So immediately (the next day) after teaching a 6 day workshop to build wind turbines, we started a 3 day workshop on tilt up towers. The first morning was spent talking about towers, why we need them... different types, and the serious problems and dangers with tilt up towers. Then we had a 180 foot met tower to play with (most of it anyhow) and had to fabricate a 40' tilt up tower for the 10' turbine that we'd finished just the day before.
While this was a 'hands on workshop' we just let George build the tower stub and do all the important welding because we wanted it to come out right.
George and Scotty just stayed to help for the first day of this... after that we were on our own. We had Chris Folk to help co-instruct this workshop.
Pictured above is the base of the met tower, leveled, on the site at the MREA campus.
We used 6 foot long screw anchors to hold this tower up.
It's a fair bit of work getting these into the ground (especially when you hit rocks) but not too bad.
We had a transit available to see that the side guy wire anchors were level with the base of the tower.
David was great, he was with us for Wind site assessment, building wind turbines, and building towers. He also spent 3 full weeks in Wisconsin... great help.
During our workshop the tail fell off the Jacobs 31-20 at the MREA. This happens every year or two... it's quite a pain. There is an 'upgrade kit' that increases the size of the bolts that hold the tail on from 3/4 inch dia to 1 inch diameter which will hopefully make this happen less frequently. Pictured above the tail is hanging from the springs. Both bolts are sheared off in the gearbox casting. And... it took off the spicket on the gearbox so all the oil leaked out... the top 20' of tower are covered in gear lube. Fun to climb (it's 120 feet tall)
More tower building, at this point they're assembling the tower and measuring/cutting guy wires.
This is inside the MREA's solar training 'roof' - it's got two systems, both grid tied. One is a solar ary that's grid tied through and Aurora inverter directly without batteries, the other system is is grid tied *with* batteries using Outback equipment. This 10' wind turbine will also be grid ties through the battery based system.
So they hired a crane to take the tail for the Jake down. Chris and Jenny climbed the greasy tower to help out with that.
There we've raised the short 40 foot tower without the turbine on it, and made adjustments. It worked out pretty well. This is just before lunch on the 3rd, and last day.
Clays car... picachu!
This is the winch that NRG supplies with their 180' tall met towers. We used it to raise this one.
Since this was a 'salvaged' met tower, it came with anemometers, wind vanes and data aquisition equipment. We installed two anemometers and a wind vane on this one.
The equipment we put there on the bottom of the tower....
There's the 10 foot diameter turbine we built just a couple days before this.
It went up with no problems. In fairly light winds we were seeing upwards of 600 Watts. It starts furling at about 500 Watts. Best wind we saw was about 16mph at 35'. This is also fairly turbulent wind, it was coming from the north, straight off a stand of tall trees. Most of the wind here comes from the west so hopefully it does better. We certainly don't expect stellar performance here on a 40 foot tower, but it's decent for educational purposes and close enough to the ground that folks can see the machine fairly well. It ran nicely, quietly and seemed to be reasonably efficient. Hopefully.. it'll still be there for anyone that makes it to the Energy Fair in a week and a half.
So that concludes our long/very busy stay in Wisconsin last month! What I did not include is stuff about the shocks that failed in our truck, the clutch that had to be replaced, two broken laptops.. the haunted house... the keg party with the students, etc. We drove back early the next morning (1200 miles) and I had 3 days to unload the truck, put my shop back together, order materials and get ready for the next workshop (here, at my shop) that started .... 3 days after we got home! More to come...
