Solar on the Hull ?

[drew.ward]

Just curious, has anyone on here every played around with putting solar on the hull of your boat?

We've been playing with the idea of attaching thin-film flexible solar all along the sides of our hull between the water line and the deck. The flexible cells are about the same colour range as the black and blue paint schemes of many boats and our thought is that we could be creative with paint and blend the panels hiding their appearance. The idea is to take advantage of what is in essence a very large wasted space that doesn't see much use versus giving up valuable flat horizontal space above decks.

Flexible solar has a lower photovoltaic efficiency than the fixed panels do, but they are less prone to damage and can be applied in more creative ways. The hull also being vertical to at points somewhat downward facing also would be less prone to direct sunlight than standard mounting. Our idea is that the approximately 3,000 sq ft of panel space would allow us to make up for these losses and still produce a decent amount of power.

It's our thinking that the water surface will reflect enough light up onto the vessel during midday hours to provide solid electric potential, and that the vertical hull placement will actually provide an advantage during morning and evening hours where the sun is lower on the horizon. Another option we are looking at is installing a sort of upside down retractable awning that could be extended outward from near the water line, and, being made of an aluminized plastic or canvass, reflect light back up onto the panels at the ideal angle, actually giving a stronger intensity than would be possible even on a horizontal plane. This sort of feature would likely be limited to slow cruising or stationary service but considering the simplicity of the parts involved, could be a great way to produce extra electricity without giving up all the useful surfaces of your boat.

Thoughts anyone?

I'm guessing I'm not the only one who's thought of this...

[denverd0n]

Flexible panels are generally less efficient, but they're also generally far more expensive. Putting them in a much less than ideal location sounds like a really good formula for spending a lot of money to accomplish very little. Personally, I wouldn't even consider it.

[micah719]

When the technology gets to the stage where the flexible panels' properties approach useable sailcloth, there might be some potential...

The thermoelectric effect was something I found intriguing, haven't looked further into it yet.

[belizesailor]

Putting panels on your topsides is certainly physically do-albe and would generate some output, but not likely at full power because the angle to the sun will be way off in most latitudes. Research proper angle adjustment of panel relative to latitude.

[drew.ward]

All good points...

I suppose I should have prefaced this with the fact that this is for a demonstrator vessel which will be testing and refining application of various green technologies to determined what sort of things that are available today are practical and viable options for boat upgrades within the marine world. As such, some of the initial installation costs will be higher than anyone in their right minds would want to pay and the return on our investment from a pure numbers standpoint may not be that great. But, our intended return is more in moving certain currently high cost (read out of reach) technologies toward commercialization and honing them to the point that they are both affordable and practical and at a price point where we can all justify buying them.

As to solar, the thoughts for us are what good is solar if you can't afford it or if you can't put enough of it on your boat in places that won't result in damage to the solar arrays or detract from the enjoyment and usefulness of your vessel to make a difference.

The way we see it, all the parts of the puzzle and all of the needed technologies are out there, but instead of taking the general approach of trying to reshape boats and boating around using certain technologies and products, we want to find ways to shape those technologies around the way we live and work on our boats and on the water.

To me these supposedly "successful" green yachts that take the form of a trimaran so wide it could never enter most marinas that has solar panels on every flat surface leaving the only "yachting" to be done taking place below decks and resulting in a boat that's capable of cruising the world at 4 knots but doing little more than moving itself in the water are jokes and wastes of money. Figuring out how to meet the energy needs of the thousands and thousands of existing boats on the water today without changing the way we sail...that makes sense (and it's cheaper!).

Regarding the hull-solar applications, as I said in the original post, we do realize that at current technical levels that the production on hull-surfaces may not be the best. But, we do as mentioned have some ideas (such as movable reflectors) that could augment the efficiency and production of them. Also, while thin film is less productive, the vastly larger surface area afforded by using the hull is something that it seems a shame to waste. Ideally, we think that if we can show that the application works, that improvements in manufacturing and efficiency could be justified by the added market potential across the marine industry.

I suppose it's possible to actually adapt rigid solar to a vessel hull and this is something we've considered. The trick would be first not making the boat look like crap and second protecting the panels from damage. It may be that in the end, an adaptation of more mainstream rigid panels is justified by the lower cost and higher performance over flexible thin film cells.

One option we are considering is moving away from photovoltaics in general and instead leveraging the heatsink effect of the hull to produce power in ways similar to what is done with solar hot water arrays. These are much simpler and sturdier and low tech materials and leave only the challenge of determining how best to convert captured heat into stored energy.

The sailcloth idea is a good one too I think. Even more so sometime in the next decade as photovoltaic paints move from the lab and into production. For a sailboat to be able to leverage the great surface areas of their sails not only for propulsion but to generate onboard power would be a major step forward.

We actually have something like this going into our project via our wind propulsion system. It's a yacht-scale version of the kite-propulsion system used successfully by SkySails on several large commercial vessels and tankers over the past few years. This system will provide all of our propulsion power once out of port but will also be a major source of electricity through regenerative propeller functions. We're building into the system a third feature though that actually lets the kite itself via the slight changes in line tension while maintaining its flight patterns to generate electricity. This means it will eventually be able to deliver a constant 50kw of steady power not only while in motion but even when anchored or in port regardless of surface winds. The more things like this that come to fruition, the better our viable lives aboard are destined to get!

[Infinitee]

Would love to hear how the tests come out, please share the data if you can.

Here is another idea instead of flexible cells, a paint-able battery

Rechargeable battery can be painted onto almost any surface | Springwise

Just being developed but what potential!

[David M]

I bet one day the technology is available where solar panels can be built into the deck and hull when the boat is glassed in the mold. That would be pretty neat to have over a thousand watts available that is not in the way.

[maxingout]

Draping the hulls with solar panels might work in port in the right location around the world, but offshore the panels would not survive with the present state of technology. I don't think that vertically oriented panels on the sides of the hull would be that efficient.

Designing a yacht around solar panels might work for some people, but it would not work for me. There are simply so many other ways to generate electrical power that are easy and convenient.

I hope I never get to the point that I need kilowatts of power to go cruising. I think it would drive me crazy to run a floating power generating facility. A couple of solar panels, a wind generator, and an alternator on the engine are affordable and relatively simple to maintain.

If cruising gets too complex, I don't think I would want to do it.

To me the spirit of cruising is not a power hungry replication of short-side power consumption. I guess that I am not a kilowatt cruiser.