The Ownage

I realized it was nearly a year ago when I first mentioned the Solar Project that I wanted to do. What better time to work on it than now, when I am in between jobs? Of course there is the no-income issue, but I’m doing okay for now, and I have some ideas to keep the cost low.

First, I had to decide how much solar power I wanted. This is dictated by 2 things. Cost of solar panels, and a place to put them. I definitely have the space, but cannot afford a huge array that can power the whole house. Also a solar setup which can power your entire house has lots of extra costs in the electrical hookups to your utility breaker box, plus code inspections, etc.

So, I’m thinking of providing solar power to something that uses a lot of juice, but only periodically, which is means the battery bank has time to recharge in between usage. A garage door opener fits this bill perfectly. It uses a lot of power to run a 1/2hp motor for 30seconds for open and close, and is only activated maybe 3-4 times in a 24 hour period. It also plugs into a single outlet with a standard plug, making it easy to isolate the circuit.

What else could do with solar power? Besides saving some $ for all the juice that the garage door opener usually uses, I also have a small power reserve for power outages. If there is an outage I can run an extension cord into the house and power fans, lights, and even a microwave oven (assuming I have a suitable power inverter, which I do). I won’t have enough power to be totally “off the grid”, but I will have enough to run bare necessities for as long as needed.

I have already purchased most of the items I need:

• An 80 watt mono-crystaline solar panel (can get from ebay for literally under $200). This sucker puts out 5amps of 17.3v DC power.
• A charge controller – This is an (thankfully) cheap electronic device that goes between the solar panel(s) and your battery bank. It keeps the panels from over-charging the battery by regulating the power flow when the battery is fully charged.
• A “pure sine” power inveter. A power inverter converts DC power (usually 12v) to AC (usually 110v). I got a 1500 watt pure sine power inverter. Pure sine inverters are needed to run electronics as well as large motors like a garage door opener. Pure sine inverters cost 2x more than the typical cheap inverters, because the cheap inverters use a simple circuit that creates AC current that looks like a square wave, which is too “rough” of a cycle for most things to work properly. A pure sine inverter puts out clean power that is just like the AC power from your utility line. The inverter that I got can output either 110v or 220v, and has a max output of 3000watts, which is more than enough to handle the startup draw of a garage door opener or even an 800w microwave.

There are some other things I will need to put this all together. Like a couple of 12v batteries, various cables and connectors. I am first going to build a self-contained mobile prototype, and then once I confirm that it reliably produces enough power for the garage door opener, I will move the solar panel to the garage roof and hardwire the battery bank, inverter, and charge controller in my storage room, then split the 110v outlet that my garage door opener plugs into, and make the other outlet of the pair a solar-powered one.

I’ll post pics and a video in the next followup.

This entry was posted on Friday, March 5th, 2010 at 11:53 am and is filed under House, SCIENCE, Technology. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.