Saturday, July 12, 2008

Strawberry Jam

Posted by Picasa

I saw Nicole made some strawberry jam and I was a little bit jealous. So here's my collection of strawberry jam I made this afternoon. It's pretty amazing that you put in 2 cups of fruit and 4 cups of sugar to make the stuff. It's got to be good!

Monday, July 07, 2008

My Solar Powered Yard Lighting

It's been a long time since I've posted, but I've got a little project I'm excited about.

About a year ago we went to see our good friends the Poppes who are now living in New Jersey. Besides being a great doctor and helping me out a lot in Guam, Matt has talked me through a lot of projects and love to tinker with new ideas. While we were in New Jersey he showed me how he was using a solar panel and a deep cycle battery to provide all the power he needed in his tool shed for lights and his electric tools. I was pretty impressed.

After we got home, I started looking into different solar projects we could do around the house. I'm not the hard-core environmentalist type, but I have to admit I covet using less gasoline and someday hope to put a solar array up on our house. The big solar project is $20,000 before tax incentives and not very feasible on our tile roof (maybe after we add on a new garage we could put it out there). Anyhow, the big project was out of reach, so I came up with a smaller project to test out the idea of using solar energy: power our backyard lights with a solar panel.

I know you can buy solar powered lights now, but all of the ones our neighbors have are pathetic little underpowered things that end up looking like runway markers on the sides of the driveway and don't illuminate anything. There are more expensive lights that will put out more light, but they each need a separate solar panel, so the backyard would end up looking like a solar farm and at $50-120 each it quickly adds up to more than I thought yard lighting was worth. And by the way--I think even what I spent is a lot more than yard lighting is probably worth, but this is about the experience too.

I did some rough planning and ended up calling Matt for a little help. He reviewed Ohms Law with me (Volts x Amps = Watts) as well as the idea of watt hours. I figured I would be running about 200 watts of lighting when all is said and done. I looked into using LED lights instead of standard bulbs to try to decrease this output. You could power about 10 LEDs of equal brightness with the same amount as 1 standard light. Only hangup is that the LEDs cost at least $30 each (closer to $40 with shipping). Maybe I'll covert someday, but I went with the $7 standard lamps from Lowes. If you figure that I need the 15 10 watt lights to be on 3 hours each day, that ends up being about 450 watt hours of electricity a day. I had to get a solar array that would be able to put that much power back in the battery each day. I figured at least 10% would get lost as inefficiency (probably it's a little worse??).

I looked around the internet and found a couple of sites to help you figure out your array size. One of the factors that goes into it is how much sun your panel will see every day. This takes into account average weather and day length. Here's an insolation map of north america:

Tucson has an average insolation number of 6.57. That's among the most sunny spots in anywhere in North America, which means whatever panel I got will make more electricity per day than the same panel that you buy. Sorry. But it also means that I will have to suffer through the summer heat here.

So if I get an 80 watt panel and it works for 6.5 hours a day, that will give me about 500 watt hours of power a day. Now to find a panel.

There are several stores in town here that offered me a 80W panel for about $500. They would come with service and a warranty. I looked on Craigslist for a month for a used panel but never found one at a decent price or the right size. But I found a used panel on eBay for $350 that came with a 10 amp charge controller which I was going to need anyway, so I bought it.

The fun was just beginning--now I had to put it in and hook it up. Maybe that's a story for another day. . . .