[Schroedingersat]

The business or land owner doesn't have to pay for it. Just let whoever put the panels up provided they provide x watts to charge cars. Even extremely cheap land is starting to show up as a significant portion of a solar install.

Store owner wins because covered parking. Panel owner wins because the increased logistics are offset by free land.

[gwd]

> The business or land owner doesn't have to pay for it. Just let whoever put the panels up provided they provide x watts to charge cars.

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."

[l1tany11]

I think it’s just way more expensive than you’d want. The schools here in California do it, and the steel superstructure is huge. Having done some steel moment frames for housing—let’s just say the cost isn’t in the panels. The moment arm for wind loads etc is not in your favor. My guess is you’re paying the cost of >10-20 panels to get 1 installed. Let’s call it a 15x cost multiplier. Even rooftop solar, which has a way worse multiplier (~4x) than power stations (2x?) can be hard to justify for some. You’re much better off covering the roof of the Walmart in panels than the parking lot. Which is why that is the case.

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.

[galaxyLogic]

> no one seems to have figured how to do it economically

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.

[MadcapJake]

There is a company working towards this that I believe has been mentioned here on HN before: https://www.legends.solar/get-early-access?grsf=texm9h (Feel free to lop off my referral code).

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

[Schroedingersat]

Probably a combination of insane zoning and tax laws that would make owning a parking lot that does something productive cost 10x as much as it yields and that landlords are as a rule stupid, petty, and greedy and demand a large enough share and dealing with them is so volatile that noone wants to take the risk.

[galaxyLogic]

Exactly. We need better laws

[galaxyLogic]

> why isn't this already a thing?

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.

[spockz]

And car owners benefit in summer from cooler cars due to the shade.

[Fomite]

Makes the lots much more difficult to plow in the winter though. Not relevant for large swathes of the world, but a problem in a lot of places.

[galaxyLogic]

I don't think you need to plow if you have roof over you.

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.

[Fomite]

I live in a place where snow doesn't stay where it falls thanks to drifting.

[ncmncm]

Actually not.

[bamboozled]

Everyone benefits from this

[cassepipe]

No. If the solution is to price in the externalities, it only makes sense for Walmart to pay for it. Their parking means less land with vegetation that can capture carbon and all the bad externalities that comes with land artificialization. Plus, they will probably benefit from it because else what are peope going to do when they come back in a car that unbearably hot (and extreme heat events, and extreme cold events for that matter, are going to more more frequent ) ? Leave the engine on for condtionned ? That would be crazy.

[ncmncm]

My local Walmart has solar over much of its parking lot. All the cars huddle under it.

Meanwhile, the store roof entirely lacks solar.

Nearby Safeway is opposite.

[galaxyLogic]

Good starts. Must start somewhere. We all want an electric car and a lack of charging stations is a problem. Therefore I would vote for starting with parking lots, they are closer to cars.

[ncmncm]

Big-box store roofs are much cheaper to install on than building elevated racks in parking lots. Electric power is easily delivered where it is most useful via wires. So, for cost-effectiveness, the first place to put solar is on those big flat roofs. But customers do like covered parking lots.

[Schroedingersat]

> No. If the solution is to price in the externalities...

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.

[galaxyLogic]

It's not only companies providing parking lots for their customers. In big cities it is big business to provide parking for whoever needs it. Railroads need parking lots for their customers who drive to the station with their cars and park them there.

[galaxyLogic]

And the car-owner would win because their parking would be cheaper