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I guess it depends on how you use it. Like on cars, solar panels don't do much of anything to improve range because the power the car consumes while driving dw

by elihu 6y ago

I guess it depends on how you use it. Like on cars, solar panels don't do much of anything to improve range because the power the car consumes while driving dwarfs the power you get from solar panels. On the other hand, if you don't drive very far most of the time, then having solar panels means charging your car less often, which could be a great thing. It's like a gas tank that fills itself automatically at a rate of a gallon a week. You'd still need to buy gas if you drive much, but still who wouldn't want that? I figure that's especially true for boats, which aren't usually daily drivers. If you use your boat, say, twice a month, it could be a nice feature to have the battery partially or completely refilled when you want to use it without having to bother to plug it in.

billjings 6y ago
Well, doing some quick googling.... Rule of thumb for a boat motor is 1hp for each 40-50lbs of weight. Say conservatively that you're 160-200lbs like myself, that's 4hp minimum. Solar panels are ~15w/ft^2. 4hp = 2983w, which is ~200ft^2, or approximately a 14'x14' panel. There's some fudging around that can be done around letting it charge for part of the day, but even with those extremely generous numbers you end up with an enormous "sail" of solar cells.
- elihu 6y ago
  Another way to look at it: I don't remember the article saying anything about how big the batteries are, but let's take a guess they're about 80kwh, similar to a Tesla. Let's say the boat can easily add solar panels to collect an average of 200 watts for 10 hours a day. That's 2kwh per day, or enough to fully recharge the boat in 40 days. If you go boating once every two weeks, then that's a third of a full charge for free. Is that worth it? It depends. It seems like a nice feature to have, and it adds some additional weight and complexity to the boat, and increases the manufacturing cost somewhat. The hardest part might be explaining to customers that solar panels don't increase the range and they'll have to plug in to charge if they want to use the boat every day.
- jjav 6y ago
  > Rule of thumb for a boat motor is 1hp for each 40-50lbs of weight. For a planing hull, maybe? Displacement hulls (sailboats, trawlers, etc) don't need (and can't make use of) much hp. It doesn't take much to get to hull speed, and basically no amount of power will make it go significantly faster. For example my 8000lb sailboat has an 18hp engine (~440lb/hp) and it could easily reach hull speed with a smaller engine in most conditions.

by elihu 6y ago

billjings 6y ago

Well, doing some quick googling.... Rule of thumb for a boat motor is 1hp for each 40-50lbs of weight. Say conservatively that you're 160-200lbs like myself, that's 4hp minimum. Solar panels are ~15w/ft^2. 4hp = 2983w, which is ~200ft^2, or approximately a 14'x14' panel. There's some fudging around that can be done around letting it charge for part of the day, but even with those extremely generous numbers you end up with an enormous "sail" of solar cells.

elihu 6y ago
Another way to look at it: I don't remember the article saying anything about how big the batteries are, but let's take a guess they're about 80kwh, similar to a Tesla. Let's say the boat can easily add solar panels to collect an average of 200 watts for 10 hours a day. That's 2kwh per day, or enough to fully recharge the boat in 40 days. If you go boating once every two weeks, then that's a third of a full charge for free. Is that worth it? It depends. It seems like a nice feature to have, and it adds some additional weight and complexity to the boat, and increases the manufacturing cost somewhat. The hardest part might be explaining to customers that solar panels don't increase the range and they'll have to plug in to charge if they want to use the boat every day.
jjav 6y ago
> Rule of thumb for a boat motor is 1hp for each 40-50lbs of weight. For a planing hull, maybe? Displacement hulls (sailboats, trawlers, etc) don't need (and can't make use of) much hp. It doesn't take much to get to hull speed, and basically no amount of power will make it go significantly faster. For example my 8000lb sailboat has an 18hp engine (~440lb/hp) and it could easily reach hull speed with a smaller engine in most conditions.