Seattle project produces solar-savvy graduates

A new PV array on the roof of a Seattle-area college is a clean-energy investment with a different sort of payback: solar-savvy graduates.

The Education Building at North Seattle College now sports a 7.4-kW PV system, its primary array perched atop a rotating armature that tracks the sun across the sky each day.

While the array will only yield a small fraction of the building’s energy needs, “power” per se wasn’t the point.
“This isn’t really about generating electricity,” said Mark Weber, faculty and program coordinator for the college’s HVAC and Sustainable Energy Program. “This is an educational tool for our students. It’s a dynamic learning environment rather than a static one, where we can do all sorts of experimentation with module orientation, the effects of weather, all kinds of things.”

About half of the $75,000 system cost was funded by a grant from the Portland, Ore.-based Bonneville Environmental Foundation, which promotes renewable energy and resource conservation. The college made up the balance.

Artisan Electric of Seattle was selected from among three local installers submitting proposals. The combination of a solar tracker, 3-phase output and a mentoring component for students set Artisan’s design apart in the bidding process.


An APS YC1000 is installed on the underside of the array.

The primary array includes thirty 240-watt modules by Talesun. A secondary, fixed-position array of three modules is planned to serve as a system “control,” allowing students to compare the output of the two designs – one that continually aligns itself with the sun to optimize solar harvest, the other pointing eternally south.

Anthony Sarno, system designer for Artisan Electric, selected APS YC1000 microinverters for their true 3-phase output. The APS units tied into the building’s 480-V circuit without the need for step-up transformers, in an electrical room that would have been too small to accommodate a central “string” inverter.

“When I saw the 480 panel, the light bulb went on,” Sarno said. “I saw potential savings by using the YC1000 microinverter, and there was an element of allure to having a cutting edge product in the mix.”

APS and its Washington state distributor, Blue Frog Solar, provided the YC1000 microinverters below cost as a donation to the college.

“The chance to help students learn about PV system design and train for the renewable energy trades was compelling,” said Paul Barlock, APS Senior Vice President. “This project is a showcase for true 3-phase microinverters in a commercial setting, but the fact that it’s in a college environment provides much greater benefit still.”

Tracking the sun
Marketed under the name SolarTrackr, the “smart tracking” system was designed and fabricated by Wovn Energy of Seattle.

Putting the 2-ton apparatus atop a three-story building added a layer of design complexity, the first question being whether the roof could support it.

The structural engineer responsible for the building’s original plans was still in practice, Sarno said, and provided new calculations proving that the roof could bear the load.


The team from Artisan Electric begin attaching modules to the tracking system’s steel armature. The array will rotate and incline to track the sun through the sky. Photo Credit: Wovn Energy

Next came the question of ballasting. Fortuitously, the rooftop featured several low concrete parapets that extended down through the building to the ground. These walls became the foundation for the massive steel armature that was assembled over five days in March.

The completed array rotates around a circular steel rail, inched along by a small electric motor, while a second motor and a piston provide inclination. Together the two motors draw about the same power as a 100-watt light bulb, said Alan Tilley, Wovn Energy vice president and tracking system designer.

Wovn’s solar tracking software uses algorithms provided by the National Renewable Energy Laboratories, and also accounts for local weather and atmospheric conditions to optimize the array’s positioning. Solar harvest is projected to be about 45% higher than a static array. Computer control can be manually overridden so students can set the array to other positions for research and data collection.

“Compared to a static system, this thing has so many more opportunities for learning,” Weber said, “not just for solar, but also for engineering. The control system is going to be way cool to play with. We can bring in people from other disciplines, not just our program.”

The founders of Wovn Energy set out on a mission five years ago to provide distributed-energy management systems, out of which the SolarTrackr system evolved, Tilley said.

The product was designed to offset the then-high cost of modules, allowing buyers to achieve greater yield from a smaller array, Tilley said. As module prices have come down, the SolarTrackr is now marketed as a way to make full-sized arrays more powerful still.


Workers assemble the circular steel track on which the 30-module PV array will rotate at North Seattle College. The tracking system was designed and fabricated by Wovn Energy of Seattle. Photo credit: APS USA

The North Seattle College project was the company’s fifth installation, and the first on a rooftop. The biggest challenge previously was a ground mount perched on the side of a mountain.

“That one was a real bear,” Tilley said. “This one is tame by comparison.”

Wovn expects to have about 15 installations in its portfolio by midyear, he said, with two more already underway in the Seattle area.

For students, by students

Befitting an educational venture, the North Seattle College project engaged students from the start.
Students from nearby Shoreline Community College, which offers a two-year degree in Clean Energy Technology, were brought in to do a solar site assessment. Their report became the baseline against which formal proposals were evaluated.

North Seattle information technology student Christoph Strouse was a key member of the solar project team, and system designer Sarno is a graduate of Shoreline program.

“Artisan kind of plucked me out of the program, and things have fallen into place very well,” Sarno said.
Because the array shoots up 25 feet above the roof of an already tall building, it has become a billboard of sorts for North Seattle College. The array is visible from adjacent neighborhoods, from a popular commercial center a mile to the east, and to passing motorists on the busy I-5 freeway.


Alan Tilley, engineering vice present and tracking system designer for Wovn Energy. The North Seattle College project is the Seattle company’s fifth installation. Photo Credit: APS USA

It is also becoming both a valuable asset and a recruiting tool. Weber said the college is in talks with other area schools and a major research university to share solar performance data collected by students. The colleges are also beginning to collaborate on programs to meet the evolving demands of the clean-energy and construction industries.

Weber and Strouse envision a hybrid program in “High Performance Building Technology.” Students might someday take electronics and IT classes at one school, HVAC or facilities management at another, and PV system design at a third toward an integrated degree.

Having an advanced solar installation could make North Seattle College the program’s logical hub, and the investment is already paying off for students.

“I’m very lucky to have been here at the right time to be a part of this team and experience this project from paper to completion,” Strouse said. “As a learning experience, it doesn’t get much better than this.”

Project Details
North Seattle College 3-phase 7.4-kw PV system
Designer/installer: Artisan Electric, Seattle
Tracking system and racking: SolarTrackr by Wovn Energy, Seattle
Microinverters: 8 APS YC1000 true 3-phase
Monitoring: APS Energy Communication Unit/Energy Monitoring and Analysis software
Modules: 30 Talesun 240W

World’s largest true 3-phase microinverter installation powered by APS YC1000

The groundbreaking YC1000 microinverter from APS will power a milestone true 3-phase installation going into service in China’s Zhejiang Province this week.

More than 1.4 MW of the total 8.13 MW project will be generated using APS microinverter technology – earning it distinction as the world’s largest true 3-phase microinverter installation.

The project at the Haining Hailide Jianshan factory began development four weeks ago, and is planned to join China’s national power grid on Dec. 30.

The installation includes 1,200 APS YC1000 microinverters. Now available in all APS markets worldwide, the YC1000 is the industry’s first true 3-phase microinverter and handles up to four modules per unit, simplifying PV system design and installation while significantly lowering balance of system costs.

Independent output and tracking optimizes the performance of each PV module while minimizing shading effects across the whole array.

APS microinverter technology increases array output by 5-25 percent compared to conventional “string” inverter systems.

Using the integrated APS Energy Communication Unit (ECU), Haining system managers will be able to track power output, voltage, current, temperature and other performance data of every module in the array.

The completed project will provide approximately 8.14 million kWh of energy per year, saving nearly 3,000 tons of coal while reducing CO2 admissions by more than 700 tons. Over the plant’s projected 25-year lifespan, the reduction in coal use and carbon and sulfur dioxide emissions will be multiplied many times over.

The year 2014 has marked the first widespread development of distributed PV power throughout China, an effort vigorously promoted by the Chinese government.

The electricity generated by the Haining system promises a strong economic return for investors, powering the factory even as it protects the local environment and promotes APS 3-phase microinverter technology in the robust China market and worldwide.

APS microinverters power new community solar project in Spokane

APS dual-module microinverters power a prominent new “community solar” installation in Spokane, Wash.

“It’s producing extremely well,” said John Francisco, chief of energy resources for Inland Power & Light, as he monitored the output of the new 30kW installation outside the utility’s office. “We were fortunate to finish construction and energize the array during the span of several cloudless days so we could get a good feel for the performance of the array.”

The ground-mount array sits in view of passing motorists on I-90, a prominent display of APS microinverter capability.

It’s the first significant venture into solar for Inland Power, a member-owned utility serving about 39,000 residential and commercial customers in 13 counties in eastern Washington and northern Idaho. Founded in 1937, it is the largest electric cooperative in Washington.

brimma2-smThe full cost of the system was funded by participating utility members, who were given the chance to buy shares in the system and reap the financial benefits of solar investment.

The project is also a showcase for Washington’s thriving solar industry. The installation includes 56 APS YC500-MIW microinverters distributed by Blue Frog Solar of Poulsbo, 112 PV modules by Itek Energy of Bellingham, and racking by SunModo of Vancouver, Wash.

The installation was completed in late August by Brimma Solar of Vancouver, the winning bidder among three firms that vied for the project.

John Harley, Brimma Solar vice president, said the project’s impact extends far beyond the customers who will benefit from its power production.

“When a utility installs a system, it helps promote solar for their customers,” Harley said. “Customers with solar, or thinking about installing solar, feel comfort when they know their utility supports solar.”

For Washington solar manufacturers, the project is also chance to demonstrate the high quality of solar components being produced by local industry.

“We think this is exactly the sort of project our legislators hoped to encourage when they envisioned community solar,” said Tim Bailey, Blue Frog Solar co-founder and APS microinverter distributor. “To see locally made solar equipment in a showcase project like this is tremendous, and really shows solar’s success in Washington.”

Inland Power is the fourth Washington utility to develop an array under the community solar model, according to Phil Lou of the Washington State University Energy Program, which tracks the industry. About 30 community solar projects totaling 872 kW capacity have been developed statewide.

Those have supplemented residential and commercial solar installations in the growing industry. About 8 MW of solar capacity was installed across Washington in 2013, a 54 percent increase over the previous year.



In 2005, the Washington state Legislature enacted solar production incentives to promote the development of alternative energy sources including solar and wind.
Homeowners and businesses that install a solar system can earn a power rebate of 54 cents per kilowatt-hour of energy they put back into the grid – a “distributed generation” model – up to $5,000 per year.

The Legislature later extended the incentives to “community solar” projects, encouraging utilities and local governments to add clean energy arrays to their own production capacity. The sponsoring utility earns a state tax credit that is passed along to participating customers in the form of production incentives.

Inland Power already had about 80 customers with residential solar arrays. The utility also had a modest, 2.24 kW ground-mount array of its own that went up when it built a new office five years ago.

The opportunity to build a larger, community array on the same property made financial sense to the utility, and was met with strong support from members when it was proposed.

“We wanted to expand solar participation, and community solar was an excellent avenue due to the low entry cost to each participant and the very generous state incentive structure,” Francisco said.

With the array now up and running, members got the chance to buy in. Shares were made available to Inland Power members at $300 each, with a limit of 10 shares per member. A total of 526 shares were available.

The shares were priced high enough to keep the total number manageable by the utility, and low enough to allow participation even by customers of modest means, Francisco said.

Because of strong demand, Inland Power offered the shares to members through a lottery in October.

“We were way oversold, and the lottery was a fair approach to allocating the available shares,” Francisco said. Inland had approximately 1,300 members submit their names for the lottery, and 87 members were drawn.

Solar shareholders will receive the benefit of net metering, that is, the positive difference between their own power consumption and what their portion of the community solar system generates. They will also see a pro rata rebate from Inland Power per kilowatt hour of power produced.

“We are excited to help a broader section of our members enjoy the environmental benefits of solar power, contribute to our state economy by supporting in-state manufacturing and take advantage of the state-sponsored incentive program for community solar,” Francisco said.

Francisco said the project is already a success for Inland Power customers. If the utility is seen in the vanguard of community solar in Washington, that’s okay too.
“We’re doing this for the right reasons, but it’s nice to be recognized,” he said. “We believe in it, otherwise we wouldn’t do it.”



APS microinverters the only solution for Hawaii shopping center

When owners decided to renovate a shopping center on the island of Oahu, Hawaii, their plans didn’t stop at the ceiling.

The expansive open rooftops at the multi-building complex offered perfect platforms for a new solar system to take advantage of the islands’ famous sunshine.

The 30-year-old shopping center on the Kamehameha Highway is an important commercial hub for the community, anchored by mainstays including Ross Dress For Less, 24-Hour Fitness and Foodland groceries. The center also offers an array of professional and financial services, popular retail outlets and eateries.

The project has become an ambitious proving ground for commercial solar power, and for APS microinverter technology – in terms of scale, and also because of Oahu’s nonstandard power grid voltages.

Three-quarters of the project operates at 277V AC, significantly higher than the 208V three-phase systems and 240V residential voltages standard in the continental US.

APS microinverters’ chip-based architecture allowed each unit to be specially programmed to easily accommodate the higher grid voltage – a flexibility built into each APS unit and unmatched by any other microinverter in the market.

“We’re the only microinverter that would work here,” said Tommy VanCleave, technical support manager for APS America. “We offered a technical solution that made this installation possible.”

In terms of scale, it is by far the largest domestic application of APS microinverter technology.

The system includes 3,046 PV panels by ReneSola, each offering up to 305W power output. The panel array is served by 1,523 APS YC500 dual-MPPT microinverters –- one for every two panels, representing significant cost savings and installation ease over other alternatives.

The proprietary APS microinverter design was also ideally matched to the large, 305-watt PV modules, and the greater AC output offered investors a significant ROI advantage over other inverters on the market.

Total system capacity is 929 kW, supporting the shopping center’s operations and putting power back into the local grid. Mall patrons are benefiting from Hawaii’s most abundant resource: the sun.

The project is now roughly 80 percent complete, with all 277V systems and one of two smaller 208V rooftop arrays now producing power.

The APS Energy Communication Unit software will provide real-time graphical monitoring of each rooftop system and individual PV modules within each array.

The early returns are strong — the system is actually outproducing the agreement between the shopping center and Pacific Power Renewables, putting more energy back into the system than originally envisioned.

“Overproduction – that’s great,” VanCleave said.