Solar Electric Project

charlz · Sep 1, 2008

My experience is similar to defective. 'standard' shop vac sucking 'pull string' (bailing twine) through 3/4 up to 4 inch conduit. All low-voltage stuff but if pulling enough through a big conduit we would use the pull string to pull in a rope and use that to pull the cable.

Network cable is sensitive to stretching so you can't pull very hard. Lots of pull boxes in the conduit runs which makes it easier to pull by hand but takes longer to pull in a long run. Personally I like to stay away from lube unless absolutely necessary. Some of that stuff sets up like concrete after it dries out. When you are pulling slack at one pull box to feed down the line if the cable is lubed it is one huge mess.

mjncad · Sep 14, 2008

Hayden:

I don't know if you caught Discovery Channel's "Project Earth" series last night; but they were reviving the 1980's concept of orbiting power plants that would harvest sunlight with solar cells and convert the energy to microwaves to be beamed to earth.

Now you may know this; but they experimented with a solar cell that had a Fresnel lens over it. The Fresnel lens was bent in a similar shape to a barrel roof on a building. They took two solar cells, one unmodified and the other with the Fresnel lens and sent them to near space hanging from a weather balloon. The interesting part is that the Fresnel lens concentrated 8-times more light on the solar cell, resulting in a 3-fold increase in power output.

If it works in space, it might be worth trying down here on the ground.