A total of 33,600 solar panels were used from JA Solar. The weight of one module is approximately 49.6 lbs. (22.5 kg). The modules were intensively tested and certified by various institutions, and must have the ability to withstand wind and snow load
Construction teams have put the finishing touches on what is now the largest solar park in the state of Tennessee. Volkswagen Chattanooga also becomes home to the largest solar installation at a United States auto manufacturing facility.
“We are proud to power up the biggest solar park of any car manufacturer in North America today,” said Frank Fischer, CEO and chairman of Volkswagen Group of America, Chattanooga Operations LLC. “The solar park is another proof point of Volkswagen’s worldwide commitment to environmental protection under its ’Think Blue Factory’ philosophy.”
During a recent dedication ceremony, a giant light switch was turned on to mark the official opening of Volkswagen Chattanooga Solar Park, built on Volkswagen’s compound in Hamilton County. Silicon Ranch and Phoenix Solar partnered to build and operate the solar park, which has made international headlines. The Chattanooga facility has been described by the U.S Green Building Council as “the world’s greenest auto plant” and the only auto plant to earn the LEED Platinum certification.
“Approximately 115,000 cubic yards of earth were moved to prepare the site,” said Simon Decker, business development and marketing manager USA of Phoenix Solar Inc. Founded in 1999, Phoenix Solar is a global leader in the design, construction, operation and maintenance of solar photovoltaic power plants, having installed or sold more than one gigawatt of capacity. Phoenix Solar Inc. is a wholly owned subsidiary of Phoenix Solar AG, headquartered in Sulzemoos near Munich, Germany.
“Equipment used to prepare the site included large machines such as Caterpillar motorgraders, Caterpillar track-type tractors, Caterpillar ejector articulated trucks, off-highway trucks and excavators of various sizes,” said Decker. “To install a PV system, Phoenix Solar Inc. used hydraulic rams and drills, telescopic handlers, power generators and sometime large cranes to get heavy equipment in place.”
A total of 33,600 solar panels were used from JA Solar. The weight of one module is approximately 49.6 lbs (22.5 kg). The modules were intensively tested and certified by various institutions, and must have the ability to withstand wind and snow loads.
The panels, about 3 by 6 ft. (1 by 1.8 m) in size, were manufactured in China and Mexico. Each panel is rated at 285 watts, with the system using a fixed angle array system at 25 degrees tilt. There are 3,360 panels per inverter made up of 168 strings at 20 modules per string. Power started being generated in November of 2012.
“Standard construction challenges required excellent site management and construction process management,” Decker said. “During the construction period, especially in the summer of 2012, crews encountered heavy rains, which created its own set of challenges. Our number one focus is always safety, and we strictly enforce these rules on our construction sites.”
The company played a crucial role in carrying out the massive project, from beginning to end.
“The goal for Phoenix Solar was flawless execution, and to provide a total solution. By providing the engineering, procurement and construction services, Phoenix Solar was the architect and general contractor, and also helped arrange the financing requirements for the project. The company’s technology neutral approach allows it to objectively provide the best solar solutions for our customers by integrating the best products with the highest cost-efficiency ration for a particular project. The selection of product depends entirely on site specifics and customer needs, as well as other factors,” he said.
Decker continued, “Since we don’t lay massive concrete foundations, but work basically in an un-sealed field, weather has an impact. For instance, during thunderstorms or other weather conditions that cause safety concerns, construction in an open field is halted until conditions are once again safe. Professional and experienced site managers, as well as overall construction management, successfully handled all the challenges, allowing the project to be completed on schedule.
Phoenix Solar mobilized its team in mid-summer, with construction completed by November 2012, followed by various testing protocols. A thorough pre-construction process required a considerable amount of time, as well.
Dr. Murray Cameron, chief operating officer of Phoenix Solar AG and president of U.S.-based Phoenix Solar Inc., said, “Phoenix Solar is extremely proud to have designed and built the largest solar electric photovoltaic plant in Tennessee for such a prominent global company. What is unique and exciting about this solar power plant is that Volkswagen has coupled clean electricity with energy efficiency measures in the factory to showcase how industry can make an immediate and positive contribution to protecting the environment.”
The Volkswagen Chattanooga Solar Park encompasses half of the 66-acre land parcel adjacent to VW’s manufacturing plant. The solar park’s solar modules were designed to produce 13.1 gigawatt hours of electricity per year. Officials say it’s the equivalent to the energy consumed annually by around 1,200 homes in the area.
The electricity produced from the solar park is expected to meet more than 12 percent of the energy needs of Volkswagen’s Chattanooga manufacturing plant during full production and 100 percent during non-production periods. The plant covers 1.9 million sq. ft. and employs more than 3,000 people who manufacture the Passat sedan. For Volkswagen, the solar park in Chattanooga will rank as the automaker’s largest photovoltaic installation worldwide.
VW says it will consume 100 percent of the electricity generated from the polycrystalline solar modules mounted on a Unirac racking system. Ten SMA inverters will convert the solar energy from direct current (DC) to alternating current (AC) to be used to power the electrical installations in the manufacturing plant.
Silicon Ranch, which develops and operates solar energy solutions, owns the solar park and will sell the electricity to Volkswagen under a 20-year power purchase agreement. The solar farm at VW was built by Phoenix Solar for Silicon Ranch, with VW leasing the land so that it never goes on to the public grid, but is directly tied into a substation and distribution system.
Matthew Kisber, Silicon Ranch president and CEO, said, “We are extremely proud of the VW solar park in Chattanooga. Who could have dreamed a generation ago that the day would come when a major automotive manufacturing facility right here in Tennessee would rely on the sun to help power up its production lines? This was truly an historic day for our state. It’s always amazing to watch a large solar project come out of the ground. Watching about a hundred workers drive mounting structures in the ground, assemble panels into large sections and then to see a big crane lift and place the panel units in place makes any grown man think back to his childhood days of playing with Legos.
“VW reached out to us in early 2011 to help them think through various options of meeting the LEED platinum requirement of 12.5 percent of energy use derived from onsite generated renewables. Phoenix Solar was an important partner in helping us to design an approach that would meet VW’s energy requirements in a reliable, cost-efficient manner. Once VW selected this option there was a tremendous amount of design and engineering that had to be accomplished to successfully integrate the solar farm into their operations. It was truly a team effort by all the stakeholders.”
Kisber continued, “VW’s solar park is the first ’behind the meter’ solar facility in the TVA Valley and required the support of the local utility, TVA and the city of Chattanooga to accomplish this project. VW and Silicon Ranch worked closely with all the stakeholders to ensure everything went smoothly. The support of the local leaders was important and everyone appreciated VW’s goal of being environmentally responsible and attaining LEED Platinum certification. This accomplishment is a great honor for the company and a great distinction for the City of Chattanooga.”
Not everything went according to plan, however.
“Being located next to a nature preserve means you have animals that stray over the fence into the solar farm. We also had to deal with Mother Nature. When we needed rain to assist the grass to take hold, we had drought and had to constantly water the seed, and when we needed dry weather for construction we were getting inundated with rain showers. Fortunately, Phoenix adjusted their strategy in order to minimize any delays from these situations and it came together very nicely,”?Kisber said.
Kisber says feedback so far has been very positive.
“Public officials in Chattanooga have called it another great example of what is going on in the city to make Chattanooga one of the most livable cities in the country. Media outlets around the country as well as globally have reported on the project. We also have had inquiries into our business as a result of this project from companies and utilities from across the country.
“As the price of solar generated electricity becomes more competitive with other forms of generation, deploying solar becomes both an economical and sustainability decision for a company. We have seen great interest by large electricity users after hearing about the VW solar farm to look at this approach. The financial advantages of a solar project like VW’s is that a company can lock in or hedge their long-term peak power cost for 20 years or more and save a significant amount of money over the contract term versus projected electricity inflation and therefore make this decision for both economic and environmental reasons. We’re extremely proud to have provided the solution that allowed VW to meet the onsite generated renewable power that is required for LEED Platinum. It’s a significant accomplishment for VW and for Silicon Ranch.”