[David]

I'm no electrical engineer, but I do work for an electric utility so I was curious. I asked an electrical guy at work and he said it appears to be a power factor correcting capacitor bank that could actually be some benefit if you have some motors at home. He said a few of the guys that have pool pumps have built their own similar devices at home. He also said most A/C compressors with a 13 SEER or higher rating already have such circuits.

I have two pool pumps plus an air compressor so I may look into building something like this if I get bored.