Aspen plugs into more solar power
Primergy Solar developed some very workable solutions to deal with unique challenges on a 5 MW project near Aspen, Colorado, with nearby residents concerned about its visual impact.
By Robin Brunet
Developing solar power projects can be more challenging than it may appear. Project developers often run into permitting, developing and commercial challenges.
When all the stars don’t align, it’s common for companies to purchase projects that have been partly developed by other companies, to try their hand at resolving issues, achieving better outcomes than what was previously planned.
Such is the case with Primergy Solar’s solar project near Aspen, Colorado. This past October, the company announced that it had completed construction on the Pitkin Solar array, a 5 MW, 35-acre solar installation in Pitkin County, near the ski mecca.
The project is located near Woody Creek in the Roaring Fork Valley on land leased from the Aspen Consolidated Sanitation District (ACSD). The land was originally purchased by ACSD for its dry land farming operation, which put wastewater treatment byproducts to beneficial use.
Power from the project is being sold to Holy Cross Energy, an electric co-op serving almost 45,000 members in Western Colorado, under a 25-year power purchase agreement. Bryan Hannegan, president and CEO of Holy Cross Energy, told media that the completion of Pitkin “is an important step on our journey to 100 percent clean energy for our members”.
“We very much appreciate the efforts made by Primergy to work with Pitkin County to minimize the impact to the local community from the construction of this new source of clean and resilient energy.”
The project was originally owned by Renewable Energy Systems (RES) Americas, and Adam Larner, project manager for Primergy, credits the international green energy group “for bringing Pitkin to the halfway mark. It had identified the site, had almost completed planning approval via commission meetings, and had executed the all-important power purchase agreement.”
The achievements of RES were all the more noteworthy considering the project was considered controversial. Opposition came from residents of Woody Creek, the W/J Ranch housing development, and Brush Creek Village, who mainly objected to the visual impact the solar panels would have.
However, many valley residents supported the project (in fact, the idea for the solar array came from the communities served by Holy Cross, who voiced a desire for clean energy), and in November 2019 a special hearing of Pitkin County community development staff was held.
During the proceedings, board chairman Greg Poschman said he’d studied solar technology in the 1980s and identified the ACSD site as an ideal location for a solar farm back in 2013. At the time, he assumed the county might be interested in building a farm but couldn’t drum up any interest from officials.
Critics who insisted the solar farm would be an eyesore demanded that it should be hidden behind landscaping and berms (an ironic stance to take, considering the district had used the site for 30 years to dispose of treated wastewater). County planners even considered applying for a variance to increase the proposed berm height limit of four feet to 20 feet, to better block views from the Rio Grande Trail.
After six hours of hearings, the commissioners unanimously approved the project (and decided the berms wouldn’t be more than four feet tall after all), and media reiterated what was then the deal between RES, Holy Cross Energy, and the ACSD: the district would lease 35 of the 55 acres it owned southeast of the intersection of Brush Creek Road and Highway 82 to RES, to install 18,000 solar panels (a number that would subsequently be reduced under Primergy’s ownership).
|Primergy Solar has completed construction on the Pitkin Solar array, a 5 MW, 35-acre solar installation in Pitkin County, near Aspen. Primergy dealt with initial objections to a solar project by changing the design to a better ?approach with no grading, with less dust and less overall impact, and less equipment on site.|
The site’s former industrial use, coupled with the fact that it is under the flight path for Aspen’s airport, has year-round solar exposure, and is within half-a-mile of Holy Cross transmission lines, made it an ideal spot for the solar farm. The power generated would be transferred to transmission lines via an underground connector Holy Cross agreed to build, and the amount of electricity generated would power about 900 homes. In exchange for providing the land, the district would receive lease payments and a 33 percent energy credit from Holy Cross that would grow in future years and save customers money. Total project cost according to RES: between $6.2 million and $7.2 million.
Shortly after the November 2019 meeting, Primergy stepped in. “We think solar projects shouldn’t alter topography, and Pitkin, as it was previously planned, would involve 18,000 cubic yards of earthmoving,” Primergy’s Adam Larner says. “The more we studied the Pitkin project, the more we were convinced we could do it better. Plus, our approach would make it easier to get planning commission approval.”
The initial approval was before Primergy was involved; after Primergy was involved, there were three additional BCC (Board of County Commissioners) meetings where the company had to present its new “no grade” approach in order to get approval on that final design. This was followed by two more meetings to address community concerns that were further assuaged by Primergy’s approach.
So, while there was an initial approval, Primergy dealt with the objections by changing the design to this better approach with no grading, with less dust and less overall impact, and less equipment on site.
Specifically, Primergy’s approach would change Pitkin from a grading to a no-grading project, with no change in water flows. “That’s another undesirable aspect of grading: you never know exactly what the outcome of altered water flows will be,” Larner says. “Also, by leaving the topography alone, dust would be mitigated—which was important, considering the site was near the main highway to Aspen and homes were less than a mile away.”
Larner describes getting final approval to launch the project as surprisingly uncomplicated. “Everyone was pleased by the prospect of us generating no dust in a highly visual area,” he says. “Aspen is not a simple place to get anything approved, but one commissioner later told us that this was the first time a development proposal received so little pushback for its construction phase.”
Key to the success of the project was for steel foundations to create a flat surface upon which the solar array could be installed—and that posed a considerable challenge for work crews. “There was an enormous amount of rock and glacial till mixed in with the treated solid waste on the site,” Larner says. “That meant every foundation had to be drilled, and it was determined that we would have to drill 1,100 holes to a depth of about eight feet.”
|Primergy Solar opted for bifacial 440-watt panels from New East Solar Energy for Aspen’s Pitkin Solar project. The panels have specialized anti-glare components to cut down on reflected light for both planes flying over and for neighbors; plus they have an impressive 0.5 percent annual degradation over 30 years.|
Fortunately, Primergy had plenty of experience dealing with such physical circumstances, and on a much larger scale: for its ongoing Gemini project in Nevada (a $1.2 billion, 690 MWac/966 MWdc solar array undertaking), the company was obliged to drill 280,000 foundation holes.
As was the case with Gemini, Primergy relied on the expertise of former mining drillers to ably deal with the sensitive landscape. “Our crews were all ex-miners, one originally being from Pennsylvania, and they had gravitated into this line of work because it was more lucrative and far less dangerous,” Larner says.
“These crews tend to be nomadic, and the advantage of them working in this part of Colorado was that at the end of the day they could go fishing or hiking in the great outdoors.”
Down-hole hammer drills were the key pieces of equipment used for the foundation work, along with pile drivers, skid steers, and excavators (the latter used for cabling). “Altogether we had up to 85 people and five different subcontractors,” Larner says. “It took 45 days to drill all the holes.”
Primergy typically installs its solar arrays from the back to the front of any site entrance to keep heavy equipment away from the finished product, and Pitkin was no exception. “We worked from south to north, installing 13,700 panels in total,” Larner says.
Primergy sourced bifacial 440-watt panels from New East Solar Energy. “NE Solar is based in Cambodia, and after conducting tests we were impressed by the quality of their product,” Larner says. Made with selected materials and components to ensure longevity, efficiency, and stable outputs, the ZXM6-NHLDD144 monocrystalline modules (better known as Znshine Solar panels) represent a highly flexible solution for diverse installation types.
The panels also have specialized anti-glare components to cut down on reflected light for both planes flying over and for neighbors; plus they have an impressive 0.5 percent annual degradation over 30 years.
Primergy sourced inverters for Pitkin from Solectria, a leader in supplying commercial PV inverters for the U.S. “The company is based in Illinois, which we felt was important because inverters are the components of any solar project most susceptible to service issues. It would be easy to get replacement parts, plus Solectria is well known for emphasizing quality and value.”
Array Technologies were sourced for their single axis trackers, which are designed to withstand harsh desert environments and high wind speeds with a patented wind-mitigation system that does not rely on complex communications systems, batteries, or power.
The Primergy crews spent three-and-a-half months, from June to September of 2021, constructing and commissioning the Pitkin solar farm, and Larner notes that tie-ins were less than half-a-mile away.
“Also, we added 200 trees and bushes to the west of the site where a jogging and biking trail is located, to decrease visual impact. All in all, the project went very smoothly, our investment in community education paid off, and we worked in a spectacularly beautiful state.”
John Keleher, chairman at the ACSD, says Primergy “have been outstanding all around. Their patience and sensitivity to the land use review process was excellent. This solar project directly aligns with our purpose of protecting the environment. The power cost savings that result from our capital contribution will save ACSD customers money in the long run—and helps us directly offset the large amount of power
we consume providing advanced wastewater treatment for our