Free shipping... waste $ driving AND buying other things!! L O L

Do we know if there is any built in circuitry? Cooking them up in parallel might not be the only option. Besides, hooking them up in series would prevent you from using the charge controller and other goodies that come with it!

Looking more closely at the photos, it seems the charge controller is a stand-alone item. Still, it can only handle 4 amps, so putting two sets in parallel is not an option.

You could ditch the controller and connect the individual panels in parallel. However, you would need to monitor the battery's voltage very closely. 14.2 VDC is the cutoff point for charge controllers I've seen. Much above that and you can overcharge (fry) your battery. Hint: it always happens when you're not looking.

BTW: many higher-end solar setups are wired in series, and run at 24 VDC. Less line loss (a.k.a. the toaster effect) that way.

(There's no inverter included -- I misunderstood. Small inverters are cheaply and readily available these days. Don't try to run a Mac off one, they don't like the modified sine wave and the power supply overheats.)

Harbor Tools has a 45-watt solar panel that has a charge controller. Its normally $249.00, sometimes on sale for $199.00


Has anyone had any experience with these?

Whoa, I didn't know that! Thanks for the warning.

-Blast

I should qualify the Mac thing:

As of a year ago, the word on desktop-ish Macs was: avoid modified sine wave inverters, period.

I have no solid info as to whether this applies to laptop-ish Macs. Ask the question of a suitable guru: "if I do this, will it cook my loved one / void my warranty?"

FWIW, I have never used a cheapo inverter on a desktop wintel box (yeah, chicken) but I have logged many hours on wintel laptops powered by uber-cheapo modified sine wave inverters. Not so much as a hiccup on three different machines. So it all lies in the design of the power supply.

As a person who's worked for one of the largest computer makers in the world I can safely say that no major brand computer company would question you about what you plugged a computer into if it fried...they're much more concerned with your safety. If they're not, buy from somebody else.

Most notebook computer supplies are designed to be pretty robust these days. The premise behind a notebook is that you could be anywhere and plugging it into anything. With the exception of some high end power hungry models, they're pretty forgiving in my experience.

A desktop model is another creature all together. Power supplies in desktops are pretty standard and the basic design hasn't changed much in a long time. Unfortunately this is a common area for cost cutting. That said, I'm not surprised about the warning on desktops. A computer you build yourself would be much more tolerant especially if you installed a top of the line power supply.

If your goal were to run a desktop off of solar power exclusively (don't laugh, you can already buy such things retail) you could build your own computer and then get a DC-DC conversion power supply designed for use in car based PCs. A small battery and some solar panels later, you'd be in business no inverter required. And these power supplies are usually about the size of a candy bar because there's no transformer needed...it's all solid state.

I somewhat agree with this but for different reasons. If you buy 2-panels, you will get a controller for each one. One controller to each panel tied together downrange of the controllers would float each solar panel from the other one and allow each controller to only have to deal with the output of one solar panel.


But I would make a guess that this would give you problems because the output from one panel and controller could easily effect the other controller by fooling it into thinking the battery has more of a charge then it really does.


The best way to tie two solar panels together is to run both of them into one controller that is made to handle the combined output of both of them. Solar charge controllers are not super expensive, so all you need to do is to buy a bigger solar controller.


Wind power controllers are expensive (they need a dump load and generally have to handle much more power then a solar controller) but solar ones are not too expensive.

Fair enough, BobS. I have a 10A charge controller that cost me about $30. And it does look like the panels in this setup are independent. So, you can reconfigure as you please.

But here's the rub, as I see it: this package is less and less of a deal if you have to start adding external components.

I would argue that if you buy two of these setups, you'd be better off keeping them separate, hooked to appropriate batteries.

On that theme: deep cycle batts are nice, but cheapo inverters are designed for car batteries and shut down at ?? 10.6 volts (I think) to prevent damage. So, the xbox goes down, tough luck kids. But the second batt keeps running the LED lighting and the radios, which really matter.

My 2-cents' worth.

Ah, so you were caught in the local **ll meltdown? Bad luck, dude. Hope you came out okay.

I agree with everything you've said about desktop vs. laptop power supplies. It agrees with my own experience.

No reason a desktop can't be run off pure solar. My 120 watts of generation (growing all the time) does a lot of real work around here. Any info you can provide on DC-DC units would be welcome. I hate losing 15-20% of my juice to inverters.