Benefits of Solar Parking Drivers and the Environment. Why Aren’t There More of Them?

Commuter students and tailgaters at Michigan State University get a little relief from the elements when they park their cars to go to class or a football game. Solar panels, tall enough to park an RV underneath, stand on steel trusses over the lot, providing a bit of shelter and shade. Not only can the university cheap, clean solar energyits students have cooler cars in August and don’t have to spend time scraping their snow-free cars in 20-degree weather in January.

I know because I parked under them for almost two years as a commuting student.

I wonder what a useful system it seems strange that every parking lot doesn’t have solar panels on it. Each installation of solar panels has a different calculus, if this on a roof, on earth or above the parking lot. Owners of large parking lots may not install solar there for a number of reasons, including cost and inconvenience. However, some solar experts think it’s possible that growing interest in sustainability could lead to more solar parking arrays in the coming years.

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The upfront cost of solar

For many homeowners, installing solar panels can save them money in the long run. The same is true for large institutions.

Michigan State estimates that the parking lot panels (located over five lots) could save $10 million over 25 years. The university gets electricity from panels under a power purchase agreement, which means that it does not own the panels but agrees to buy the power. It saves by getting power at a lower price than alternative sources.

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While the economics of a power purchase agreement are somewhat different, for the company that absorbs the construction costs, building elsewhere is a better deal.

“A carport is about 40% more expensive compared to a ground mount system,” said Tim Powers, a research and policy associate for Inovateus Solar, the company that built the system in Michigan State. It’s more expensive because of more materials (it requires taller, stronger structures to get solar panels farther from the ground), more labor (it requires a longer build) and more engineering costs, he said.

If the only motivation is to get solar for the cheapest possible price, carports are not the way to go. But there are other reasons that an institution may adopt solar in their parking lots.

Michigan State’s carports have won national and state awards, and account for 5% of campus energy consumption – a step toward the university’s sustainability goals and a welcome round of good publicity. Many people I interviewed for this story suggested that it might make the university more attractive to prospective students, although empirical evidence of the impact of staying at a school on a student’s choice is more limited. hard to find.

Recent research suggests that while 65% of consumers (not necessarily students) say they are interested in buying sustainable or green products, only 26% actually do so. While shopping habits and choosing a college seem like apples and oranges, carport solar panels and green consumerism can be the perfect match where you get your literal apples and oranges.

The rise of electric cars

The threat of climate change requires a rapid reduction in greenhouse gas emissions. While many problems require systemic solutions, individuals are adopting green technology, such as rooftop solar panels and electric cars, at rapid rates. On top of the green benefits, both solar panels and electric vehicles likely to save money over time. It is possible that stores with multiple parking lots can economically exploit both.

For example, a solar carport covering an average Walmart parking lot has a capacity of about 3.1 megawatts, said Joshua Pearce, a professor of electrical and computer engineering at Western University in London, Ontario.

Pearce modeled the viability of solar carports at big box stores, singling out Walmart for its ubiquity. The chain also makes public sustainability commitments and is one of the leading corporations in solar capacity installed. Walmart says it has 600 onsite renewable energy installations, but did not share information about planned or installed parking lot solar canopies. It has reportedly installed at least seven across California.

While it’s hard to say if someone will opt for one retailer over another because of the environmental messaging of a large, visible solar array, will they if it means parking from the sun, snow or rain?

Pearce has a hunch that they might, although his research doesn’t look at this question directly. He believes stores can attract more customers by offering discounts or free electric car payments to shoppers.

The average Walmart parking lot can support about 100 electric vehicle chargers if covered with solar panels, Pearce’s research found.

“I believe that if you are given free parking under a canopy that can charge your electric vehicle, you will spend a lot of time in the store because you will be waiting to be charged,” he said. “Even if you buy one thing, that will be a net profit for the store.”

Pearce is looking to investigate this hunch in the near future by seeing what happens when the charge is actually given. Are nonelectric vehicles parked there? Are people taking a long time in the store?

In the future with free electric charging at Walmart (or another big box store), shoppers can go home not only with their shopping haul but with more of a charge on their car than when they left. According to a study by Pearce and a colleague, 90% of Americans live within 15 miles of a Walmart, and a one-hour shopping trip can give a car a 20-mile charge.

“This means that for many shoppers with an EV, the trip to Walmart and back may have zero car-related energy costs,” the researchers wrote.

While a world where stores charge electric vehicles to their customers for free and make a lot of money in the process sounds great, it’s still hypothetical at this point.

There are hurdles to overcome, especially when retrofitting an existing parking lot with a solar canopy. This includes closing parts of the parking lot while construction takes place, which could make a store a more inconvenient option, at least for a time.

Pearce echoed what Powers from Inovateus said: Accounting only for installation costs, it now makes more sense to install a shop roof than a solar farm on open land.

“But then, if I don’t want to take up more land, maybe I’m forced to land for some reason, then the parking lot is the way to go,” Pearce said.

Potential change on the horizon

“We see turning carports into parking lots as a great dual-use story,” said Tyler Kanczuzewski, vice president of sustainability at Inovateus. Dual-use refers to the practice of using land for two things, for example, solar power and growing crops.

According to a study published in Nature, large solar in the US is mostly located outside of cities. Fifty one percent of it is placed in deserts, 33% in farmland and 2.5% in urban areas.

Land use decisions are always fraught. Installing solar in deserts raises cultural and ecological concerns. Rural solar farms have sparked debates. The Michigan State installation retains 45 hectares of agricultural land in production, a fact that Michigan State called to promote one of the many awards it won for the array.

Parking lots, on the other hand, are mostly good for one thing – parking – and solar canopies can enhance that experience.

Will increasing interest in sustainability make solar parking lots more common in the future?

“The project was difficult,” Kanczuzewski said. While they are more common in the Southwest, installing solar on top of parking lots is less common in the Midwest where Inovateus does most of its business. By solar capacity, 95% of Inovateus’ installations are ground-mounted utility projects. Of the number of projects, 65% are ground-mounted, 30% are rooftop and about 5% (only three projects in total) are above parking lots.

“They’re not a common choice,” Powers said.

It may be a more sustainable one, though.

“I think it’s super sustainable,” Kanczuzewski said. “Instead of acquiring new land or additional property, why not take an existing lot and go solar?”