On Dec 22, 9:36*am, wrote:
On Dec 22, 9:10*am, N8N wrote:





OK guys...

I have a rather dark, shaded lot. *Having lighting on the walkway to
my front door, and perhaps on the steps leading up to the deck at the
back of my house, would be a very Good Thing. *I'm not real impressed
with any of the solar lights available, but I have an idea. *Could I
perhaps use a solar cell to charge a 12V UPS style battery (7-10 AH?)
then use a photocell to switch the 12V from the battery to a string of
regular low voltage lights whenever it gets dark? *Where would I go
about finding an appropriate solar cell and charging circuit to make
this work? *Are there any good LED style low voltage lights on the
market, or are they all pretty much still incandescent?

thanks

nate

In theory it should work. * The trade-off is how big of a solar panel
you need, how much it costs and weighing that against the the lower
power requirements of LEDs versus incandescent lights. *The battery
part should be the easiest, any boat type deep cycle battery should
work fine. * The solar powered LED walkway lights I've tried from HD
were marginal. * They are barely bright enough to light up the edge of
a walkway so you can see where to walk, but not bright enough for much
more than that. * There are probably other LED lights available with
higher output. * *The problem with the self-powered ones, as you
already know, is that they need to be in full sun to get enough
charge. * Driving down the street I see lots of half-ass ones that are
barely lit.

that, and the solar panels are of ****e quality and don't last. And
the overall construction of them is just garbage. Yes, we bought some
HD special solar lights when we moved in and they're all trash now.


By splitting off the solar panel to a good location, no reason your
approach would not work. *I see solar/battery powered blinking lights
along the road now in many places and that is what has been used for
decades for most waterway flashing buoys.

The only obvious question is whether for the small amount of $$ it
costs to run some sidewalk lights is worth all the trouble and cost of
implementing what you're talking about. * For example, the battery has
to be replaced at some point and I would bet that alone could equal
the cost of just using electricity.

One place you could start to look is at solar panels sold to keep
cars, rv's, boats, etc charged. * Also, I'm sure if you type in solar
panel in Ebay you will find some quick info.

Battery cost is not an issue for me; where I work we regularly deal
with this kind of stuff so I could probably even get old batteries
that don't meet their ratings anymore for free just by sorting through
the junk pile. My real problem is sorting the good stuff from the
junk when it comes to solar panels, I just don't have a whole lot of
knowledge in this respect.

Or I suppose I could just "liberate" a solar panel from one of those
roadside sign things :P (no, seriously, I wouldn't do that...)

I think I have a couple of those plug-into-your-cigarette-lighter
solar panels that used to ship with new VWs to keep the batteries
topped up, but I suspect those may not have enough onions to do the
job...

really, my purpose in this whole exercise is just to see if I can do
something cool and efficient that will actually work; I don't really
expect to save any money. Having a "free" topped up 12V battery in my
basement would be a nice bonus for when the power goes out, although
of course it's just as easy to grab a battery out of one of the cars.

nate