have 25% of the deck space with traditional panels under glass. I can go 2 knots without battery drain, but my electric drive is only 20% efficient (1990 brushed motors spinning small prop very fast) These panels cost total of $500 3 years ago when I got them. Waiting on technology is probably endless; build this now. we need more solar boats. Current technology panels are amazing. If you did tear the deck out, the panels could still be mounted on a roof or something. The main problems on a traditional boat would be the boat overheating, and thus making the panels less efficient and making you sweat a lot, but maybe you can design around this. It would be ok if you are not in the tropics.