Universities go solar-with solar gardens
Michigan power producer Consumers Energy has been able to meet their customers' interest in solar power by building two community solar projects, a three-MW solar garden at Grand Valley State University and, more recently, a one-MW facility at Western Mic
By Diane Mettler
Consumers Energy, a Michigan energy producer was receiving requests from customers who wanted to invest in solar energy. They were ordinary people who were not in a position to install solar panels but still wanted to reduce their carbon footprint.
What does an energy producer do? Find a way to build community solar projects.
"We worked with the Michigan Public Service Commission and got authorized to build up to 10 MW of community solar," says Emily Warners, project engineer at Consumers Energy.
The plan was for the funding to come directly from Consumers Energy customers through subscriptions. Customers could purchase one or more blocks of solar power at a cost of $10 per month, per block (a half-kilowatt). There would be a return on the investment as well. Once the solar facility was generating electricity, the customers would receive a credit on their bills that reflected their share of the generated electricity's value.
It looked to be a good fit for Grand Valley State University, in Allendale, Michigan.
"When I heard that Consumers was looking at adding solar and had this concept of solar gardens, I explained that we were looking for a potential solar project—one that perhaps we did not want to own and operate but would want to buy units of energy from," says Peter Strazdas, associate vice president of facilities management at Western Michigan University (WMU). "So we got involved early on."
"Western bought one megawatt of subscriptions. That helped us get started," says Warners. "After that, we started marketing with billboards, emails, and mail inserts in people's bills."
The subscriptions allowed Consumers to build the first three-MW Solar Garden at Grand Valley State University followed by the one-MW facility at Western Michigan University in Kalamazoo, which was completed in August.
The WMU solar garden was ideally situated on an active prairie field outside the engineering building, where it left the prairie unaffected. The project's location next to state highway US 131 allows hundreds of thousands of people to see it each year.
"We were interested in showing our relationship with renewable energy to the public," says Strazdas. "So we leased the land to them for a 25-year agreement."
During the construction, there was a lot of interest from engineering students next door. "That was another advantage of the project," says Warners. "The students got to learn more about solar, and we had prepared our construction managers and workers for those questions."
Consumers used 4,000 Suniva 330-watt solar panels and SMA inverters for their value and effectiveness.
Warners says the Suniva solar panels perform very well in different weather conditions. "Even on a cloudy day, as long as there is light outside, they are still producing power. A lot of people ask about snow. If it snows at night, the panels actually heat up in the morning when the solar panels start to produce, and the snow kind of melts off. So they are very low maintenance."
Although one would think building on an active prairie might come with challenges, it went quite smoothly.
"We're letting the prairie grass grow between the panels, and we also raised the panels up a bit so we could have prairie grass grow like it once was," explains Strazdas.
|Western Michigan University is serious about solar power. In addition to its participation in a solar garden, students from the university have entered solar-powered cars in the annual American Solar Challenge.|
Warners says preserving the prairie is something Consumers is quite proud of. "Prairies are a great way to mitigate soil erosion, which is another great environmental impact. We worked a lot with them [Western] to keep that going and to keep that vitalized, which worked out great. We both ended up winning on that."
Strazdas and the others at the university were initially apprehensive there might be a negative response when people saw a solar array instead of grass. They need not have worried.
"Mostly we've been getting positive feedback. I think it's that visual relationship between the massive solar garden and the College of Engineering. When you have thousands of vehicles going up and down this highway, it draws that connection of our institution being more sustainable. We're very proud of that. We have a very good track record of being a notable, sustainable university."
One of the unique aspects of the two solar projects was that Consumers Energy also provided both universities with an educational grant.
Part of the grant was to have the engineering faculty and students design a very small solar garden of their own. Western Michigan University installed two small experimental solar panel arrays for the engineering students to study.
"The first solar panel array has 18 Suniva 275-watt solar panels. They are connected with SolarEdge, which uses optimizer modules with a SolarEdge inverter. Total rating at 275 W for 18 panels is approximately 4,950 watts," explains Dr. Bradley Bazuin, associate professor at Western Michigan University. "The other system consists of 45 solar shingles. They are from a Michigan company, Luma Resources, that installs the solar shingles and also metal roofing systems—a high-end roofing system with solar capability. The shingles are approximately 60 watts apiece. That one has an SMA inverter, with both inverters feeding directly into the College of Engineering and Applied Sciences." They used racking from Mounting Systems Inc. for the project.
The university subcontracted a local company, Solar Winds Power Systems, owned by Mike Linsea, to install the solar arrays. "We prepared a technical concept of what we were interested in, and then we had local companies bid," explained Bazuin. "We wanted as much as we possibly could get for the funds that were available in these two different solar arrays with two different capabilities. Mike Linsea was the contractor who was selected, and he has done a wonderful job for us."
The second part of the grant involved reaching out and teaching the public.
"We will receive $20,000 for six years to do educational outreach to the community, governments, firefighters, and organizations that could interact or have control or interest in solar energy, as well as residential consumers. We also do the normal types of educational activities at the college level and K-12," says Bazuin.
|The Western Michigan University solar garden is ideally situated on an active prairie field outside the engineering building, where it left the prairie unaffected. The project's location next to state highway US 131 allows hundreds of thousands of people to see the solar garden, and solar power at work, each year.|
Bazuin has already given a couple talks to firefighters about the importance of understanding solar energy and solar systems with regard to the dangers they can pose when encountered.
"If you look at each one of the panels—our panels are about 40 volts—you're right at that borderline of being able to shock yourself to death. But that's a single panel. Once you put 18 together, or even split that into two sub-grids, you've got significant current that could potentially do serious damage," says Bazuin. (For anyone interested in his talks, he has posted them on the university website.)
Bazuin has also given tours of the facility to a nonprofit organization interested in installing their own system, city planners attending a WMU conference, and other local groups. "We discuss what it would take to do these sorts of installations, show them what it looks like, and talk about the footprints and the energy," says Bazuin.
"We're also in the process of training all of our tour guides in the College of Engineering and Applied Sciences because we regularly have open houses and do tours for parents and potential incoming students. When they walk through the building, we want to make sure they highlight the right things."
From here on out, Consumers Energy will inspect the solar garden twice a year, just to ensure everything is working properly. The company also has a SCADA system to monitor production values. "If there's a sudden drop, we'll check out certain pieces of equipment to fix them and get back up and running as soon as possible," says Warners.
A Grantek SCADA system is used to harvest points from the SMA cluster controller and an OSI Pi system is used to monitor the site.
To date, the facility is performing above projections, and people who are invested will continue to see that reflected on their bills. This summer during peak production, a person who paid $10 for one block saw a $7.00 credit back on their bill.
"If you're a customer," says Warners, "you can go to consumersenergy.com/solargardens, plug in your bill, and it will tell you how many blocks you should get if you want to subscribe to your entire energy usage."
Consumers Energy is hoping for more subscriptions over time to allow them to continue building. "We're authorized for up to 10 megawatts, and as we get more and more subscriptions, we'll look for a third site," says Warners. "Six more megawatts would power about 2,000 homes. Right now we're powering 200 and 600 homes—a total of 800 homes with our current four megawatts."
For those who are considering subscribing to offset their carbon footprint, they might want to consider this fact. "A subscription of one block is the equivalent to planting 12 acres of trees," says Warners.
Bazuin is also excited about what this means for future students. "Students like having that ability to know about energy-related power generation and have more access to seeing these things. We're also getting interest from some local high schools. I've heard from our advising and outreach people who say there are some local high schools that would like to come by and make sure the solar garden was part of their tour. The advantage is now we can walk them into our educational solar garden, and show them the components safely under supervision, while pointing at similar elements in the Consumers Energy solar garden next door."
And to think, this all started with average customers requesting to invest in solar and see their carbon footprint reduced.