The Hydro Plant

The hydro plant didn’t start out as a hydro plant. In fact, it started out with wanting to have my own garden where I planned to grow herbs. I started out by digging post holes in an area I’d chosen near the inlet of a pond for access to water, and I toiled away, making a fence that I would surround the green house with.

The green house itself I made out of bent PVC pipes, which turned out not to be the greatest idea, as they have a tendency to bend in strong wind. Somehow, I had heard that a farmer I’d worked for before had lots of greenhouse tarp to get rid of, and she agreed to trade my labor in removing it from the greenhouse, which evidently she’d wanted to do for a while but really wasn’t a one person job, for the plastic itself. This turned out to be a good trade, and I happily built the structure. I covered the floor with black ground coverings from a different farmer I’d worked for who happened to have a huge pile of it after harvesting.

Things were going quite well until I had the idea of powering the greenhouse. It was around 400 feet from the nearest power source, and I decided that I really didn’t want to bother with running a wire that far. I had the idea of a wind generator, since that area tends to get quite a bit, so I went poking around in the old sheds around the farm.

Looking back, wind may have been a more sensible way of going about it since I can picture the dozens of fan blades out there that would probably serve well as wind turbines. What caught my eye instead though, was an old pump that had been retired from the hatchery since its bearings were evidently on their last legs.

After some experimentation, and a really excellent suggestion from a friend, I mounted it using a rectangular frame with long all thread attaching it, allowing it to adjust up and down. I waded into the pond, and I vividly remember trying to avoid the large leeches I could see swimming around my legs. After some struggle and frustration, I got it to mount onto the pond inlet–an 3 inch irrigation pipe with something like 150 feet of head water pressure. Then I cracked the valve and took out my multimeter to see what was going on. To my annoyance, I discovered that it was generating around 2 volts, so I decided to do some research.

Obviously (now at least) the motor I was using was a squirrel cage AC motor, meaning that it required power to create opposing magnetic fields in the stator and rotor so that it would spin. I did some more research, and found that what I was trying to do wasn’t as well internet-documented as I’d hoped, but I did learn that it should be possible to use the AC motor as a generator (at 110V no less) if I simply could “kick-start” the magnetic field. Looking back, probably the easiest way of doing this would have been to use a battery, but at the time I opted for a capacitor.

I wired the capacitor in line with the load, turned on the valve, and like magic, I was generating (a very unsteady) 110 volts of AC power. The motor in question was 1 hp, so I figured I could play with about 750 watts. The lights came on, I tried out a baseboard heater, and it worked! Unfortunately, the experiment ended up taking up all of my time, and I never planted anything. I aspire to have an excellent herb garden, powered by an awesome off grid renewable source and automated with interesting machines I'll make and program!