solar walkway/step lighting?

[N8N]

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

[trader4]

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.

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.

[N8N]

that, and the solar panels are of s**te 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.

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

[Art Todesco]

Depending on how handy you are, you might consider turning on one or 2 lights continuously when dark, but, then when a motion detector sees people movement, turn on the rest of the string. This should improve battery time and cut down on the size of the solar charge panel.

[JoeSpareBedroom]

The goal is obviously safety. Seems to me that the shortest path to that goal would be to install whatever lights work best in terms of illumination and durability, even if they're AC powered, **BUT** install a motion sensor (or timer) to control them. There's got to be a way to buy just sensors similar to the ones which come attached to floodlights.

Ba da bing. Mission accomplished.

[jamesgangnc]

I'd say the primary advantage to the solar powered low voltage lighting is that you do not have to run wires. Once you start running wires then you might as well use a transformer too. You won't be saving moeny if you factor in battery and solar power life cycle costs. And the impact on the environment of those items verses the power company is not so cut and dried, the battery has a pre production and disposal impact. So do the solar panels.

[Nate Nagel]

Oh sure, I *could* do it the easy way, but where's the fun in that? :)

nate

[hrhofmann]

de quoted text -

If you do go to a powered system, make sure the timer switch is on the input to the 12V transformer, otherwise you are wasting power in the transformer all the time. Only a few watts, but they add up over time.