How to get started on a solar power project

Whether as a weekend hobby or for powering a data center, dropping solar panel prices will ultimately make solar a viable energy source.

solar lead image

Solar panels at Marine Corps Air Ground Combat Center Twentynine Palms, Calif.

Credit: U.S. Marine Corps photo by Pfc. Jeremiah Handeland

If you're looking to power projects, whether it be a fully-fledged data center or just a hobby shack in the yard, you've likely looked at expensive solar options.

Well, a recently released report confirms what we might have suspected - solar prices are indeed dropping, and dropping hard.

The Energy Department's National Renewable Energy Laboratory and Lawrence Berkeley National Laboratory reckons distributed solar photovoltaic, or PV system, prices were down 12% to 19% in 2013, and will continue to drop by a projected further 3% to 12% by the end of 2014.

The report says prices will continue to fall after that.

The reason is cheap Chinese imports, among other things.

Examples

The report discusses distributed systems, which are usually connected to the grid. But the price drops are prevalent across all solar systems, including the kind used in a do-it-yourself or hobbyist sense.

A perusal on eBay produces some decent examples. Renorgy has a 100-Watt monocrystalline panel with free shipping at $128. The same panel is available on Amazon with cables, a charge controller, and brackets for $184, also with free shipping.

Monocrystaline panels are the most efficient, and the most expensive. Polycrystaline,is a cheaper form of panel. It doesn’t work as well in cloud cover.

The charge controller is used to regulate power to the battery. These prices don’t include batteries.

Getting started

Assuming you’re not quite ready to build your solar-powered data center, or multiple-megawatt solar power plant, in the middle of a desert somewhere, but do admire them, you can get into something similar as a weekend project for a few hundred bucks.

I built a 55-Watt portable kit with flexible solar panel and battery pack for wild, in-the-boondocks camping. The solar panel lets me stay out for more than a day—I don’t have to run a vehicle alternator to charge batteries for a laptop and or cellphone.

Other applications include the aforementioned back-yard shack, a twenty-first century connected hunting blind or disaster prepper kit. After all, you don’t want the world to end with you unprepared and without power.

Sources

I found that the best source of information when building my camp kit was Flagstaff, Arizona-based Northern Arizona Wind & Sun’s website.

It has a fabulous product resource with swaths of information on how to choose gear, like inverters that convert the 12-volt solar power to 110-volt household supply. Other must-read subjects include the Battery FAQ.

It will also sell you the panels and other stuff you need, and is particularly strong on appropriate batteries—you shouldn't just use auto batteries because they don’t deep cycle well.

Projects

I found my solar scheme an immensely satisfying project. With winter just around the corner for much of the country, and many looking for cabin-fever reducing workshop assignments, I think a small solar project could be good for this winter—particularly with solar’s previously unattainable prices dropping like they are.

Who knows, if you really get into it, you can ultimately expand the system and end up selling power back to the grid—and make your development cost back. Tax breaks and grants are also available.

You’ll also be developing expanded knowledge and learning skills related to power systems, wiring, batteries, and so on—which will be good for network-related careers.

Things to know

Panel output is measured in watts, battery storage is in amp-hours, and charge controllers measure in amps.

Divide watts by voltage to get the amps output. Theoretically, the 100-Watt 12-Volt panel puts out 8.33 amps. So your charge controller needs to be at least 8.33 amps. The panel actually puts out more than that, so add a margin of safety. I use a 10-amp charge controller on my 55-Watt panel.

People roughly match battery amp hours with solar panel watts. There’s no calculation or chemical reason; it’s just a good way to figure if your battery capacity is about right for the panel, they’ll keep up with each other. For example, a 55-Ah battery is good for a 55-W panel.

And that should get you started on your road to solar data-center management.

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