CURRENT ISSUE
Contests
Feature Article
|
|
Issue #210 January 2008
INTELLIGENT ENERGY SOLUTIONS
Solar-Powering the Circuit Cellar
Part 2: From the Ground Up
by Steve Ciarcia
Start | Problem Solved | Pole Mounts | Under Construction | Success at Last | Sources & PDF
SUCCESS AT LAST
In my case, it isn’t just a cylinder moving against the dirt. We need to think of my pole mount as a combination of the ledge-locked footing, concrete in the sonotubes, and all the dirt sitting on top of the footing. The easiest way to visualize it is to think of a large rectangular volume with the dimensions 5¢ × 17¢ × 6¢—18.89 yards of dirt and concrete. Dirt is about 3,000 lb/yard and 6 yards of this volume is 4,000 lb/yd of concrete. Discounting the fact that the footing can’t move on the ledge without breaking it, the weight of my footing is 62,670 lb. OK, it’s for two poles, but who’s counting? I think overkill is a reasonable description.
Well, this looks like a good place to stop for now. Next month, I’ll describe how Sunlight Solar Energy got to put the racks and panels on the poles and wire this entire mess into the three inverters. That also looks like a good place to talk about more of the electronics and operational issues of large grid-tied solar electric systems.
|
