The Electrical Worker online
April 2016

The St. Louis Swedish Solar Super Roof
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Four miles due west of the St. Louis Arch is a big box store unlike any other in the state of Missouri.

Most big box stores are cookie cutter jobs. A vast indoor space is sandwiched between a concrete slab and a metal truss roof and surrounded by three concrete and one partially glass wall. Electrical work is straightforward, heavy on industrial lighting and easily handled by a handful of electricians over a few months.

"We typically bang out a Target with six members in six months," said St. Louis Local 1 Business Agent Tim Murray. "It isn't as simple as following directions with cartoons on it, but they are familiar jobs using routine skills."

But the new St. Louis Ikea is a showcase of the commercial electrician's art. It took seven signatory contractors nearly a year-and-a-half to build the temple to veneered plywood and Allen wrenches. The Swedish behemoth wraps dozens of life-sized dioramas of modern life, like scenes from the natural history museums, inside its blue and yellow walls. Then there is the towering warehouse, the lingonberry-and-meatball-scented restaurant, and high over the heads of the browsing masses, members of St. Louis Local 1 built one of the largest solar power generating stations in the state and by far the largest built on a commercial rooftop.

St. Louis is part of Ikea's corporate goal to be energy "independent" by 2020. This is the 42nd solar project for Ikea in the U.S. with many done by IBEW members. Solar panels are in place at nearly 90 percent of its U.S. locations. Ikea has installed more than 700,000 solar panels across the world and, an Ikea spokesman said, owns approximately 157 wind turbines in Europe and Canada, with 104 more being built in the U.S.

"This project was a microcosm of everything we know about commercial retail construction, especially solar," said Murray of the 1.3 megawatt, 260,000-square-foot solar array that will produce 1.8 million kilowatt-hours of electricity annually for the store, the equivalent to reducing 1,227 tons of carbon dioxide.

And that was less than 20 percent of the total man-hours on the project.

"We normally finish large retail projects with a half-dozen workers in six months. We had double that for twice as long because of the complexity," said Local 1 member and project foreman Chris Thomson. "I am proud to say doors still opened as planned on time and on budget despite enormous challenges."

For the Ikea project, Aschinger Electric had 15 members working full out for five months, 20 at the peak.

Solar power is not a big business in Missouri yet, Murray said, and most jobs that do come up are for two or three wiremen for about a fortnight.

"We are the most experienced solar installer in St. Louis and this blew everything we've ever done out of the water," Thomson said.

Aschinger, one of the largest woman-owned contractors in the state, also exceeded workforce diversity standards. Any construction project using city funds or receiving city benefits (in this case incentives) requires 25 percent of the workforce come from historically underrepresented communities, 20 percent must be local hires and 5 percent women.

"We had to meet some pretty aggressive numbers and we creamed them. Knocked them out of the park," Murray said. "We doubled the women, and far exceeded local hires."

Possibly the biggest challenge was installing a system from a manufacturer that Aschinger had never used before, designed for a roof that ended up looking nothing like the drawings that had been used to order it.

"The general contractor had no experience with solar installs," Thomson said. "There were substantial changes to the original design that affected 95 percent of the modules. This was no cookie cutter job."

Skylights were turned 90 degrees out of orientation. Two-foot high expansion joints were not marked on the plans. And unlike most of the solar rack-and-panel systems Aschinger had used in the past, very little of the system they used was modular.

Most other systems Thomson had seen allowed the work to be done in stages. First the racks were built and positioned. Then wires were laid out for the individual panel and inverters — known as modules — before the panels were brought up and bolted into place.

"The big advantage is you can get everything in place without crawling around on the ground and make corrections before everything is locked into place," Thomson said.

But the system they were installing required every rack and module to be completed before moving onto the next, and each one connected and electrically balanced with the others. Only two of the 30 went in as they were designed on the plans.

"As we reconfigured everything, we had to recircuit the whole system without under or overloading it, and because each module was connected to about 11 others, there was no way of going back to fix it if there were any mistakes," Thomson said. "That requires a brain and an experienced one."

Despite the challenges, or more likely because of them, Thomson said the install crew was especially proud of the finished product, delivered on time and on budget.

"This shows the value of using the best trained electricians in the world," he said. "From the construction wireman to the apprentices to the journeymen there was nothing we didn't handle in stride."



The largest commercial rooftop solar installation in Missouri was installed by members of St. Louis Local 1. Mike Seger, left, is project manager for Aschinger Electric, with Local 1 member and project foreman, Chris Thomson.