I’ve been doing a lot of thinking lately about building some type of a wind turbine solution in hopes of eventually taking my detached garage off of the grid. Being in the San Fernando Valley we get a fair amount of afternoon wind that can be utilized by such a device. I did some testing with a traditional turbine, which showed some potential, but I eventually decided that a VAWT (Vertical Access Wind Turbine) would be the best option. The reason I came to this decision is because of how the wind swirls in from so many directions around my backyard, as is seen by little makeshift cardboard wind direction pointer.
I had mentioned before that I was working with pvc tubing and 5 gallon bucket lids as the materials of choice for my contraption – well forget all of that. It wasn’t turning out to be as practical as I had hoped. I was trying to use easy to find and cheap materials for the project but I just couldn’t seem to find a good solution for attaching the blades to the lids. I ended up going to my local electronics junkyard (Apex Electronics – amazing place) where I found literally hundreds of wheels from electric scooters that would be perfect for the blade mounts. Unfortunately the wheels are only about 9″ in diameter, but they are good enough to use for my prototype VAWT. I bought four of them at $5 each, which was a little more than I wanted to pay but still within budget and they would end up making the assembly process much easier (even more than I had imagined – as you will see later). I only needed two, but as they say in the movie Contact – why build one when you can build two for twice the price.
Today I started the assembly process. A month or two back I bought 2 – 10 foot long 2 inch diameter pvc tubing. I cut the pvc tubes into thirds (i.e. 3 feet 4 inch long each) and then cut them in half, which left me with 12 – 3 foot 4 inch long “blades”. As luck would have it, the blades fit very snugly between the spokes of the wheels, which meant that I didn’t have to use any fasteners at all. Here’s a grainy phone picture of the blades set in the spokes:
VAWT blades wedged snugly in the wheel spokes. Click image for a larger view
The hardest part to this whole process was attaching the blades to the second wheel. Once I got that accomplished though then all I needed to do was build a quick frame to mount it in, which was made from scrap wood I had laying around:
Completed prototype, with my dog Loki running by trying to generate a breeze to start it moving.
So it’s completed and ready to go… but there’s no wind. There’s a storm heading in to SoCal tomorrow that’s supposed to bring lots of wind with it so hopefully I’ll get some decent feedback on its performance. I already have some doubts about how efficient it currently is, but I also have some improvements I’m thinking about as well. No matter how good or poor it performs, I’ve only used about $15 in parts on the project so far – 2 x wheels @ $5 each and 1 x 10′ @ 2″ diameter pvc at about $3.50 each. I’m going to use the rest of the parts for a second VAWT eventually.
UPDATE: I cleaned up my math a little – I was a bit off on the tube sizing and the amounts.