7 ms·

A few things to point out: 1. putting solar on the ground means that it is less efficient (cars blocking rays) than raising it above the roadway and providing s

A few things to point out: 1. putting solar on the ground means that it is less efficient (cars blocking rays) than raising it above the roadway and providing shade to the roadway. 2. Dirt on the panels makes them less efficient, roads are dirty 3. Expensive to fix. It is cheaper to fix asphalt than photovoltaic.

Shivetya 11y ago
It is beyond stupid on so many levels only a politician could love it. The sad part is how much money politicians can waste without oversight, especially on dubious expenditures. They would get so much more bang for their buck putting up a solar array along the highway. However this really sounds as if the politicians bought a bill of goods and simply could not comprehend they don't understand the issues. As in, they are the smartest people they know so they are incapable of being sold a bill of goods that are bogus.
- coderdude 11y ago
  Politicians generally aren't the bumbling idiots us computer enthusiasts would like to imagine they are.
  - TeMPOraL 11y ago
    I prefer to look at it this way: effectiveness of their ideas is one of the least important things they optimize for. They're driven by constraints that have little to do with actual value to society.
  - Piskvorrr 11y ago
    In other words, if it does appear idiotic for all the technical reasons, it would follow other reasons are at play. (Call me a cynic, but "pork-barrel" immediately comes to mind.)
  - tremon 11y ago
    Perhaps not, but it's also quite rare for a minister to be a domain expert in his portfolio.
Retric 11y ago
That's a poor comparison, it's not about efficency at any one stage, it's a question of total cost vs total gain. If the cost of this road surface over it's lifetime is less than traditional road surface plus the equivelent solar cells over there lifetime then it's a good idea.
- cyphar 11y ago
  It won't be. Tarmac is an incredibly well-designed material to use for roads. Glass + silicon is not (to put it mildly). Not to mention that the sheer cost of solar panels makes this a ludicrously expensive project (why didn't they just make a solar farm instead and save some of the money to pay for tarmac -- it's a much better way to spend your money).
  - amelius 11y ago
    It is a pity they will probably find out after 1,000 km, and not after, say, 1 km.
  - Retric 11y ago
    Tarmac is cheap and easy to apply, other than that it's a poor road surface. In heavy use coupled with poor conditions Tarmac can need resurfacing in as little as 5 years (10-20 is more common). Worse, it can significantly increase fuel consumption for heavy vesicles as the road surface deforms. Concrete is better for fuel consumption and can last 2-4 times as long, but needs regular gaps for heat expansion which can cause noise issues and poor ware patterns. It's also far more expensive and end of life roads often spend long periods in poor repair. Glass is actually a fairly competitive surface. Though, to expensive for most uses, people have used to for see though driveways etc.
    - cyphar 11y ago
      > Tarmac is cheap and easy to apply, other than that it's a poor road surface. In heavy use coupled with poor conditions Tarmac can need resurfacing in as little as 5 years (10-20 is more common). Worse, it can significantly increase fuel consumption for heavy vesicles as the road surface deforms. Yes, but because it's cheap this isn't a big problem. Not to mention that glass will not last 5-20 years on a highway. It is much softer than the stones and other crap which will be scraped against it with car tyres. It will start to crack when it's hot. It will lose any grip very quickly (thus making it a public safety hazard) and won't function as a useful solar panel much faster than it will stop working. A driveway and a highway are very different problems to solve. > Concrete is better for fuel consumption and can last 2-4 times as long, but needs regular gaps for heat expansion which can cause noise issues and poor ware patterns. It's also far more expensive and end of life roads often spend long periods in poor repair. Yeah, concrete is good as well. I forgot to mention it. > Glass is actually a fairly competitive surface. Though, to expensive for most uses, people have used to for see though driveways etc. See above. I don't agree. And I don't see why people are trying to convince themselves that it isn't a stupid idea.
Udik 11y ago
Agreed, it seems that the economics simply don't add up. The article is also particularly deceptive, as it claims that 4 metres are enough to power one household, and 1km to "light a settlement of 5000 people". However, that means just powering the streetlights of a settlement of 5000, as 1000/4 = 250 only. It's interesting at least as an example of environmental action purely driven by an attempt to get cheap political support (pun intended). I wonder if such an experiment could at least drive further research and innovation.
- cyphar 11y ago
  I doubt that 4 meters of solar roadway would be able to power a household after 6 months of normal use (not to mention that the placement of solar panels on the road is such a stupid idea that it beggars belief).
JoeAltmaier 11y ago
That's just the start. How about, the worst possible case for transmitting power to where its needed - a huge line. A real solar plant can be put where demand is. Also, the angle of the cells is necessarily straight up. Works on the equator, sucks every other place on the planet. And so on. This is an example of stupid thinking - "Roads are flat; solar cells are flat; lets combine them!" It ignores all the other requirements for a good (efficient, positive return) solar installation.
bendykstra 11y ago
I think you can ignore the effect of shadows from cars. If you look at satellite images of highways, the percentage of the road covered by cars is actually quite small (<5%, by length, I would estimate.) The reduced efficiency due to not orienting the panels at the optimum angle will be much greater. https://www.civicsolar.com/resource/effect-array-tilt-angle-energy-output https://www.civicsolar.com/resource/effect-array-tilt-angle-...
- vilda 11y ago
  Solar panels are connected in series to improve efficiency and reduce costs of inverters. Single panel under shadow degrades the whole set. It behaves as a resistance.
  - bdamm 11y ago
    But it's still only 5% resistant to the 95% providing electro motive force.
  - snovv_crash 11y ago
    Which is why you add bypass diodes. If you don't have bypass diodes, and have enough other cells in series, you can actually burn out a section of panel by casting a shadow on it.

Shivetya 11y ago

It is beyond stupid on so many levels only a politician could love it. The sad part is how much money politicians can waste without oversight, especially on dubious expenditures. They would get so much more bang for their buck putting up a solar array along the highway. However this really sounds as if the politicians bought a bill of goods and simply could not comprehend they don't understand the issues. As in, they are the smartest people they know so they are incapable of being sold a bill of goods that are bogus.

coderdude 11y ago
Politicians generally aren't the bumbling idiots us computer enthusiasts would like to imagine they are.
- TeMPOraL 11y ago
  I prefer to look at it this way: effectiveness of their ideas is one of the least important things they optimize for. They're driven by constraints that have little to do with actual value to society.
- Piskvorrr 11y ago
  In other words, if it does appear idiotic for all the technical reasons, it would follow other reasons are at play. (Call me a cynic, but "pork-barrel" immediately comes to mind.)
- tremon 11y ago
  Perhaps not, but it's also quite rare for a minister to be a domain expert in his portfolio.

Retric 11y ago

That's a poor comparison, it's not about efficency at any one stage, it's a question of total cost vs total gain. If the cost of this road surface over it's lifetime is less than traditional road surface plus the equivelent solar cells over there lifetime then it's a good idea.

cyphar 11y ago
It won't be. Tarmac is an incredibly well-designed material to use for roads. Glass + silicon is not (to put it mildly). Not to mention that the sheer cost of solar panels makes this a ludicrously expensive project (why didn't they just make a solar farm instead and save some of the money to pay for tarmac -- it's a much better way to spend your money).
- amelius 11y ago
  It is a pity they will probably find out after 1,000 km, and not after, say, 1 km.
- Retric 11y ago
  Tarmac is cheap and easy to apply, other than that it's a poor road surface. In heavy use coupled with poor conditions Tarmac can need resurfacing in as little as 5 years (10-20 is more common). Worse, it can significantly increase fuel consumption for heavy vesicles as the road surface deforms. Concrete is better for fuel consumption and can last 2-4 times as long, but needs regular gaps for heat expansion which can cause noise issues and poor ware patterns. It's also far more expensive and end of life roads often spend long periods in poor repair. Glass is actually a fairly competitive surface. Though, to expensive for most uses, people have used to for see though driveways etc.
  - cyphar 11y ago
    > Tarmac is cheap and easy to apply, other than that it's a poor road surface. In heavy use coupled with poor conditions Tarmac can need resurfacing in as little as 5 years (10-20 is more common). Worse, it can significantly increase fuel consumption for heavy vesicles as the road surface deforms. Yes, but because it's cheap this isn't a big problem. Not to mention that glass will not last 5-20 years on a highway. It is much softer than the stones and other crap which will be scraped against it with car tyres. It will start to crack when it's hot. It will lose any grip very quickly (thus making it a public safety hazard) and won't function as a useful solar panel much faster than it will stop working. A driveway and a highway are very different problems to solve. > Concrete is better for fuel consumption and can last 2-4 times as long, but needs regular gaps for heat expansion which can cause noise issues and poor ware patterns. It's also far more expensive and end of life roads often spend long periods in poor repair. Yeah, concrete is good as well. I forgot to mention it. > Glass is actually a fairly competitive surface. Though, to expensive for most uses, people have used to for see though driveways etc. See above. I don't agree. And I don't see why people are trying to convince themselves that it isn't a stupid idea.

Udik 11y ago

Agreed, it seems that the economics simply don't add up. The article is also particularly deceptive, as it claims that 4 metres are enough to power one household, and 1km to "light a settlement of 5000 people". However, that means just powering the streetlights of a settlement of 5000, as 1000/4 = 250 only. It's interesting at least as an example of environmental action purely driven by an attempt to get cheap political support (pun intended). I wonder if such an experiment could at least drive further research and innovation.

cyphar 11y ago
I doubt that 4 meters of solar roadway would be able to power a household after 6 months of normal use (not to mention that the placement of solar panels on the road is such a stupid idea that it beggars belief).

JoeAltmaier 11y ago

That's just the start. How about, the worst possible case for transmitting power to where its needed - a huge line. A real solar plant can be put where demand is. Also, the angle of the cells is necessarily straight up. Works on the equator, sucks every other place on the planet. And so on. This is an example of stupid thinking - "Roads are flat; solar cells are flat; lets combine them!" It ignores all the other requirements for a good (efficient, positive return) solar installation.

bendykstra 11y ago

I think you can ignore the effect of shadows from cars. If you look at satellite images of highways, the percentage of the road covered by cars is actually quite small (<5%, by length, I would estimate.) The reduced efficiency due to not orienting the panels at the optimum angle will be much greater. https://www.civicsolar.com/resource/effect-array-tilt-angle-energy-output https://www.civicsolar.com/resource/effect-array-tilt-angle-...

vilda 11y ago
Solar panels are connected in series to improve efficiency and reduce costs of inverters. Single panel under shadow degrades the whole set. It behaves as a resistance.
- bdamm 11y ago
  But it's still only 5% resistant to the 95% providing electro motive force.
- snovv_crash 11y ago
  Which is why you add bypass diodes. If you don't have bypass diodes, and have enough other cells in series, you can actually burn out a section of panel by casting a shadow on it.