R/C solar-powered sail boat project

[John_Lee]

I've just completed building a fairly long sail boat, a
radio-controlled boat, which is to be powered by both batteries and
solar panels, along with the help of the wind. I'd like to use
separate flexible solar panels, they are extremely light in weight, to
power one small DC fan and one bigger DC fan. Here are the
specifications of those fans: small fan (Rated Voltage: 12VDC, Rated
Power Current: 0.15 Amp, Rate Power Consumption: 1.8 W); big fan
(Rated Voltage: 12VDC, Rated Power Current: 1.0 Amp, Rate Power
Consumption: 12.5 W). These fans will be placed in a way that they
blow air at the sails, thus propelling the boat. I would like to sail
this boat for 5 hours non-stop.

My question: based on the specifications of the fans, what are the
sizes for the solar panels (in terms of Rate Power Consumption) for
the small fan and the big fan? Thank you.

John.

 

[Charles Jean]

On 8 Aug 2004 01:40:07 -0700, wanghes@hotmail.com (John_Lee) wrote:

I've just completed building a fairly long sail boat, a
radio-controlled boat, which is to be powered by both batteries and
solar panels, along with the help of the wind. I'd like to use
separate flexible solar panels, they are extremely light in weight, to
power one small DC fan and one bigger DC fan. Here are the
specifications of those fans: small fan (Rated Voltage: 12VDC, Rated
Power Current: 0.15 Amp, Rate Power Consumption: 1.8 W); big fan
(Rated Voltage: 12VDC, Rated Power Current: 1.0 Amp, Rate Power
Consumption: 12.5 W). These fans will be placed in a way that they
blow air at the sails, thus propelling the boat. I would like to sail
this boat for 5 hours non-stop.

My question: based on the specifications of the fans, what are the
sizes for the solar panels (in terms of Rate Power Consumption) for
the small fan and the big fan? Thank you.

John.
___

If you are trying to do what I think you are trying to do, you'd
better reread Newton's third law. Will the fans be attached to the
boat?
___



GRAVITY:

It's not just a good idea-IT'S THE LAW!

 

[mdscientist61]

(John_Lee) wrote:

I've just completed building a fairly long sail boat, a
These fans will be placed in a way that they
blow air at the sails, thus propelling the boat.

You would be better off to mount a rather small fan on the end of a
shaft, then drill a suitably sized hold at the stern of your boat,
take proper steps to prevent water from leaking around the shaft, and
connect the shaft to the motor in the belly of the boat. Make sure the
fan remains under the surface of the water and rotates such that it is
pushing the water backwards. This arrangement would be more compatible
with Newton's laws of motion, since the fan would be pushing against
the water rather then blowing air into the sails.

Good luck!