There’s an old thread over on the solar board about these (http://thesurvivalpodcast.com/forum/index.php?topic=18423.msg220922#msg220922
), but after dealing with them for a couple of years I figured I’d write a full review. Maybe some of this is redundant, but hopefully there’s enough new stuff to make it worth reading.
Pro: All-in-one gets-you-off-the-dime small turnkey system. Good for small amounts of emergency electricity. Three independent panels give you some room for error.
Con: Not the best build quality. Don’t expect this to run your whole house.
I bought one of these systems almost two years ago and, living within its limitations, it works. But its limitations are pretty severe. Here’s a link to the site, so that you can see what I’m talking about: http://www.harborfreight.com/interests/solar-power/45-watt-solar-panel-kit-90599.html
What you get in the kit is three 15 watt panels, a rudimentary charge controller, battery clips, and a couple of pre-wired compact fluorescent lights. The charge controller also serves as a junction box, with a auto cigarette lighter plug-in and several output voltage options. The CFLs plug in with 1/4” phono-plug-looking things. It’s all pretty easy and color coded.
The panels are... OK. They’re cheap amorphous silicon cells mounted in cheap aluminum frames. The connectors on the back don’t look especially weather tight. It’s not something you’d want to permanently mount on your roof, it’s more of a “put it in the yard on a nice day when you need it” proposition. As a backup to get you a little electricity for a couple of weeks after a hurricane, it’d be fine but you might consider bringing things in at night. After nearly two years of rattling around the shed and getting intermittent use and a few surprise rainstorms, mine are pretty much like new. And they do put out something close to the rated power. On a recent sunny-with-a-few-clouds weekend, I measured their output at 35 watts, and have little doubt that on an wow-it’s-bright day they’d put out something close enough to 45 watts. No worries there.
One thing that I do like is having three panels, there is some redundancy built in. If one panel breaks, it can be taken offline and you rock on at 30 watts. Everybody with kids knows what I’m talking about.
How big a battery? 35 watts / 12 volts = about 3 amps. 3 amps x 8 hours (optimistic, I know) = 24 amp-hours. The usual recommendation is two+ days of capacity, so something in the 50 amp-hour range would be about right.
About the rest of it, the controller box is pretty rudimentary. I’m not sure that it would prevent over-charging or over-discharging the battery, and the manual isn’t particularly helpful on that point. It might be worth picking up a $25 controller to keep from over-charging.
Which brings us to the next question: how’s it stack up in price/performance to better grade systems? Well, here’s a 45 watt panel for $150 (http://www.solar-electric.com/spm040.html
), and a probably better controller for $25 (http://www.solar-electric.com/sg-4.html
), or a lot better controller for $48 (http://www.solar-electric.com/ss-6l.html
). Right there, we’re up around the list price of this Harbor Freight thing’s $190 tag, but you still have to buy the lamps, cigarette lighter connect, and battery clamps, and then wire things up yourself. Easy for many of us, but my brother wouldn’t know where to begin. It would be a much better system though, and it probably wouldn’t be hard to find similar stuff at a better price. (Remember, it’s all 12 volt, and 12v gear doesn’t hit the sale table too often.) On the other hand, Harbor Freight is always running sales and coupon deals, so you can probably come in well under $190. (I think mine was $160 with a coupon.)
Which takes us to the wrap-up: what good is this system? It’s OK for a back-up to give a little electricity when there’s none to be had. It’ll charge a cell phone and run a couple of lights, run a CB or ham radio, maybe turn a shallow well pump or a fan. It comes in one box as a kit, and most people can put it together. It’s modular and can be upgraded in bits. (That’s what I’ve done, and now I’ve got an entirely separate “good” 140 watt system, with the Harbor Fright sitting ready as a spare.) But best of all, this system got me off the dime and into small solar all at once, and got me started building a real system. Thinking of it as both a hands-on learning tool and a power source may make it worth the money. Call it 3 out of 5 stars, give or take a star depending on your situation.