EEVblog #632 - Solar Roadways Are BULLSHIT!

[ErikTheNorwegian]

https://www.theguardian.com/environment/2016/dec/22/solar-panel-road-tourouvre-au-perche-normandy

[f4eru]

>>
They say theat they embedd glass fragments in the covering (probably resin). Not sure if it's done in series prod.

[Brumby]

Why is there no longer a video feed?  Because the generation 3.1 panels are being installed right outside Solar Roadways' front door  ... which faces North incidentally.

That would be a good thing in Sydney ... but, then, we are on the other side of the equator.

[Brumby]

"Can Streets Become Giant Solar Panels?"  That is almost funny... of course they can.

All sorts of pain and suffering come from asking the wrong questions.  The answers are irrelevant, insignificant or misleading, no matter how great they are.

The better question is Should they?

[f4eru]

That would be a good thing in Sydney ... but, then, we are on the other side of the equator.

Even in Sydney, and on a scale, it will be 3-10 times more expensive than ground-based solar panels. And I think in Australia there is more than enough available ground space.

Also the location they have used is not good, they put them in Normandy, one of the cloudiest part of France.

Now I imagine the nightmare this will be for maintenance, but it will show in the next months. My guess : in a few months, they will be 5% of unusable/disabled segments.
Also, a damaged segment probably has to be removed quickly, because if the panel is ripped, and the live wiring is visible, people might try to grab it, and the electrocution risk is big.
Typically accidents can damage a few mm of the black top of the road, when metal touches the road.

And how do you remove a glued in place panel ?
My guess : they don't have provisions for removing, and the road will have some segments closed due to electrocution risk.

[tszaboo]

they need to convert 1 million km of road to solar, and then the country would be totally solar powered. Anyone wondering, that is only 5 000 000 000 000 EUR, or the total government budget for 4 years.

No-one in their right mind would think this means they will rip up 1mKm of road and lay solar panels as one job. The obvious way to do it is to fit the panels as roads would normally be repaired, so a) it's an ongoing job over a long time, and b) costs not so much since you're saving on not paying to fix the old road anyway.

No-one in their right mind would think that solar roadway is the solution.
The money can be used to make 10 times as much power, if you put the panels just next to the road.

[PlainName]

No-one in their right mind would think that solar roadway is the solution.

To what?

But if you read my post again you'll see that I wasn't arguing for or against the panels. I was pointing out that the argument against them - that they will cost the price of the Universe plus tax to fit en bloc - is invalid. Sure, say they will be more expensive, but going off on serious over-exaggeration just makes whatever good points were there invisible.

if you put the panels just next to the road

Where? It's not going to happen because they would be fugly to start with, prevent normal road furniture  being used, possibly be a safety hazard (restricted vision) and kill off the nice grass vergers, etc.

[Barny]

Where? It's not going to happen because they would be fugly to start with, prevent normal road furniture  being used, possibly be a safety hazard (restricted vision) and kill off the nice grass vergers, etc.

How about: On top of the Houses?

Or: Above the Streets to shade the streets?
No more problems with deep sun or heavy rain.

[iaeen]

No-one in their right mind would think that solar roadway is the solution.

To what?

But if you read my post again you'll see that I wasn't arguing for or against the panels. I was pointing out that the argument against them - that they will cost the price of the Universe plus tax to fit en bloc - is invalid. Sure, say they will be more expensive, but going off on serious over-exaggeration just makes whatever good points were there invisible.

if you put the panels just next to the road

Where? It's not going to happen because they would be fugly to start with, prevent normal road furniture  being used, possibly be a safety hazard (restricted vision) and kill off the nice grass vergers, etc.

That argument is not invalid.

The first question to ask is how often are (conventional) roads resurfaced. I'm not sure what the answer is here, but every 10 years is certainly a generous estimate. That would mean we need to replace approximately 10% of our roads in any given year. Since replacing 100% of the roads would cost 400% of the national budget, if we set out to replace all newly repaired roads with solar roads, it would cost 40% of the national budget every year for 10 years just to get a country converted. That is not realistic.

The next question that needs to be asked is how often do the new solar roads need to be replaced. I doubt these will last 10 years (I actually doubt that of conventional roads too... maybe the best concrete money can buy would get close to this, but cheap asphalt won't even make it 5 years without some form of work), so the cost is never going to go away. It will only go up.

[PlainName]

Above the Streets to shade the streets?

Yes, I'm sure the locals will enjoy the eyesores and no-one will complain about walking around in permanent gloom How high off the floor do they need to be, and how flimsy can you get away with the supports being? Where are you going to bang in the supports? Etc. Next to a road is a worse option than the road when you get down to the details.

On top of the Houses?

The ones that don't already have them, you mean? Any idea of the area of roof space vs road? Who is going to pay for the householder to  benefit (or compensate them)?

Come to that, why not have them on the roofs as well - can't have too much energy available

[PlainName]

The first question to ask is how often are (conventional) roads resurfaced. I'm not sure what the answer is here, but every 10 years is certainly a generous estimate.

I'm happy to go with that guestimate.

hat would mean ...

But you've lost me there. I think you are considering that we take road A and say "this is going to be a solar roadway" and then do it. That's the approach I think is wrong. Instead, you take this road, B, that is going to be repaired anway and plonk down the panels instead or repairing it the normal way. The cost is thus the cost of the panels less the cost it would have otherwise been to repair it. That may mean that road A doesn't get around to being done for 10 years, but meantime other roads will be being done.

In other words, this:

f we set out to replace all newly repaired roads with solar roads

is, sorry to be blunt, bonkers. You place the panels TO repair it, not afterwards! No wonder your costs would be so high

[SeanB]

To repair a road you need to either overlay a road bed in reasonable condition with new or recycled bitumen and gravel mix, or mill it out to the underlayer ( or at least the 50mm wear course), repair the cracks and sags in the underlay and then put a new wear layer on it. The majority of the cost is the milling out, or the new layer if building up and redoing all the kerbing and edges.

Solar roadway you still need to do this all, then add in the cost of putting in this expensive and likely fragile ( as in the road crews will pooch a lot in putting in 1km, so you probably will start with 2km to get 1km of semi working panel out afterwards) till installed panel in. Then you need to do kerbside works to place the inverters, cabling and such to channel this new power into the local grid. then what about the typical things that happen to a road bed, what will you do when a water pipe under the road bursts, or a sewer needs work, or when you need to dig a trench to repair a clogged storm water drain. these are things a tar road handles well, you just end up with a patch of new tar somewhat matching the existing bed profile, and things carry on. Solar roadway first you need to disconnect that section of grid, then isolate the relevant road bed segment and isolate it, then safely ( remember, this is a high voltage source that you are about to shove a metal shovel, either with somebody leaning on it or driving the mechanical digger) make your initial cut, then dig your trench ( and hope that you do not have to do the typical follow the line to find the actual leak/valve/non broken pipe), do the repair, fill the ditch and recompact it, then reinstate the underlay, repair the wear course and finally either leave that section safely isolated ( because you cut a long slit in the panels, and went through 2 or more segments as well) and waterproof the cut ends, or repair it again and reconnect.

Regular roadway, you get the cones out, the danger tape, the construction signs and the flags off the truck, put out, and a half hour later you are digging. fix the problem, put the pile of sand back, run the plate compactor over each layer, redo the underlay, slap some premix on top and compact it with the plate compactor and a roller, and an hour afterwards the road is clear for use.  Solar roadway, first get the company out that installed, they show up 2 days later, start to look for the mislaid plans, cut the wrong sections, repair and find the right sections, then finally a week later declare it ready for you. Then you can fix that water main, too bad for the people living in the area, who have had no water/power/gas/sewage/stormwater drainage/telephone/cable/road access for that week, plus they will have the same for a week afterwards while the company fixes the solar paneling or safes it.

Add to this solar panels are really only economical with a 25 year payback time, but a road surface will show wear after 5 years, and a 25 year old road bed is known here ( as so often happens with deferred maintenance or no maintenance) as a grass road, from the grass growing in the cracks. a retop every 10 years will keep it working, and here we do not have to deal with those annoying things like snow ( really bad for a road when you scrape it year on year with a bulldozer blade to move the ice layer, let alone corrosive salt) or anything aside from the nice 37C day that summer gives. Great for solar power generation, but not good when your panel is at 130C in the open sun with no chance for cooling, and not too good for the embedded inverter as well sitting there in the melting tar.

[iaeen]

The first question to ask is how often are (conventional) roads resurfaced. I'm not sure what the answer is here, but every 10 years is certainly a generous estimate.

I'm happy to go with that guestimate.

hat would mean ...

But you've lost me there. I think you are considering that we take road A and say "this is going to be a solar roadway" and then do it. That's the approach I think is wrong. Instead, you take this road, B, that is going to be repaired anway and plonk down the panels instead or repairing it the normal way. The cost is thus the cost of the panels less the cost it would have otherwise been to repair it. That may mean that road A doesn't get around to being done for 10 years, but meantime other roads will be being done.

In other words, this:

f we set out to replace all newly repaired roads with solar roads

is, sorry to be blunt, bonkers. You place the panels TO repair it, not afterwards! No wonder your costs would be so high

Sorry you're having trouble keeping up, but my post was addressing your exact scenario. I should have said "if we set out to replace all needing-repair roads with solar roads". That would have been more clear.

It doesn't matter whether you think about this as "repairing" or "replacing" the existing road. Solar roads still cost hundreds of times more than conventional roads + conventional solar panels to install. You can't magically make an astronomical cost manageable by spreading it out over time.

[tszaboo]

The first question to ask is how often are (conventional) roads resurfaced. I'm not sure what the answer is here, but every 10 years is certainly a generous estimate.

I'm happy to go with that guestimate.

hat would mean ...

But you've lost me there. I think you are considering that we take road A and say "this is going to be a solar roadway" and then do it. That's the approach I think is wrong. Instead, you take this road, B, that is going to be repaired anway and plonk down the panels instead or repairing it the normal way. The cost is thus the cost of the panels less the cost it would have otherwise been to repair it. That may mean that road A doesn't get around to being done for 10 years, but meantime other roads will be being done.

In other words, this:

f we set out to replace all newly repaired roads with solar roads

is, sorry to be blunt, bonkers. You place the panels TO repair it, not afterwards! No wonder your costs would be so high

The cost argument in bonkers. Putting solar panels next to the road, and repairing the road cost the fraction of the solar road. You need to repair the road every ten years, and the panel every 25 years.
They even managed to raise a good question in the video: They are not even sure, if the road will break even in energy. Meaning: over the lifetime of the road, they are not sure if it will make more energy, than it takes to make it. The entire concept is just bonkers.
Dont think that we fully run out of space. That is just bullshit. There are parking lots, which can be covered with panels. The entire railway network can be fitted with panels on the top. There are 30.000 KM length of railway network there, until it is fully covered by solar panels, the roadway is not economical.

The thing about solar power, people keep forgetting is simple. Everything is about the numbers, and money efficiency. If option A is better than option B, you should always do option A. Its not "a little bit of everything cannot hurt". Yes it does. It increases the price of energy, and wastes money.

[PlainName]

Solar roadway you still need to do this all

Yes, but you'd have paid that anyway. The panel installation is thus subsidised. Of course the panel are expensive (well, they're not free) - no-one is saying they are a no-cost option. Fragile? Well, we'll see - isn't that what these test roads is all about?

I am a bit flumoxed but the, well, I was going to say negative  but it's verging on the spiteful, vibes. Sure, the roadway may be really very crap, but for more than one municipal authority to bother laying a test road there has to be something someone with a clue has seen in it. If it doesn't come off it doesn't come off, and if it does y'all are going to look right plonkers. But it seems to me to be daft to be standing pointing fingers and shouting "It'll never work" at them when they will clearly find out pretty soon if it does in practice or not. Why not give 'em a chance to write up the experiment?

[f4eru]

But it seems to me to be daft to be standing pointing fingers and shouting "It'll never work" at them when they will clearly find out pretty soon if it does in practice or not. Why not give 'em a chance to write up the experiment?

We don't say "It'll never work".
We say : "It'll never be economical"

Huge difference !

[Delta]

It will always be several times more expensive (per W or Wh generated) than conventional solar PV.  For that reason alone (ignoring the myriad other reasons) it is an utterly stupid idea.

[PlainName]

Plainly, despite what you think, people with the clout and money may have a different view. unless you are privy to their spreadsheets and mindset I don't think you can be as robust as the views in this thread suggest. Sure, you can be doubtful, but whenever I see someone take the plunge like this I (nearly) always think "what am I missing" rather than increase the bet (or dig a deeper hole, as the case may be).

[PlainName]

It will always be several times more expensive

Like nuclear, then?

an utterly stupid idea

Ah, just like nuclear, then

[ataradov]

Well,  so far the problem is that people with money,  don't rush to spend their own money and extract taxpayers money instead.

[ataradov]

Ah, just like nuclear, then

Not at all. There was a clear path for nuclear energy.

Solar panel installed as part of the road surface will always be less efficient and more expensive. There is no way around this limitation.

[LabSpokane]

Ah, just like nuclear, then

Not at all. There was a clear path for nuclear energy.

This is about solar roads, not nuclear. We'll debate you into the ground about clean, safe, reliable, nuclear baseload power elsewhere.

[Brumby]

Plainly, despite what you think, people with the clout and money may have a different view. unless you are privy to their spreadsheets and mindset I don't think you can be as robust as the views in this thread suggest. Sure, you can be doubtful, but whenever I see someone take the plunge like this I (nearly) always think "what am I missing" rather than increase the bet (or dig a deeper hole, as the case may be).

You are being rather naive.  What you are "missing" is painfully common.

The people with the clout and the money are playing a political agenda.  They don't have a real grasp of the technology and economics and are being "sold" the idea by people who have put some ideas together which have attracted the interest of the media.  Since the media love to make things upbeat, green or whatever is selling - the public are drawn on board ... and whenever the public are involved, the politicians are going to play along.

Sorry to burst your bubble - but that's how the world really works.

The real crunch will come when billions have been spent and the return on investment has been clearly demonstrated to be a disaster.  At that time, it will be dropped like a hot potato ... but until then, those with vested interests, the greenies and the fan-boys will be singing the praises.

[rs20]

The real crunch will come when billions have been spent and the return on investment has been clearly demonstrated to be a disaster.  At that time, it will be dropped like a hot potato ... but until then, those with vested interests, the greenies and the fan-boys will be singing the praises.

Don't forget the part where all the fanboys and greenies (who were so sure it was a good idea) start conspiracy theories that "big oil" somehow sabotaged the project...

[Kean]

So, I don't recall if this has been discussed here or elsewhere, but I was thinking that one way the proponents of these solar roadway schemes could actually justify the apparently terrible ROI is that they are also factoring in the cost of the land needed for equivalent solar farms, versus an effectively zero cost for use of the roadway surface area.