July 2005

While July has come and gone without a report from me, it's not for a lack of progress at the ranch. With the impending wiring of the house, it was necessary to move the batteries and inverter panel, the heart of our off-grid photovoltaic system from the cargo container into the utility room in the house. The challenge is weight - the two batteries weigh 1300 pounds each and the inverter panel is just over 400 pounds. One of these days I'll write a web page describing the power system - all the components and how it works.

Here's a shot of one of the batteries. The steel case (about 100 pounds) contains 6 2-volt lead-acid cells, much like a car battery, only MUCH larger. Each cell weighs about 200 pounds. The vendor's recommended procedure involves lifting each cell from the case, moving it to the new location, moving the case, then installing the cells.

With only Rich, Ron, me, and Elaine, we weren't about to carry these cells the 100 feet from the cargo container to the house.

As you might have already guessed, the answer is the Gehl, again. I welded up a "stinger" (or boom) for the Gehl, which attaches to the quick release plate in place of the bucket. We put a hook in the end of the boom, placed a lifting strap across the battery terminals, and moved each cell, one at a time. I found the whole process pretty nerve-racking, when one considers the injuries that would come from spilling the quantity of acid contained in a single cell.

I drove the Gehl while Ron (Rich's brother, another member of the AARP construction crew) kept a hand on the cell to prevent swinging. The lack of level ground, as well as the need to turn 180° didn't make life any easier.

We "landed" the cells right inside the front door and moved them with a hand truck to stage them until we had the case empty and moved. Once inside, we used a hydraulic shop crane (barely visible between Ron and Rich) to lift the cells into the case. This was a pretty tricky maneuver since the cells aren't rigid and puff out when lifted. This meant getting the last cell into the case was a very tight squeeze.

The inverter panel was moved in much the same way - carried to the house on the Gehl, then lifted and moved with the shop crane. We held it in place with the shop crane while we bolted it to the wall.

The next day we finally got to work on the shower pans. The first step involves creating a sloped base above the concrete slab, so that water will run to the drain. We used soil cement made from the local earth (mainly sand) plus portland cement. The resulting color has everyone smiling - it looks like a giant slab of chocolate fudge. The block of wood on the drain is the gauge that marks the slope from the edge to the center. Just place a level on the block and measure to the edge of the pan. When it's level, you have the right slope.

The next two weekends were devoted to permanent installation of the photovoltaics and wiring them in place.

The first step as to dig a hole 30" in diameter, 36" deep to plant the pole into. The pole is 6" schedule 40 steel pipe, 10' long. This is close to 200 pounds of steel.

Once staked into place, a mix of soil cement fills the hole. Elaine got a cement mixer for her birthday last year (honest!) which came in very handy. It took quite a few loads, but it beats mixing by hand.

I did the first pole, Ken Bergeron mixed all the concrete for the second.

I assembled the pole mount frame on the ground, then lifted the whole thing in place with the Gehl. Each panel was then lifted into place and bolted.
On the second unit I got cocky and bolted the panels in place on the ground and lifted the complete assembly in place, with Elaine, Ken, and Teresa manning ropes to guide the assembly. We succeeded with no injuries or damage, but not without a certain level of "excitement' along the way. We still have to move the third panel from it's temporary location to the permanently fixed third pole and will have to decide if we can stand a similar level of excitement.

 

The unit closest to the house has the combiner panel which contains circuit breakers to protect the wiring to the house. A 1" conduit carries 2 complete circuits to the house, while 3/4" conduits branch out to the other poles.

During this period the plumber, electrician, and mechanical (heating) came and completed the "top-out" phase. All the wiring and plumbing inside the framing has been completed and the framing has been inspected (and passed).

The last weekend in July featured a forest fire in Corral Canyon, which is one canyon over from us (we're in Caņada Ojitos). During the day Friday we watched the tanker planes pass overhead, then saw them on their return to the north, presumably to El Vado reservoir where they filled up. Early Saturday morning we ran into a fire crew while we were driving to the ridgeline. They described the fire as a "sleeper', presumably triggered by a lightning strike 5 or 6 days earlier. The fire was contained in a 5 acre zone and the fire crews were mopping up. As we drove home later that day, we got to see the helicopter filling it's bucket and flying back to the fire line. The bucket carries about 100 gallons of water and the round trip from fill-up to fire line, and back to fill again took about 2 minutes.