Hitting on all cylinders

New agrivoltaics farm, set for completion in September, can power 300 homes

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Jack’s Solar Garden at sunrise
Byron Kominek

“But aren’t all farms solar?,” Lynne Wesenberg asked herself as she and her husband, Dave Dell, drove by a sign for a solar farm on North 95th Street one day. It’s a route they often take, having lived in Niwot for decades. Then they saw an ad in the Left Hand Valley Courier about Jack’s Solar Garden, the 24-acre plot of land they often drive by that is being turned into a community solar project. Wesenberg and Dell became the project’s first subscribers, paying a one-time subscription fee in exchange for discounts on their monthly Xcel bill for the next 10 years. 

“It just seemed like a good thing to do,” Dell says. 

“For the environment,” Wesenberg adds. 

Community solar is an emerging industry across the nation — a way for renters or homeowners without suitable rooftops or means to install their own panels to engage with renewable energy. (Reports from the National Renewable Energy Lab (NREL) in Golden estimate that only 22%-27% of residential rooftops can host solar panels.) The idea is simple: a solar array is built near existing infrastructure and renewable energy is fed into the utility grid, replacing fossil fuels and paid for by voluntary subscribers who in turn receive solar credits. 

Dave Dell and Lynne Wesenberg

In 2010, Colorado became the first state in the nation to pass shared renewables legislation, which was expanded again in 2019 to allow for larger projects. And although there are dozens of community solar projects around the state, Jack’s is a bit different, owner Byron Kominek says. Named after Kominek’s grandfather, who purchased the property in 1972, Jack’s will be home to 3,200 solar panels producing approximately 1.2 megawatts of power — enough to power 300 Boulder County homes. But it will also have community supported agriculture (CSA), an expansive pollinator habitat and a rigorous research component in partnership with Colorado State University, the University of Arizona and NREL, all open to school and community educational tours. 

“We are focused on making this not only a site that’s going to provide clean electricity and food for the surrounding community, but it’s also a really excellent learning opportunity and a research opportunity,” say Jordan Macknick, lead energy-water-land analyst at NREL. He’s been working with Kominek for the past two years to get Jack’s up and running and will be leading the research at the site. 

In a study published in the September 2019 issue of Nature Sustainability, Macknick and his colleagues from the universities of Arizona and Maryland explored the benefits of “agrivoltaics,” planting agricultural crops underneath and around solar photovoltaic (PV) infrastructure. They found that when solar arrays are set atop gravel and sand landscapes, it can easily create a “heat island” effect, making the area substantially hotter than it would be otherwise, while also decreasing the productivity of the panels, as they are known to be sensitive to temperature increases. According to an NREL press release about the study, “The co-location of PV and agriculture could offer win-win outcomes across many sectors, increasing crop production, reducing water loss, and improving the efficiency of PV arrays. Adopting such synergistic paths forward can help build resilient food-production and energy-generation systems.” 

NREL began researching agrivoltaics about 10 years ago, Macknick says, and now has 25 sites across the country. Some involve native vegetation, others pollinator habitat, pasture grass to support grazing livestock or horticulture crops, but Jack’s is unique in that it will encompass all four types of vegetation at a single site. Additionally, there will be a combination of 6-foot and 8-foot solar panels so researchers can study which height is most efficient. The panels will be on a single-tracking system that will start each morning facing east, follow the sun throughout the day and end facing west, and they will have a uniquely designed gutter system to help direct water to specific locations. 

Macknick says that at the project site in Arizona, researchers saw a temperature difference of 9 degrees Celsius under solar panels that had rock and sand ground cover versus those that had vegetation. 

“And that led to a 2% greater output during the summer months for that facility, which 2% sounds small but it ends up being a lot if you’ve got a big system like this,” he says. “I don’t think it’ll be as extreme here obviously as it is in Arizona. But we’re expecting to see measurable increases based on the temperature of the panels.”

From left: Byron Kominek, owner of Jack’s Solar Garden; Jonathan Koehn, City of Boulder chief sustainability and resilience officer; Jordan Macknick, lead energy-water-land analyst at NREL; Jon Wedel, senior director of commercial services at Namaste Solar; and Elise Jones, Boulder County Commissioner.

Increased efficiency is part of what drew Namasté Solar, which is constructing the solar array, to the project, says Jon Wedel, co-owner and senior director of commercial services for the company. 

“Our mission statement is to propagate the responsible use of solar energy. [Jack’s] is above and beyond anything we’ve seen so far,” he says. “On the back end, we’re always concerned about production and making sure that the system is producing and the ramifications of what’s happening here is really just exciting.”

Jack’s has drawn the attention of other community partners as well. Sprouts City Farms will be managing the CSA, and Audubon of the Rockies has already donated 3,000 perennials, including trees, wildflowers, currants, blackberries, elderberries and raspberries, for the pollinator habitat. Plus, Boulder County has signed on as an anchor tenant, sponsoring about 10% of the grid, or 327 panels, and the City of Boulder is currently in negotiations to sponsor 140 more. 

“I really see potential over the next couple of years in terms of what we learn, how that could be applied to existing projects, how we can start linking the idea of solar and food production, how we start thinking about increasing the health of our local soils and supporting local farmers,” Jonathan Koehn, chief sustainability and resilience officer with the City of Boulder, says. “So it really is such a comprehensive win that fits so nicely with our vision as a City and as a County.”

There’s also an equity component to the project: Jack’s is donating 2% of its energy production to low-income households in Boulder County and 30% of the CSA produce will be donated to the community. 

Angela K. Evans Byron Kominek, owner of Jack’s Solar Garden

Kominek is still looking for a researcher to assist on studying bees at the site, as well as a farm manager with Sprout City Farms to handle the CSA. And he needs more subscribers. Starting at a minimum of four panels, subscriptions are one-time payments and based on energy needs of a household, lasting for five, 10 or 20 years. But with construction currently underway, the solar array is expected to be completed by September. And once it’s up and running, there’s lots of anticipation about how Jack’s will inform future projects in Boulder County and beyond.

“We’re all waiting to see the results of how best to do this,” County Commissioner Elise Jones says. “It’s just hitting on all cylinders on the major values that we have around this, and so the County was really happy to dive in and try to help get liftoff off for this. And we hope to learn so much from it as we work to protect our farmers and support them. Solar farms could be an opportunity to add to their portfolio as we look to transition to clean energy.”