Until recently, “solar roofs” was a term that applied primarily to private residences or small commercial buildings. But things are changing, partly because it is getting harder to find places to erect solar farms due to “not in my backyard” concerns and partly because people are slowly beginning to recognize that the best way to put solar power to work it to make it as close as possible to where it will be used.
The notion of distributed renewables is just starting to gain currency at the highest levels. Yes, it is cheaper to build huge solar farms on enormous tracts of open land, but then there are the costs of connecting those solar farms to the grid and distributing it to where it is needed. When you run all the numbers, there can be significant economic advantages to producing solar power close to where it will be consumed.
France Requires Solar Roofs On Car Parks
Last week, as part of the scramble going on all across Europe to replace cheap natural gas supplies from Russia with renewable energy, the French Senate approved new legislation that requires all car parks with space for more than 80 cars to cover those spaces with solar roofs. This has the rather splendid, if accidental, effect of making cheap renewable electricity available to any electric cars parked below.
But here’s the kicker. When complete, it is estimated all those solar roofs will provide an estimate 11 MW of electricity — equivalent to the output of 10 conventional nuclear power plants. Parking lot owners will have 5 years to comply starting from July 1, 2023. Lots with more than 400 spaces will need to comply within three years. Failure to comply in time will result in a fine of 50 euros per parking spot per month. For a parking lot with 80 spaces, the fine could amount to 48,000 euros per year. “We must not delay the implementation of the decarbonization of our economy,” Senator Agnès Pannier-Runacher said during the Senate debate on the legislation, Forbes reports.
Parking lots that have architectural, environmental, heritage, or other proven restraints, and car parks that have at least half of the property shaded by trees may be exempt. Parking lots for heavy goods vehicles weighing over 7.5 metric tons may not be required to install the solar panels and solar panel installation that “cannot be met under economically acceptable conditions” could also be exempt, according to Engadget. The legislation specifies that larger car parks must have at least half of the property covered in solar panels.
EcoWatch adds that many car parks in France are already equipped with solar panels, including the ongoing development of a 17 megawatt installation that will cover over 11,200 parking spots for Disneyland Paris. The new legislation is aimed at large car parks, especially near highways and major routes. In addition to providing renewable energy, the solar panels can also help shade cars from the sun, keeping them cooler. The French government has also launched a communication campaign called “Every gesture counts,” which encourages individuals and industry to cut their energy usage.
Solar Roofs In America Could Add 84.4 TWh Of Renewable Energy
A study by Frontier Group and Environment America finds the flat, open, sunny roofs of giant grocery stores, retail stores, and shopping malls are perfect locations for solar panels. The United States has more than 100,000 big box retail stores, supercenters, large grocery stores, and malls with almost 7.2 billion cumulative square feet of rooftop space.
The rooftops of America’s big box stores and shopping centers have the potential to generate 84.4 terawatt-hours (TWh) of solar electricity each year, equivalent to the amount of electricity that would power almost 8 million average US homes. Putting solar panels on the nation’s superstores would be good for electricity customers, good for the grid, and good for the environment.
Generating the full 84.4 TWh of clean solar power potential from America’s superstores would reduce global warming pollution by more than 52 million metric tons of CO2 annually — equivalent to taking over 11.3 million passenger vehicles off the road. Big box stores and shopping centers could replace half of their annual electricity use by fully building out their rooftop solar potential.
Producing electricity on rooftops, close to where the electricity will be used, reduces energy losses that happen during electricity transmission and distribution — losses that made up 6% of gross electricity generation in 2020. Solar power also makes the grid more resilient to outages and disruptions.
And that’s just the half of it. Think of all those parking lots at those shopping locations that could be covered with solar panels. What if the new law in France were applied in America? According to CNN, more than 90% of IKEA stores in America have rooftop solar systems. Why aren’t more large retailers doing this?
CNN asked that question of Walmart, Target, Home Depot, Kroger, and CostCo. Of that group, only Craig D’Arcy, director of energy management at Home Depot, agreed to talk specifics. His company has 75 solar roofs out of approximately 2,300 stores. He said aging roofs that may not be able to support the weight of a solar array were the biggest barrier. If a roof will need to be replaced in the next 10 to 15 years, it doesn’t make financial sense to add solar systems now, he said.
Johanna Neumann, senior director for Environment America’s campaign for 100% Renewable, told CNN, “Every rooftop in America that isn’t producing solar energy is a rooftop wasted as we work to break our dependence on fossil fuels and the geopolitical conflicts that come with them. Now is the time to lean into local renewable energy production, and there’s no better place than the roofs of America’s big-box superstores.”
“My suspicion is that they want an even stronger business case for deviating from business-as-usual,” Neumann added. “Historically, all those roofs have done is cover their stores, and rethinking how [they] use their buildings and thinking of them as energy generators, not just protection from rain, requires a small change in their business model.”
Perhaps the new incentives baked into the Inflation Reduction Act will help change some minds at these big box stores. There are benefits galore available for those who wish to take advantage of them. The time is right; the need is great. Let’s go, America. We can do this.
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