how would you generate this little power ?

[simonfraser]

i run an anchor light on my boat, on a swinging mooring, 0.1 A per hour.
my current three solar panels, 12W each !! generate 0.1A per hour in december, mid day!
so, not enought for 24/7, i need solar power of 0.35A per day light hour, or a smaller amount via a wind generator.
rutland used to do a vertical column shaped job, can't seem to find it.
suggestions ?

 

[jeremyshaw]

That does seem remarkably little output from the panels. Are you sure you are not losing power through corroded/poor connections as happened to me? Check the output as upstream as possible. Also if you have a regulator fitted that will knock some power out and you probably don't need it for that amount of wattage, unless you have a very small battery.

 

[pvb]

Forgen...

[ QUOTE ]
rutland used to do a vertical column shaped job, can't seem to find it. suggestions ?

[/ QUOTE ]You're probably thinking of the Forgen.

 

[Talbot]

You are thinking of the forgen - about as useful as the solar panel output you are getting now. The Rutland 513 might be a better choice for (what I suspect ) a small vessel

 

[lw395]

Aside from your abuse of units, i.e. should be Amps as a unit of current, and AmpHrs as a unit of charge, The 0.1A you give for the anchor light seems very low, that's a 1W bulb?
Is that what you meant? Assuming 12V, you could run 3 white led's in series at about 30mA or maybe 2 pairs of 3 to give better 360degree coverage. Use resistors to set the current.
The output of the panels does sound disppointing, are you sure they are wired for 12V, do you have too much voltage drop from the panel to the battery? Sometimes there is a built-in diode, so if you add another diode in series the panel won't be so effective.

 

[alldownwind]

Your 12W panels would each generate a current of about 1.0A in perfect conditions - totally clear unbroken sunlight shining vertically down onto them, and a battery sufficiently discharged to accept a charge current of 1.0A. You don't say where you are, or how you have them mounted - if you are in UK, and have them mounted flat on deck with stuff like a mast occasionally in the way, or the battery is pretty well fully charged, then I'm not surprised at the feeble output.
If they are mounted so that conditions are perfect, then there is something wrong with the wiring.

 

[sailorman]

or why he needs a light on his boat on a mooring in December

 

[alan]

If your panels are rated at 12W peak then they will give 12W at the rated peak voltage which is probably 17v, 19v or 20v .... depends on panels. Assuming 17v this will give a peak current of something like 0.6A. I doubt your panels ever give this max current, so for rough calcs you can consider 2/3 of that (from my experience and measurements).. so maximum current of 0.4A for three or four hours in England in winter if you are lucky; thus say 1.5Ah per day per panel ... a total of 4.5Ah per day.
Your lamp consumes 2.4Ah per day if it is on 24/7; so in theory you should be able to maintain this load. It is possible to fit a light sensitive switch so that your lamp is only on for (maybe) 12 hours a day and thus consuming 1.2Ah per day and with this you will be in a better position to hold your own.............. but depends a lot on weather.
I suspect that your main problem is that on a swinging mooring you are not getting anything like the amps from the panels that you can get in theoretical calculations. To get these maximums you need panels that are angled toward the sun, are motorised to track the sun and also a "fixed" base ... not a swinging boat ... and also a clear atmosphere.
So, your idea of a wind gen is a good one in those circumstances.

Alan.

 

[EDM]

Why not include a Photo Sensative switch in the circuit - so only in times of darkness the anchor light goes on ? Have a look at this West Marine Photo Switch

Giving your rather weakly charging solar panels more time ?

 

[simonfraser]

thanks for the info, the panels are mounted flat, so obvioulsy not orientated well. boat on a swining mooring, i have had two recent scrapes down the sides, hence the led anchor light. yesterday, when the sun came out a bit the meter showed 200mA. during the summer i get 1+ A per hour. i'll keep the connection problem in mind.

forgen, thanks, that will make me find it

i'll check out the photo switch too, just as long as it draws less than the led anchor light, triton one, it gives good visibility.

 

[Noddy]

[ QUOTE ]
Why not include a Photo Sensative switch in the circuit - so only in times of darkness the anchor light goes on ?

[/ QUOTE ]

Sounds like those solar lights you get for the garden.

 

[DRANNIE]

I suspect your answer may lie here, there are full instructions on how to construct your own low energy generation. I suspect you would need to visit every couple of weeks for servicing and and fuel but should be low cost. The motors are about £3 to replace which is favourable when you consider the cost of a rutland generator. Based on the power output I would probably recommend 2 in paralell for redundency purposes.

clicky