Store owner wins because covered parking. Panel owner wins because the increased logistics are offset by free land.
Snow covering the solar panels could be a problem. But perhaps even in winter there is a bit of sunlight which could produce electricity to warm up and melt the snow.
Which sort of begs the question, why isn't this already a thing? Why aren't there companies going to businesses which own parking lots and saying, "Let me lease the air above your parking lot. I'll install and maintain the frames and the solar panels, manage the connection to the grid, the whole lot; I'll pay you $x per meter per month, and your customers have shade."
Yeah it’s a better use of land, it keeps the cars shaded, but no one seems to have figured how to do it economically. Even in Southern California where it’s very sunny, and power is very expensive. I just don’t think it’s anywhere close to being economical. And in other markets the economics are almost certainly worse.
Mass-production is the key to economies of scale. Government policies can play a huge role in steering us towards goals like that.
Why is America so rich? Because of car-industry. And why is car-industry so prominent? Because of the interstate highway system.
Perhaps the Inflation Reduction Act subsidies will, or should, make it a thing.
Government subsidies (incentives) is a good thing if it can save the planet and prevent the devastating floods and forest-fires and drought that is killing us now.
I'd argue that this is likely more challenging than it seems, with city/state/county building codes, plus just building on existing dense spaces, and add to that any grid/utility policies and associated costs to play ball
Meanwhile, the store roof entirely lacks solar.
Nearby Safeway is opposite.
I mean I'd love pricing in the externalities, but then it'd be moot because there'd be a building rather than a parking lot, no walmart, and a train or bicycle rather than a car. There'd also be plenty of roof area for solar panels in any place with a density lower than tokyo metropolis so you wouldn't even need to build supports.
Say goodbye to all rural farmers markets.