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Solar Boat Solar Panel Boosting Answered

Hi. I am a student who yearly participates in a solar boat regatta, and is wondering how he can boost his panel's rate of energy... collection. I have thought of trying reflectors, and am wondering if this would work. anyone know, or have a better idea?


Well then drag sounds the most important point to tackle - however weight will impart drag by needing more hull displacement aswell, if you were able to get lighter weight batteries like a prius one or something it'd be amazing but probably not cheap or possible to get for free, a marine deep cycle battery would be more amp hours but may be heavier, for the drag big cranking amperage is good, for the endurance a good technique might be to work out exactly how much power you're using at max speed and at cruise speed, you could possibly be able to run an hour on a full charge and top up from the solar panel, with say 10% left over as a safety net, that way you're likely to be able to go flat out as long as possible. For one idea would be to construct a rudimentary jet impeller, it mightn't be feasible in efficiency terms but if it was you could get a high top speed without compromising as much acceleration, plus it could be built in to the middle of the hull/pontoon (with the pontoon two very small ones as might be and idea.) The only thing about running a jet impeller is that it does take a lot of energy so it might be hard to source the bits. The only other thing that I can think of is using a monstrous screw propeller that basically encompasses part of the hull and two pontoons either side for balance - It'd be a bigger build but would make a good cruiser... Of course if it has to be electric you could go mad and go for the insane scientist prize with Ion propulsion or to make a confusing boiler machine, I'd say inductive heating might be capable of being efficient but you'd need damn good solar panels.

Hmm, would it be unreasonable to have batteries? That way you could be charged up for the drag and slalom... Or go with the maximum possible amount of array power and really minimize weight, then focus on drag, get as much of the boat as possible out of the water, maybe something either inflatable or foam based materials. Also get the most power possible from the motor and panel combo, then go for as efficient a prop as possible, maybe consider having two gears, allowing for a high cruise speed once you've built up a head of steam, shame you can use heat powered stuff, a monster parabolic mirror and boiler would be amazing, even just a huge putt putt boat would be cool - actually it wouldn't matter if you won, that would be amazing...

reflectors could provide a bit more power but you can damage the panels and it might be more weight than it's worth. How big are these boats? Full size or little - if you can make it light enough consider four or three streamlined pads of foam or polystyrene with a small frame between and the only other bit in water being the prop - it'd greatly reduce the drag created in moving along but you'd need to have enough flotation because if the frame's in the water it'll drag more and might sink too!

KJ is right about the reflectors, with the increase of heat on the panel you'll actually end up generating less power then you would generate with out the reflector.. (( And yes they don't last as long if they get hot )) How far do you have to go ??

In that case, you'd be better off increasing the area of the cells, whilst at the same time cutting their mass. If you're part of a team, I would recommend you split the team into two parts - one to work on the cells, motor and drive, the other to work on as light and streamlined a hull as possible. I would,personally, be tempted to purchase a single large block of expanded polystyrene and carve the hull from that, then paint it to make it as smooth as possible. (We are talking full-sized people-carrying boats here, aren't we?)

Does it have to be solar electric?

Have you thought of trying a solar stirling motor? A parabolic dish or a fresnel lens concentrates the heat of the sun on the hot end of a stirling heat engine, which turns the heat directly into mechanical work.