Roads as solar cell collectors

[houlahound]

Thought this was interesting. Wonder if it will be profitable enough to upscale.

http://www.fastcoexist.com/1681562/solar-roads-charging-roads-and-the-future-of-transportation

 

[rootone]

Existing silicon based solar collectors rapidly become very inefficient if they get covered with even small amounts of dust, (or any kind of 'dirt' .
On an open road system it is inevitable that this would happen.

 

[houlahound]

I think a protype in Holland was planned to power two houses it made enough power for three. It was a bike path which is sensible for bike friendly Holland. 70m length if memory serves.

 

[Khashishi]

It makes no sense to put fragile solar panels where they will be run over by 18 wheelers and such.

 

[houlahound]

I would have to give the engineers and planners the benefit of the doubt that they have considered this issue.

 

[SteamKing]

I would have to give the engineers and planners the benefit of the doubt that they have considered this issue.

That's what they said before the Titanic left Southampton bound for New York.

 

[mfb]

I would have to give the engineers and planners the benefit of the doubt that they have considered this issue.

Apparently they did not, because the claims they make are (a) not backed by prototypes and (b) ridiculous. If that concept would have any chance, we would have solar panels everywhere already, but not on roads.

That was a nice marketing idea, but with nothing behind.

 

[houlahound]

Prototype on bike path, some countries have extensive bike paths parallel to roads.

http://mobile.abc.net.au/news/2014-11-13/dutch-unveil-world-first-solar-power-bicycle-path/5888440

More people on bikes should be encouraged, the days of single occupant vehicles eg family car going to heavily populated urban areas to work IMO should be illegal. It is dumb, wasteful and dangerous. Car parks could be turned into green spaces.

Whether these will be used on roadways for heavy traffic is in question, prolly not. Light vehicles like small electric cars possible, bikes already done.

IMO trucks need to be rerouted on truck only roads with special construction. The damage trucks do to roads is ridiculous not to mention the extra risk they carry. Rail and light trucks need to be considered again as freight trains and in fact rail networks have been reduced pretty much everywhere what I can tell.

Where I live coal trucks destroy roads, cause more accidents and cost taxpayers millions to repair.

Coal miners should build railways or their own roads. I am sure the same arguments apply to other mass freight systems.

Urban areas do not need 18 wheelers, they should be illegal.

 

[mfb]

http://mobile.abc.net.au/news/2014-11-13/dutch-unveil-world-first-solar-power-bicycle-path/5888440

70*2.5 meters with approximate 2 hours of vertical sunshine per day would give a theoretical sunshine of 5600 kWh. Harvesting 140 kWh of that is a tiny amount, so the cells are quite inefficient.

Selling those ~10kWh/day to market prices gives about 40 cents per day, or about 150 euros per year. How much did the project cost, 3.7 million? Oh...
Sure, most of it is research, but even under ideal conditions (rooftops with the best angle, no hard surface needed, no dirt, no shadows to handle (this is highly non-trivial!), ...) solar cells are quite expensive. No, that system won't get cheap enough.

 

[houlahound]

In straight economic terms they way you have presented it you are right. Less petroleum fuelled vehicles in cities tho may be more important than yr economics based on current costs.

 

[256bits]

You did use the word profitable, which implies that you were thinking economically viable.

Wonder if it will be profitable enough to upscale

So all one has to do is compare the cost of present day methods and materials for building the bike path, to that of building it with solar panels. I would an extra maintenance cost of cleaning the panels on a regular basis, along with the added electric circuits to where the generated electricity would go. Future estimates of the price for surface panels such as this might be expected to drop from present value due to scaled manufacturing. How much is iffy, but a breakeven point could be somewhat pinpointed. And then there is the life of the product to take into account ( versus present day life of a road surface ).

Add in the environmental aspect of say having to use less electricity from a power plant, a value of customer satisfaction and other non-tangibles and you could come up to a price the public is willing to pay, or subsidize.

I wouldn't say it is an idea completely off the chart.

 

[houlahound]

If clean air became a cost then it would bring the price down.

 

[billy_joule]

If clean air became a cost then it would bring the price down.

We currently put panels on buildings and in solar farms, where they are oriented correctly, stay clean, are unshaded, no structural loading ( barring wind and self weight), and can be maintained without causing congestion. Some systems even rotate to follow the sun as it moves across the sky.
All of these advantages are lost on solar roads, Can you give some advantages?

 

[houlahound]

Advantages,;
optimises limited city space.
Shows will to cleaner air mentality
symbolic / pschological value that people give a dang in science
transport which is dirty to clean transport
Tourist novelty factor, taking a bike ride on a futuristic clean system

Sure not easy to commodify but real none the less.

 

[256bits]

If clean air became a cost then it would bring the price down.

Clean air does have a cost.
Air pollution, whether it be CO2 emissions or particulate matter, does have a cost associated with minimizing of said pollution.
Question is - what is more important? cheap energy if along with it comes uncontrolled poor air quality, or life satisfaction.
We have put all kinds of economic controls, over the years, which are now accepted as being normal and never questioned.
Child labour, workplace safety, hours of work are just a few that quite possibly have a cost of manufacturing goods and services, whether up or down in the short or long term.
No one questions their need.
Places that have cleaned up the waterways through collection and processing of refuge would not consider going back to dumping effluent directly into streams and lakes.
All it takes is initiative and mindset.

 

[mfb]

Advantages,;
optimises limited city space.
Shows will to cleaner air mentality
symbolic / pschological value that people give a **** in science
transport which is dirty to clean transport
Tourist novelty factor, taking a bike ride on a futuristic clean system

Sure not easy to commodify but real none the less.

Apart from the tourist attraction all of those things also apply to rooftops, and we are far away from using all the good spaces there, because we are also far away from building and installing them cheap enough to survive without massive subsidies. Using them on roads would be much more expensive.
Replacing petrol-based vehicles with electric vehicles can be done independently of photovoltaics in the ground.

 

[russ_watters]

Most of the other drawbacks have been adequately discussed, but from the article:

To help prevent accidents, the glass has been given a special non-slip surface.

I'm not willing to believe without data that a "non-slip surface" on glass can be both transparent and provide good traction. Rubber on glass can be high friction when dry, but when wet, the friction drops pretty close to zero.

All in all, I agree with the others that this is a really, really bad idea.

Advantages,;
...
symbolic / pschological value that people give a **** in science
...
Tourist novelty factor, taking a bike ride on a futuristic clean system
[separate post]
I would have to give the engineers and planners the benefit of the doubt...

I wouldn't. It is a fad in Philly to put these clever little stationary sculptures also known as vertical axis wind turbines above the entrances to buildings and around the rim of stadiums. They look nice and green on the website, but they are the but of jokes to the actual visitors, who rarely ever see them spin.

Personally, I think faddish marketing gimmicks are a bad thing to focus on when there are actual problems that need to be solved.

 

[sophiecentaur]

Personally, I think faddish marketing gimmicks are a bad thing to focus on when there are actual problems that need to be solved.

The word "faddish" says it all. It's definitely not an attractive engineering proposition. I once saw, in a second hand shop, a gents' trouser press with a radio on it - a similar waste of time.