What Winter Hath Wrought

Every winter brings about some damage to the waterline for the hydroelectric turbine, a/k/a the penstock.  Usually this is because a tree branch has fallen on some of the 1100′ of 2-inch Schedule 40 PVC, which is cheap but gets really brittle when cold.  I knew from the very beginning that replacing some of the PVC every Spring would be an issue but just accepted it as the cost of doing business. Last year was great, I had to replace and patch only two little sections.  2015 was the worst as I had to replace 600-feet of pipe.

Except for the last thirty feet all of the penstock is above ground.  I did originally get an estimate to burying the entire penstock well below the frost line, but the >$75k+ price tag was a bit much.  My hydroelectric system is more of a hobby than anything else, at least until the EMP or CME or some other grid-down calamity, so that wasn’t in the cards.

A shredded section of the penstock just before the ice storm.

This damage was peculiar because it was a compound spiral fracture which is only supposed to happen as a result of water freezing in the pipe and bursting it.  Since I drained the system in November this damage was a head-scratcher.  I am not looking forward to surveying the entire length of pipe once the snow and ice are gone.

I am now rethinking the penstock altogether.  Rather than sticking with PVC I am going to check into industrial irrigation polypropylene line which is continuous and much more forgiving to the forces that bust the PVC.  Since a pressurized/enclosed water line can run down to about -15 degrees maybe I could even keep it running year-round.

Stay tuned.