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Been thinking about this a lot recently, I guess the hurdle to clear is probably convincing Walmart to let you put solar panels over their parking lot. I wonder what the economics of it would be if Walmart did it themselves?

Tangential, the reason that we have so much parking space (as the article mentions) is that it is dictated by law in most places how many spots are required based on the building size. https://www.strongtowns.org/parking

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Walmart seemingly let SolarCity put panels on top of 240 of its buildings, then they started catching fire.

https://www.greentechmedia.com/articles/read/walmart-settlem...

AFAIK this is a Solar City problem, not a solar panel problem. It's too bad that the opportunity to do this was squandered thanks to quality/installation issues.

Shopping centre owners in Australia have been completing lots of solar canopy projects lately. The incentive is to power their shopping centre and save on electricity. It makes sense here because electricity is pretty expensive, so you get ROI really quickly. You also get paid for any excess generation you put back into the grid.

Not sure if this applies to commercial buildings as well, but for homes, you get paid a pittance for feed-in tariffs. It used to be lucrative and early residential adopters got great rates locked in presumably for life but anyone since faces tariffs that get reduced and reduced.

One hassle for those with the early tariffs is that they can't scale up their systems without revising the contract and losing their rates. Many early adopters were putting on 1-3kW systems (probably because panels were more expensive or they were not completely confident about the technology) when you'd probably put on 5-10kW now.

> Tangential, the reason that we have so much parking space (as the article mentions) is that it is dictated by law in most places how many spots are required based on the building size.

Why do you call that amount of parking "so much"? In general, places that only meet the legal minimum are a nightmare to park at because there aren't enough spaces in practice.

Net-energy metering is such a bad deal in most places that it wouldn’t make economic sense to do it.

Do many places actually do net metering? Where I live, feed-in tariffs are 1/4 or less of the electricity supply cost. Net metering isn’t sustainable if you amortise the infrastructure cost over the energy supplied. Even so we’ve seen the static connection fee portion of our bill rise much faster than supply costs.

Here in New Mexico, the power company has offered two choices for grid-tied solar. (1) "credits" for surplus power production. The return per kWh is much less than the cost to buy a kWh, but for some people, that's better. (2) no payment for surplus power production, but they "bank" it and you get an energy credit to be deployed when you need extra power.

The main distinction between which of these two systems is better is whether you have a seasonal variation that toggles between over- and under-production. If you do not need (much) heat, or if you heat your home with something other than electricity, and your PV installation is appropriately sized, you will likely not have an under-production season, and then cash credits, even if they are below market rate, are the most desirable. If you heat your home with electricity, even with contemporary air-source heat pumps, you will likely have some under-production during heating season, and then the energy credits are a better deal (1 kWh out for every 1 kWh in).

My home is in the second category. We produce 3x more than we need in summer, and only 1/3rd of what we need in winter.

Actually parking is dictated by the number of people they expect during peak shopping seasons.

They don't want to lose a single shopper because they make most of their money on those days.

If people couldn't park they would go elsewhere and that would be the end of that business.

Strong towns has a very myopic view on the world and they should not be used as a source.

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