Inexpensive DIY Solar Power - The $600 Kit
by Michael Graham Richard, Gatineau, Canada on 10.15.05
We all know that outfitting a house with solar panels is not cheap right now. Harnessing enough sun to be able to live completely off-grid costs many thousands of dollars, up to many tens of thousands depending on how much electricity is needed. But do we really need to go from 0% to 100% clean energy in one go? That's not usually the way things are done; we usually do incremental changes. The idealist will say that it's not fast enough (and might be right), but the realist will say that the mainstream has more chances of going for it if it's not too radical and expensive, and that the power of numbers is hard to deny. So the question is: Do we really need to go 100% solar at once? What is the least you could pay and still end up with enough solar juice to run some things around the house? The Off-Grid weblog answers that question.
For $600, you could get yourself enough solar power each week (about 1KWh) to:
run a 20-inch tv for 20 hours, a portable stereo for 100 hours, a laptop computer for 40 hours, or a 12-watt compact-fluorescent light bulb for 80 hours.The 800-watt inverter (with a 2,000-watt surge capacity) will run a small vacuum cleaner, a drill or a small drill press, a sander, a jigsaw or small band saw, but not a large circular saw. It will handle many toasters and coffee makers, but not all. A blender would be child’s play for this inverter, a microwave an impossibility. A hair dryer on low, yes; on high, forget it.
Here's what the "$600 kit" consists of:
One Uni-Solar 32-watt amorphous-silicon PV module, 12 volts: $180.00One Morningstar 6-amp charge controller, 12 volts: $40.00
Two Deka 92 amp-hour sealed batteries, 12 volts: ($130.00 each) $260.00
One Aims 800-watt modified sine wave inverter, 12 volts: $65.00
TOTAL: $545.00
This leaves you with $55 for wire, battery cables, mounting hardware, fuses between components, and the miscellaneous odds and ends that are always needed for any project of moderate complexity.
Most of these can probably be found online at some of the alternative energy stores we've covered in the past.
But the beauty is that once you've go the "starter" solar system, it is relatively easy to expand it as your needs or wallet grow.
With the exception of the inverter, this system can be easily expanded. Any number of similar modules can be wired together in parallel, so long as the modules are of the same wattage. The 6-amp charge controller can manage up to three 32-watt modules, and extra charge controllers can be wired into the system, in parallel, as your lust for power begins to swell.Batteries, of course, are always happy to see their numbers multiply.
But alas, the inverter is what it is. It cannot be connected to another inverter to provide more power (though more expensive models can be), nor can it be configured to operate at a higher input voltage, should you ever get ambitious and change the system voltage to 24 or 48 volts. On the other hand, at $65, does it really matter? A slightly-used 800-watt AC power source that can draw power right off the battery is a handy accessory any vehicle would be proud to have tucked away next to the spare tire.
So, while you’re saving up to buy the deluxe 4000-watt pure sine-wave inverter with battery charging capabilities, enjoy the little $600 starter system that got your foot in the solar-energy door, and try to imagine where it all might lead.
This project is Do-It-Yourself only if you know what you are doing, and as usual when electricity is involved, a qualified electrician should approve your setup before you power it on.
(Before anyone asks: No, the pictures are not the exact pieces of hardware recommended in the Off-Grid weblog's list.)
I've got two solar lights for riding my bike at night attached to my backpack. The radio beside my bed is a solar/dynamo flashlight/radio that I've had modified so that it can also charge AA batteries. I rigged up a couple of amorphous silicon solar panels to a battery and a DC light in a failed experiment to provide a solar powered reading light (I'd have to figure out some way to hang the solar panels outside and above my third story, rented window - something my landlords would not approve). I have a mock up of a solar rechargeable single LED light and have been collecting battery operated "reading lights" to see if I can come up with a solar rechargeable reading light. I've been trying for the last six month to contact an MIT grad student who's been building electronic LED jewelery with young girls at Boston's Museum of Science to talk about the possibility of expanding the concept to include solar recharging of the batteries. I have an outline for a half hour do it yourself TV series on the variety of ways a single south-facing window can be maximied for energy efficiency and solar power.
The last mass market solar device was the garden walk light. That was introduced by Chronar Corporation about 20 years ago. Now you can buy a set of eight from Target for $35 (on sale). What is the next mass market solar device? A one window solar electric system? A solar rechargeable reading light inexpensive enough to be available to every child on Earth? A solar/dynamo flashlight/radio battery charger which is the flashlight, radio, and extra set of batteries we are all advised to have on hand in case of emergency plus a day or night source of low voltage DC power?
There are many ways to approach a full solar economy. These are some of the steps on the road. We better start walking soon as this winter's gonna be a bitch.
My question is a practical one. What company can put all this gear into a single crate, sell mail-order as a system, ready to install out of the box, so enterprizing folks can go sell them door to door in suburbia? Real Goods, hello?
The phase-in strategy could be a good idea if it makes economic sense for individuals. Couldn't this idea save more money by "net metering"-that is dumping electricity into the grid-and saving money by scrapping the battery and inverter?
Jimcoli
I hate to reiterate Jimcoli's question, but I need to know the steps for taking this mini solar kit into a net metering situation. If I could bring that to my neighborhood organization we could really make a difference. And each year adding another, and so on. Heck, with a mini turbine in addition what's to keep suburbia from becoming passive power farms? Surely some sprawl-developer somewhere can see the potential profit in that?
What would it take to incorporate this kit into a home that's already on the grid? I imagine this project would be a lot more appealing to the majority of homeowners if it could seamlessly integrate into your already wired electrical system.
If only they could provide more power. I would spend $1500+/- to have my computers run on solar energy all the time. Maybe in a year or two we will be there.
BTW, here is a link to a company that produces high quality LED solar flash lights, maybe gmoke (first poster) wants to take a look.
http://www.skylight-swiss.com/en/index.html
I repeat jimcoli and Rex Pechler's question. The article makes sense for a web site named "off-grid.net", but I don't need to disconnect from the power grid, just offset my electricity use. How cheaply can I do this? Can I just plug the inverter's output into a 110V socket? I think you don't even need to tell the power company you're doing this unless you're going to generate enough electricity to spin the meter backwards, though it might help to get a rebate.
skierpage, this is to offset your grid electricity use. the inverter (like those car inverters you can find at almost any store) has regular outlet plugs that you can plug your appliances into.
in TOronto ont where can i purchase the solar panel ./?
Jimcoli, If you want to connect the solar panel to the grid you can get rid of the batteries, but not the inverter. You have to get a more expensive grid intertie inverter. There are many sites that sell complete kits for net-metering installation, including this one:
http://www.partsonsale.com/products2.html#homekits
Sierra Solar (http://www.sierrasolar.com/) has packaged systems for mail order:
http://www.sierrasolar.com/prod_store/PS_outback.html
I am interested in using solar power but would want to know how much it would to have a 2.5kVA power system.
There is a site that sells less expensive starter kits, they would work well for taking a room off grid, or offsetting your electrical consumption-
http://store.sundancesolar.com/plsoensy.html
Anyone that is interested in renewable energy to power their home should check out www.homepower.com. They run a magazine (paper & electronic) and offer primer articles on various RE systems (solar electric, solar thermal, hydro). You can get a free copy of their mag on the site, and subscribe for a year for $15 (6 issues, electronic version).
These guys have been around for over a decade and know what they are talking about. In the past they have even discussed "guerilla solar", which is connecting your own small-scale RE system to the grid. And yes, you need a special inverter to do it, the one mentioned here won't work.