The Tale of a PV Installation: Part 1

Back in July,I received a phone call from a couple interested in PV net metering. They were at a local HVAC business called Total Tech in Frankford, WV. As it turned out, they were finishing business concerning a geothermal heatpump system just installed at their new house. Wayne at Total Tech referred us as solar installers. I said sure, come on up, its only 9 miles up the road.
When they arrived we introduced ourselves and I began to query about their needs, desires and home site. This info gives me a better handle on what to present as options for system design.
The couple's names are Glenn Freeman and Susan Mitchell and they are in the process of moving to their new home on Muddy Creek Mountain in Greenbrier County, WV. They are retirees from New Jersey and was just a matter of a couple weeks before they say goodbye to Jersey and hello to West Virginia. It must have been a brave decision to make such a commitment. I think they will adjust well to the local mixed culture and what the mountains have to offer.
Anyhow, we sat in front of my computer and scanned Google Earth for their home site. The aerial photo was dated but we did find the clearing in the woods where the house sits now. I was a bit concerned about the ring of trees shading the array, so I suggested an on-site assessment.
Once I arrived, I was quite impressed with the style, quality, but appropriate size of the dwelling. Previously they had a solar consultant recommend siting, orientation, and roof pitch for the architect and builder. With the geothermal heatpump delivering 4kw of heat for every kw put in, they reduced their demand so that the PV array would provide a substantial contribution percentage-wise. We came to the conclusion that a 3600 watt array was a good starting point while having enough capacity built in so they could easily add 1800 or another 3600 watts over time. After taking some measurements for solar aperture, looking at wire run options, and roofing material, I told them I would be a couple days before presenting the results.
Back at the office, I plugged in the data into a program I assembled to provide performance, cost, tax incentives, and potential SREC value. SRECs stand for Solar Renewable Energy Credits and can be auctioned off to utilities in surrounding states. These utilities will pay up to $0.33 per kilowatt hour you produce instead of installing RE mandated content in their own grid.
Once satisfied with the general design and results, I emailed the docs to them. They soon called and said they were interested. Once I received an engineering deposit, I proceeded to create a detailed hard quote, wiring diagram, and agreement. I went to their place and discussed the details and answered questions. Upon signing the agreement, I requested a deposit and gave them the document to apply for net metering with Allegheny Power.
As soon as I got home the deal went into high gear. I researched availability of the parts through my various distributors to get the best prices and shipping costs. Once decided, I pulled the trigger and made the orders. It didn't take long for the smaller parts to arrive via UPS. The modules had to come by truck, so that took longer.
Once I had the mounting system in hand, which is a clamping system for standing seam roofs, I began to doubt whether they would work. So I drove back to the site and tried one on the seam. It didn't fit...crap. Instead of parallel, vertical seams, these had a truncated triangle profile. No amount of crushing or modification would make for a strong connection. Plan B.
I immediately ordered some UniRac SolarMount rails and clamps. These had to come by truck, so I put the hot rush on it. Meanwhile, I got a RMA to return the other mount system (at a 15% restock charge). The rails got here in a few days, no time lost. This was all my fault for not inspecting the seams closer. I figured standing seam was standing seam. These are the kind of gotchas that happen when you fail to focus on every detail even if you think you know what's going on.
By the time I had the rails and microinverters, it was blazing record hot for weeks around here. Add to that the brown tin roof and the installation windows were mornings only.
In a moment of inspiration, I thought why not populate the rails with the microinverters and roof anchors in my shop? That would prevent a lot of roof time precisely positioning the components on 130 degree tin. It took half a day on the workbench to mount the parts.
So we scheduled a rail install day and got them all up in a few hours. And they where pre-wired and pre-grounded boot!
In the meantime Joe, our licensed electrician, began to run wires in the house and mounted a breaker/disconnect box on an outside wall. He took the wires though the attic crawl space ready to punch through the roof once the modules are mounted.
My wife, Tenley and I delivered the modules on a Saturday since our truck had to go to a garage for a week. Susan and Glenn helped us lift them over the porch rail and made a neat stack. We strapped them together and covered them in case some rogue wind came through before the install.
I kept watching the NOAA weather forecasts online looking for a day with some heat relief. No, just relentless heat as far as you could see. I decided to break the module install into two mornings. Once we got there, there was dew on the roof (can't win for losin') After progressively toweling down the tin, we mounted the two grab ropes to assist our traction.
The first few modules established the flow required to be efficient. Like; where someone was at a given moment, what small parts in the belt bag, tools handy, knowing where the grab rope was, and getting the position of the first module straight and square. Our boots-on-the-roof guys were Joe the electrician, and Michael our electronics tech and fabricator. I was on the ground trying to think ahead about any glitches and providing parts, modules, and tools.
This is the end of part one, part two will be posted before too long.