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Comment by t1234s | Hacker News Reader

Solar panels == shade. Any companies deploying solar in this manner (parking lots, pedestrian trails, bus benches, etc..)

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Locally Michigan State is covering all their parking lots with solar panels. The added advantage is that since you're car is parked under them you don't have to clear the snow off.

https://ipf.msu.edu/about/news/solar-carport-initiative-earn...

But what I haven't figured out is if they have to broom them off after a snow or just wait until the sun melts it. By the time I am around in the afternoon time they are always cleared.

No idea if anyone actually does this. In theory, you could forward-bias the panels with an external power supply. That should generate infrared light at the band gap, which should melt the snow.

It might be enough to just form a thin layer of water, so the whole mass of snow slides off.

For panels in northern climates, if the tilt is fixed or just seasonally adjusted (i.e., not tracking the sun), we often will bias towards a bit more vertical tilt than mathematically optimal to encourage snow shedding.

Unless it's borderline melting, brooming is not enough, you'd have to move the snow away or berms would form quickly.

Panels have a low albedo - they absorb a lot of energy. About 25% of that is turned into electricity, the rest heats the panel. So as soon as a corner is exposed to the sun, it tends to melt off the rest of the snow comparatively quickly.

This gets proposed a lot. The reason it isn't more frequent is due to the cost of the structure to hold the panels & risks of people running into them.

It would be great if these costs could come down. Parking lots, animal pastures & other areas could be protected & create energy at the same time.

They also light on fire occasionally

Here is a large installation over surface parking at a VA medical center. I think it is just a matter of time before this becomes the standard everywhere.

Lat, Lon: 29.701864, -95.388646

https://maps.app.goo.gl/N7U4EmUVQsFG6gfZ8

I did a presentation on this in college back in 2008...the math was good even back then as far as electricity payback and other benefits.

And solar has gotten way cheaper since then. It's a no-brainer.

> risks of people running into them

Curious how people run into solar panels. I wonder how many ER visits say "I ran into a solar panel"

Drivers hit structures all the time.

and? Why is it a problem with solar panels?

More expensive and urgent to repair than a light pole.

People drive into buildings all the time. Like it's actually like over a hundred per day sort of thing in the US. Happens really frequently here in Canada as well.

If you include stuff like stop signs, light poles, mailboxes, and fences its probably in the several thousands. Fixed object collisions are super common.

Even animals (with significantly smaller brains) know how to avoid stationary structures (and even moving things that are trying to eat them!).

Where are ya'll from that people are running into stationary structures all the time? If people have an epidemic of running into stationary things, wouldn't there be a 100x problem of them running into moving things - like cars, trucks, trains, airplanes?

Regardless, why is it okay for people to run into any stationary structure but not okay for people to run into structures that hold solar panels? Or is there some effort to remove ALL stationary structures because of this problem?

Probably ya'll need to update the driver's license exam. First, in the written exam, include rules against hitting stationary structures, and quiz them on it before issuing the learner's permit. Then also test for it during the road test. If they can't avoid a stationary structure, perhaps fail them?

In the US, this is not a problem unless you are drunk. When you are driving drunk, you are violating the law anyway.

We don't know the state of the multiple drivers to cause these posts, or for the drivers to run into the corresponding posts, but they're a) in the US (Atlanta, Oakland, and Brookfield, CT) and b) it sounds like it's happened more than a few times.

https://old.reddit.com/r/cars/comments/myfroy/today_the_14th...

https://old.reddit.com/r/HomeImprovement/comments/5da1w1/bes...

https://i95rock.com/how-to-avoid-a-car-crash-as-you-approach...

> it's happened more than a few times.

There are 2.75 - 4 billion buildings on this planet. Something will happen a few times or more than few times. Sometimes asteroids hit the planet and most species go extinct.

If you put solar panels in parking lots, you're adding a lot of posts to the parking lot to hold them that weren't there before. People are going to crash into those posts in parking lots often.

For example, light posts constantly get bumped in parking lots.

To hold your solar panels you need really strong posts that can both hold them and get bumped into by vehicles. Especially in the USA where you have giant vehicles & tight parking spaces.

This all adds to the cost before you even get to electricity storage & transmission.

The other main obstacle to solar construction anywhere is grid permitting.

China is doing a lot with combining solar and fish farms.

Yes, many companies are doing this in their parking lots, even some govt buildings do this. My local library has panels setup over part of their parking lot for instance.

Is it economically viable (pays itself)? It looks simple, but designing a shade is no small feat.

I looked once into solar covers for EV charging spots and it would provide like 5% of energy, not worth the hassle.

For parking the convenience is definitely worth it, but economically I don't think supermarkets care that much.

I've never done the math, but I've seen Walmarts start putting solar panels as cover in their parking lots.

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