Author Topic: The road to solar...  (Read 2723 times)

quixoticgeek

  • Mostly Harmless
The road to solar...
« on: 27 July, 2021, 09:24:38 pm »

A week or so ago, a "solar cycle path" was opened near Maartensdijk in the province of Utrecht, Netherlands.

The project costs €3.3m, and generates enough power for 3 homes.

When I saw the press release, I wrote a long twitter thread about how it's basically a shit idea, purely from a amount of power from the angle of the cells, and the cost.

You can read that thread here:

https://twitter.com/quixoticgeek/status/1416178859544829957

Since then I found myself cycling across it at the weekend. I hadn't realised it was on my route until I approached it.

I took a video of riding along it, which you can find here:

https://www.youtube.com/watch?v=5tIyv8S74fM

I also took some photos.



It looks on first approach like the standard concrete panel construction, but slightly the wrong colour, then as you get closer you realise it's translucent glass. The surface has an interesting texture. It reminded me of woodchip wallpaper, and chipseal.



My biggest thought when I saw the announcement was it would be slippery. But I'm pleased to see it shouldn't be too bad. Heavy rain and long term wear may effect this.



Up close you can see the texture of the surface.



Ultimately this is a €3.3m vanity project, and a gimmick. Given you could generate the same power from the roof of 3 homes, and the cost per house would be no greater than €25k per house. I don't understand why anyone would want to do this. It doesn't make financial sense. It doesn't make energy efficiency sense. If we had completely exhausted every other suitable rooftop, then it may be worth considering other areas like this, but given 99.9% of the roofs I can see from my window are devoid of solar, we're a long way from that point. That €3.3m could get a lot of roof top solar. And if we really did want to get solar from this cycle path, we'd get a higher yield by building a cover over the top covered in solar panels, which would also protect us from the rain...

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Kim

  • Timelord
Re: The road to solar...
« Reply #1 on: 27 July, 2021, 09:37:12 pm »
Solar frikkin' roadways!

I think it's daft[1] for all the reasons you do, but it was probably worth someone somewhere building one to prove the point.


[1] I concede there may be some edge case where a large expanse of lightly-used tarmac that can't be covered (racing track or an emergency runway or something maybe?) might be usefully employed to generate electricity, but it's never going to make sense for roads or car parks.

Cudzoziemiec

  • Моя планета голубая, я люблю тебя и обнимаю
Re: The road to solar...
« Reply #2 on: 27 July, 2021, 10:12:48 pm »
I'd actually heard of this idea though I can't remember in what context, so it's interesting that you've encountered one. I'm glad it wasn't too bad to ride on, it looks as if the joins between panels might have got a bit annoying in a thunk-thunk way.

Looks like a pretty silly way to use PV panels. I suppose if you have some spare and you're building a road anyway, it isn't a total waste...

Plus it gives me an excuse to play with teh Jarvis.

It reminded me of woodchip wallpaper, and chipseal.
Your road was very poor,
With woodchip on the floor.
Riding a bike through a city is like navigating the collective neural pathways of a vast global mind.

LittleWheelsandBig

  • Whimsy Rider
Re: The road to solar...
« Reply #3 on: 27 July, 2021, 10:13:42 pm »
The proof of concept of almost everything is overly expensive and not particularly efficient.

A solar panel frame over the top of a normal cycleway would be pretty expensive too. Uplift from wind is a major issue and would need decent foundations. The frame would need to be tall enough for fairly large maintenance vehicles to fit underneath and the supports be able to withstand a low speed impact. At least it is easier to clean or maintain solar cells at ground level.

Don’t get me wrong, this is a silly idea but the issues need to be demonstrated. This will do so.
Wheel meet again, don't know where, don't know when...

Re: The road to solar...
« Reply #4 on: 27 July, 2021, 10:20:27 pm »
"The project costs €3.3m, and generates enough power for 3 homes. "    WTF?    Is that really a useful spend of money?



It'd also be nice if any of the photos you post actually display instead of just being blank boxes.

Re: The road to solar...
« Reply #5 on: 27 July, 2021, 10:20:47 pm »
I suppose if you have some spare and you're building a road anyway, it isn't a total waste...

But the foundation must be much more flat and solid and the top surface needs to be made out of glass, which we don't normally use for roads for countless obvious reasons.

LittleWheelsandBig

  • Whimsy Rider
Re: The road to solar...
« Reply #6 on: 27 July, 2021, 10:24:58 pm »
I suppose if you have some spare and you're building a road anyway, it isn't a total waste...

But the foundation must be much more flat and solid and the top surface needs to be made out of glass, which we don't normally use for roads for countless obvious reasons.

What makes you think that there is any difference in the foundation needed?
Wheel meet again, don't know where, don't know when...

Kim

  • Timelord
Re: The road to solar...
« Reply #7 on: 27 July, 2021, 10:26:33 pm »
What makes you think that there is any difference in the foundation needed?

Experience of BRITISH cyclepaths? :)

LittleWheelsandBig

  • Whimsy Rider
Re: The road to solar...
« Reply #8 on: 27 July, 2021, 10:27:56 pm »
Dutch cyclepaths are built to a decent standard (at a commensurate cost). Guess where this one is.
Wheel meet again, don't know where, don't know when...

quixoticgeek

  • Mostly Harmless
Re: The road to solar...
« Reply #9 on: 27 July, 2021, 10:30:20 pm »
"The project costs €3.3m, and generates enough power for 3 homes. "    WTF?    Is that really a useful spend of money?



It'd also be nice if any of the photos you post actually display instead of just being blank boxes.

they are hosted via twitter, you can find them all via this thread on twitter:

https://twitter.com/quixoticgeek/status/1420109549093232641

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: The road to solar...
« Reply #10 on: 27 July, 2021, 10:34:22 pm »
https://www.dutchnews.nl/news/2021/07/worlds-longest-solar-panel-bike-bath-opens-in-utrecht/ states: 'The cost of the project is put at €1.3m...' and reckons that it has '...the ability to create enough electricity to power 40 homes.'

Re: The road to solar...
« Reply #11 on: 27 July, 2021, 10:38:39 pm »
What makes you think that there is any difference in the foundation needed?

It looks to me like that road has to made to very precise dimensions to make the glass panels fit on the top. Even Dutch cycle paths are fuzzy things with complex compound curves and doubtless shift over time.

LittleWheelsandBig

  • Whimsy Rider
Re: The road to solar...
« Reply #12 on: 27 July, 2021, 10:46:11 pm »
The solar panels are installed on straight sections of the path and inset into/ surrounded by a flexible or rigid pavement material that is probably laid afterwards. They are not fitted to complex geometry sections with reverse curves. This isn’t rocket science.

https://inhabitat.com/solaroad-the-netherlands-unveils-worlds-first-solar-cell-paved-bike-path/ shows interlocking reinforced concrete panels that would be fairly resistant to local subsidence messing up the alignment.
Wheel meet again, don't know where, don't know when...

Kim

  • Timelord
Re: The road to solar...
« Reply #13 on: 27 July, 2021, 10:48:23 pm »
Surely it's not much different from laying paving slabs?  Okay, people manage to fuck that up on a depressingly regular basis, but that doesn't mean they don't work.

quixoticgeek

  • Mostly Harmless
Re: The road to solar...
« Reply #14 on: 27 July, 2021, 10:49:23 pm »
https://www.dutchnews.nl/news/2021/07/worlds-longest-solar-panel-bike-bath-opens-in-utrecht/ states: 'The cost of the project is put at €1.3m...' and reckons that it has '...the ability to create enough electricity to power 40 homes.'

Doing my research, I think I may have pulled the price for this project from the wrong article.

https://www.theguardian.com/environment/2014/nov/05/worlds-first-solar-cycle-lane-opening-in-the-netherlands

40 homes at €25 per home, is still €300k less...

J

Edited to fix my maths.
--
Beer, bikes, and backpacking
http://b.42q.eu/

LittleWheelsandBig

  • Whimsy Rider
Re: The road to solar...
« Reply #15 on: 27 July, 2021, 10:53:09 pm »
How much does a normal Dutch cyclepath cost for that length? Not too far off that, is my guess.
Wheel meet again, don't know where, don't know when...

Re: The road to solar...
« Reply #16 on: 27 July, 2021, 10:59:45 pm »
https://www.dutchnews.nl/news/2021/07/worlds-longest-solar-panel-bike-bath-opens-in-utrecht/ states: 'The cost of the project is put at €1.3m...' and reckons that it has '...the ability to create enough electricity to power 40 homes.'

Doing my research, I think I may have pulled the price for this project from the wrong article.

https://www.theguardian.com/environment/2014/nov/05/worlds-first-solar-cycle-lane-opening-in-the-netherlands

40 homes at €25k per house, is still €800k less...

J

40 homes at €25k per house is €1m.  What is that €800k less than?

quixoticgeek

  • Mostly Harmless
Re: The road to solar...
« Reply #17 on: 27 July, 2021, 11:02:22 pm »
https://www.dutchnews.nl/news/2021/07/worlds-longest-solar-panel-bike-bath-opens-in-utrecht/ states: 'The cost of the project is put at €1.3m...' and reckons that it has '...the ability to create enough electricity to power 40 homes.'

Doing my research, I think I may have pulled the price for this project from the wrong article.

https://www.theguardian.com/environment/2014/nov/05/worlds-first-solar-cycle-lane-opening-in-the-netherlands

40 homes at €25k per house, is still €800k less...

J

40 homes at €25k per house is €1m.  What is that €800k less than?

300k less. I'm going to bed I am clearly not awake.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

fboab

  • Behind every Great Woman there's a man inna hat
Re: The road to solar...
« Reply #18 on: 28 July, 2021, 10:36:29 am »
There already been solar roads in France. I've ridden on it.

obviously a while ago
Presumably the dutch design doesn't have to hold up to tractor traffic.
TSS is not Total Sex Score, Chris!

ravenbait

  • Someone's imaginary friend
  • Pudge controls the weather.
    • Someone's imaginary friend
Re: The road to solar...
« Reply #19 on: 28 July, 2021, 10:45:55 am »
I deal professionally with infrastructure. Having an asset in the control of a company or national agency where maintenance can be properly financed, scheduled, and, where necessary, enforced, is worth more than 300k.

Sam
https://ravenbait.com
"Created something? Hah! But that would be irresponsible! And unethical! I would never, ever make... more than one."

Re: The road to solar...
« Reply #20 on: 28 July, 2021, 10:55:49 am »
Is the 40 homes claim year round after years of dirt and degredation, or on a really sunny day under ideal conditions when the panels are clean and brand new?

(It wouldn’t surprise me if it’s based on the gross rating of the bare panels without even the attenuation of the glass surface and without accounting for the far from ideal horizontal mounting)

Cudzoziemiec

  • Моя планета голубая, я люблю тебя и обнимаю
Re: The road to solar...
« Reply #21 on: 28 July, 2021, 11:06:12 am »
I deal professionally with infrastructure. Having an asset in the control of a company or national agency where maintenance can be properly financed, scheduled, and, where necessary, enforced, is worth more than 300k.

Sam
Shshsh! You might give Sustrans dangerous ideas!

Solar powered kissing gates on the cycle path?
Riding a bike through a city is like navigating the collective neural pathways of a vast global mind.

Re: The road to solar...
« Reply #22 on: 28 July, 2021, 11:09:13 am »
There already been solar roads in France. I've ridden on it.
I rode a stretch several times at the 2017 Semaine Federale in Mortagne au Perche.  This was the road itself, so fully load bearing.

ravenbait

  • Someone's imaginary friend
  • Pudge controls the weather.
    • Someone's imaginary friend
Re: The road to solar...
« Reply #23 on: 28 July, 2021, 11:45:17 am »
Shshsh! You might give Sustrans dangerous ideas!

Solar powered kissing gates on the cycle path?

Sustrans and I haven't been on speaking terms for about 20 years, now.

Sam
https://ravenbait.com
"Created something? Hah! But that would be irresponsible! And unethical! I would never, ever make... more than one."

Re: The road to solar...
« Reply #24 on: 28 July, 2021, 11:45:54 am »
It's 330m long and about 3m wide -- 40 houses gives about 25m2 per house. As rooftop panels that might give a 3-4 kW, but laid flat, under glass, with a rough, dirty surface it must be less than that. It's not enough for high power things like electric showers and hobs, it might even strugle to supply a kettle. The inhabit.com link posted earlier suggests a 100m path might power just 3 houses which sounds more plausible. The wikipedia page is not encouraging https://en.wikipedia.org/wiki/SolaRoad