Solar PV paving

[Ludus]

There's a French company that got a government contract to pave 1000 km of road with PV.
Wattway by Colas | Paving the way to tomorrow’s energy

This is a serious company with decades of experience in road building.

This seems like a much more serious project and technology than the US couple who raised a lot on indiegogo for solar roads.

It's glued directly to existing good paving and painted with some sort of transparent coating.

They seem to be trying to use it in the same difficult case of roads. I'd think there would be an enormous market with just gently used paving like paved shoulders, service drives, outer parking lots or driveways in warm sunny climates. I suspect just those areas would be many times the current total installed solar PV.

Comments?

 

[Tempus]

same as with the other one - this really seems to be a case of solving a problem that doesn't exist... it's not like we've run out of places to put solar panels that DON'T get driven on...

 

[gimmi80]

Interesting project but Their logo looks to me like a huge middle finger...

 

[tomas]

I think it is awesome. Municipalities can go net zero energy consumption as they update roads without using new land or major construction. What's wrong with that? I'd buy the bond.

 

[BluestarE3]

Durability? Cost of repairs? Impact of dirt and grime?

 

[tomas]

Agree those are potential issues, and I'm sure company is aware. Nobody gets as far as they have without an approach for the obvious challenges. One of two things will happen: they will overcome the challenges, or the technology will fail. But let's try!

 

[BluestarE3]

Just seems to make more sense to put PV alongside the roadway (parallel with and using the existing right of way) than onto the road surface itself.

 

[dhrivnak]

How about parking lots? The land is already allocated.

 

[rypalmer]

Solar roads and solar parking lots are both terrible, terrible ideas.

 

[Ludus]

Solar roads and solar parking lots are both terrible, terrible ideas.

This is a critique of a very different project. None of these arguments apply.

This couple had no background and no credentials. Colas is a company with many decades of experience building roads and there's serious R&D in the solar panels.

Unlike the project critiqued, the Colas paving is glued to existing good pavement and coated in a transparent sealant. The project critiqued is wildly more expensive and impractical and only applies to completely rebuilt roadways or surfaces.

 

[Ludus]

How about parking lots? The land is already allocated.

Parking lots, driveways, service drives seem like the main application to me.

 

[Ludus]

same as with the other one - this really seems to be a case of solving a problem that doesn't exist... it's not like we've run out of places to put solar panels that DON'T get driven on...

Except in a lot of specific situations we have run out and the real use case is always specific.

Walmart stores cover all the available roof space with PV panels but are surrounded by several times that much area in parking lot. It really doesn't matter if there is other rooftop space a mile away available that belongs to somebody else who's not interested. "We" don't have space to put solar panels, specific users do or don't. Paved areas may greatly increase their options.

The potential advantage if this works at all is that it could be MUCH more automated and systematic than rooftop installation. Most of the cost of rooftop solar is not the panels it's all the fuss fitting them to unique situations. Every rooftop is different and poses code and technical issues. Paving is not like rooftops. There aren't a thousand special cases.

Consider Tesla's factory in Fremont or Elon Musk's house in Bel Air. Why not solar panels? The factory could take some but look at the roof in Google Earth. It's a very complicated collection of a lot of different roof types. Lots of roof fixtures. It would be a complex labor and planning intensive job and consequently quite expensive for the power output. By comparison consider the parking lots and service drives. Covering little used areas would be much simpler. Elons house is a French style mansion without much suitable roof space. Some panels could be placed (and look pretty ugly) but not enough to make a dent in the house's demand. OTOH there's a full size tennis court and a large drive. If they were covered with PV panels the output would be enough to make the house net zero. It's an odd case but the world is a collection of odd cases. If solar panels could cover pavement it would let Elon Musk's house go solar. Rooftop won't. In that case it solves a problem. Are there other Cali mansions like it? Thousands.

In large areas of the US, there's more area devoted to unoccupied pavement than rooftops. More importantly, if it worked, this sort of thin solar panel overlay would be a lot simpler and easier to install than rooftop panels and might have lower total costs.

 

[rypalmer]

Too bad people actually park on parking lots though. Solar canopies, though...

 

[BluestarE3]

Too bad people actually park on parking lots though. Solar canopies, though...

Exactly. Canopies provide the additional benefit of covered parking spaces, which saves energy by reducing the need to run the AC at max when returning to your your car after it has spent hours sitting in the sun while you shopped or worked at the office. What's the cost/benefit difference between installing PV canopies that can generate electricity all day vs. installing PV pavement that can only generate electricity when no cars are parked over the space?

 

[Ludus]

Very true and although they would likely be more costly and need more customizing to the space, they're a good solution.

Most parking lots though have a lot of surface that almost never is shadowed. Driving lanes rather than parking slots and parking slots in the outer fringes. Companies that do regular satellite photos could provide data confirming it but most lot owners could easily tell just which parking slots are almost never used.

To me the cool thing about this is how enormous an area is represented by the easy cases. Most of the easy cases would be easier and cheaper than rooftop or canopies.

Consider just tennis courts. They're usually just sitting there in the sun. No vehicle use. Not much stress on the surface. There are thousands of them.

 

[Ludus]

Consider the Tesla Gigafactory. It's designed for full rooftop solar PV so the usual issues with HVAC, loading, leaks etc are designed out.

It will be surrounded with parking lots and paved service drives and areas. Some of those would be well served by covering them with canopies.

I think these guys have a pretty elegant version. Home - PowerParasol
This creates large shaded sun dabbled spaces that can have greenery too.

Once you've got a couple thousand parking spaces covered by canopies you still have more.

Edge lots and excess parking could be covered in solar paving. So could service drives and other paved spaces. That would amount to acres of PV and megawatts of output in a project this size.

With Solar paving you could get pretty close to productively using all the sunlight that falls on the the built area of the plant. It's wouldn't be a competitor to rooftops or canopies, it would be an addition.

 

[aja2460]

I believe that I may visit Colas to talk about their project late in June. Putting solar panels along highways is a good thing to do, but it's not as easy as it looks. We're doing that as well
.

 

[dhanson865]

If it uses microinverters or optimizers so that shading isn't an issue and I could get it cheaper than traditional PV for my roof I'd have no problem with covering my driveway and part of my front yard with it (I'd get rid of some grass/weeds and turn that into paved area).

But it would have to be very cheap. Shading isn't much of an issue on my roof but it very much is so for my driveway.

If I get 1 hour or less of shading a day on my roof I probably get 4 hours a day or more of shading on some part of my driveway (house, trees, telephone pole, chain link fence).

 

[SageBrush]

Will they be tearing up the PV every time they repave the road ?

At a minimum it sounds like they need sparsely traveled roads that can last 30 years after the PV refurb.

 

[deonb]

Consider just tennis courts. They're usually just sitting there in the sun. No vehicle use. Not much stress on the surface.

I'm always stressed when I'm on a Tennis court...