Solar power embedded in roads melt ice, make heat:

http://www.cnn.com/2011/TECH/innovation/01/19/smart.roads/index.html?iref=obnetwork

5 megabucks per mile but it generates electricity for city use when it is not snowing.

Originally posted by sonhouse
http://www.cnn.com/2011/TECH/innovation/01/19/smart.roads/index.html?iref=obnetwork

5 megabucks per mile but it generates electricity for city use when it is not snowing.

I am still not convinced that it is in any way more cost effective than solar panels on the roof etc. As for melting snow, I suspect that snow plows and salt are cheaper than electric heaters built into the road.

Originally posted by twhitehead
I am still not convinced that it is in any way more cost effective than solar panels on the roof etc. As for melting snow, I suspect that snow plows and salt are cheaper than electric heaters built into the road.

The problem with salt is so much is used it is actually salinating the drinking water, contaminating wells and such. So any solution that melts ice without using calcium chloride or sodium or magnesium choride is much better in my view. One question is what happens when there is a heavy snow or ice, how much light would penetrate that stuff to get to the solar panels in the roadway. And how much heating would it take to clear ice from the roadway, how many kw per mile, etc. Still sounds better than using salt of whatever kind. Think about the amount of energy to be tapped that way, 1 mile by say 50 feet, 250,000 square feet and generating say 20 watts per square foot (just a guess) would amount to 5 megawatts during daylight. There would still be the problem of energy storage to last through the night or else go back to salt and scraping.

Originally posted by sonhouse
So any solution that melts ice without using calcium chloride or sodium or magnesium choride is much better in my view.

Surely you mean a solution with reasonable costs.

I think you should separate the solar panels idea from the heaters in roads to clear snow idea and only combine the two when looking at cost savings when they are combined.

I think solar panels in roads is not the most cost effective way of making and deploying solar panels.
I think solar panels are most cost effective nearer the equator where there is less snow.
I think using heating to get rid of snow is so expensive that it has not been used on roads or pavements anywhere in the world - why would using solar panels for the job change that? Remember that it would still use electricity which could be used elsewhere so the only saving would be the existence of transport lines.

Originally posted by twhitehead
Surely you mean a solution with reasonable costs.

I think you should separate the solar panels idea from the heaters in roads to clear snow idea and only combine the two when looking at cost savings when they are combined.

I think solar panels in roads is not the most cost effective way of making and deploying solar panels.
I think solar panels are ...[text shortened]... city which could be used elsewhere so the only saving would be the existence of transport lines.

There is also the savings of salinating the roads which wash off and salinate the run off to rivers and streams and ground water. I don't think you know how serious a problem that is.

The idea of using solar on roads has the advantage in one way: no right of way has to be purchased. If solar panels paved the side of the road, new land would have to be purchased, forcing people out of their homes, reducing arable land and the like. Keeping it on the roads would be a great use I think.

Economically you have to take into account the right of way purchase price in the overall equation.

Here is a link to the damage salt is doing to our water supply, in the US at least.

http://www.badwaterjournal.com/Bad_Water_Journal/Road_Salt.html

Originally posted by sonhouse
There is also the savings of salinating the roads which wash off and salinate the run off to rivers and streams and ground water. I don't think you know how serious a problem that is.

You are correct that I know nothing of the problem. I have not seen snow since I was a very young child (four I believe).

However, I am not convinced that it is relevant. Solar panels, do not melt snow. Heaters would be required which would use electricity. I do not see why solar panels in the roads would be the most cost effective way of generating that electricity. I am not even convinced that electricity is the most cost effective heating method. I suspect water pipes under the roads would be more efficient.

The idea of using solar on roads has the advantage in one way: no right of way has to be purchased.
You seem to be assuming solar panels are required along roads. Why?

What is wrong with solar panels on roof tops? What is wrong with solar panels in the desert where the most efficiency can be achieved - including other options such as a power storage solution.

Originally posted by twhitehead
You are correct that I know nothing of the problem. I have not seen snow since I was a very young child (four I believe).

However, I am not convinced that it is relevant. Solar panels, do not melt snow. Heaters would be required which would use electricity. I do not see why solar panels in the roads would be the most cost effective way of generating th ...[text shortened]... the most efficiency can be achieved - including other options such as a power storage solution.

Solar panels in deserts would be great except for one glaring fault: No infrastructure to bring the resultant power to the cities where it would be used. No HV towers in the desert. You would then think, well fripping BUILD them. And they are, but the cost for that project seems to be close to a trillion dollars just for the thousands of miles of new towers and substations and wires and control equipment. It is not a trivial problem.

You are of course right when you say solar panels would not by themselves heat the road, but electric wiring would be much more robust than putting pipes in the roadway and cheaper. You could not use simple water pipes, they would have to be antifreeze added and even that has its limits in really cold places besides the infrastructure of added pumps and such. None of that is needed with simple heating tapes.

One nice effect of having heating tapes in the roadway is when the ice and snow is gone, the electricity can be used for other things since all you want is an ice and snow free roadway, once it is clear of those it doesn't matter what temperature the road is, it does not need heating after that.

Still seems a win win situation. It is a lot easier to build solar into the road than putting them up on buildings because of the structural issues of actually doing that.

Which is not to say that shouldn't be done also, we have to have many renewable sources of energy, wind and wave for instance, which is just solar one step removed.

Fusion energy would go a long way to making us free of fossil fuels but that seems to always be just 20 years around the corner. I just saw an article about an Italian team claiming to get 12 kilowatts out with 400 watts in from 'cold fusion', a claim that seems to fly in the face of reason, especially since they are keeping the process secret and supposedly starting a company to built them commercially. I would not bank too much on such a project, especially considering the secrecy involved. It would be fantastic if such a device was proven but I think I will wait for independent results before I get too excited by such news.

http://www.foxnews.com/scitech/2011/01/24/italian-scientists-claim-cold-fusion-breakthrough/

http://pesn.com/2011/01/19/9501747_cold-fusion-journals_warming_to_Rossi_breakthrough/

And in rebuttal:

http://io9.com/5742290/no-italian-scientists-have-not-discovered-cold-fusion

Originally posted by sonhouse
Solar panels in deserts would be great except for one glaring fault: No infrastructure to bring the resultant power to the cities where it would be used. No HV towers in the desert. You would then think, well fripping BUILD them. And they are, but the cost for that project seems to be close to a trillion dollars just for the thousands of miles of new towers and substations and wires and control equipment. It is not a trivial problem.

The real question is whether or not it is more cost effective. Remember that if the sunlight available is greater in the desert then less solar panels are needed. So its a question of either solar panels + HV towers in desert, or solar panels + more solar panels in northern latitudes.

None of that is needed with simple heating tapes.
Will the solar panels in the road generate enough power to melt the snow even though covered with snow, or must the power be stored or brought from elsewhere? Why do we need the solar panels at all if what we want to do is heat the roads with electricity?
How much electricity is required to heat the nations roads in the winter?

One nice effect of having heating tapes in the roadway is when the ice and snow is gone, the electricity can be used for other things
Now you are confusing me. Do heating tapes produce electricity? Where is this extra electricity coming from that can be used for other things?

Still seems a win win situation. It is a lot easier to build solar into the road than putting them up on buildings because of the structural issues of actually doing that.
I don't believe that. How come almost all solar to date is on buildings not on roadways?

I would not bank too much on such a project, especially considering the secrecy involved. It would be fantastic if such a device was proven but I think I will wait for independent results before I get too excited by such news.
I wonder what benefit they could gain from maintaining secrecy. Surely it would only buy them a year or two whereas the real money to be made is in long term patents etc.

Originally posted by twhitehead
The real question is whether or not it is more cost effective. Remember that if the sunlight available is greater in the desert then less solar panels are needed. So its a question of either solar panels + HV towers in desert, or solar panels + more solar panels in northern latitudes.

[b]None of that is needed with simple heating tapes.
Will the s ...[text shortened]... ould only buy them a year or two whereas the real money to be made is in long term patents etc.[/b]

Electrical heating tape of course does not generate electricity, it is a consumer of power. What I was saying about that indicated the power was available for other things after the snow and ice was melted. Then you don't need to pour more energy into the electrical heating tapes and that energy can therefore be diverted to whatever else you need.

You don't understand the infrastructure problem of putting solar in the deserts. Of course you get more kilowatt hours per year out in Mojave and such but the high voltage power lines have not yet been built to take that power from the desert to where it is needed and that is a HUGE project. Right now there are various high voltage towers around the periphery of the US, not through the central deserts
and that turns out to be a project that will cost several hundred billion dollars, a sum that cannot be met by companies, only massive government projects and that is one of the biggest sticking points of using desert solar.

As for the cold fusion project, I think it is more like a scam where they hope to generate a few million in venture capital and then disappear.

Originally posted by sonhouse
Electrical heating tape of course does not generate electricity, it is a consumer of power. What I was saying about that indicated the power was available for other things after the snow and ice was melted. Then you don't need to pour more energy into the electrical heating tapes and that energy can therefore be diverted to whatever else you need.

But you are painting it as a net power gain when it is really a power loss. Its like trying to market water desalination plants by saying that when they are not running we can use the electricity required for something else.
The fact is that the heaters in the roads require both construction costs and electricity when in operation. The do not at any point produce electricity. The reason for putting heaters and solar panels in the road at the same time is that they can both be put in at the same time (a potential saving on construction) and there would be lower power losses transporting the power to the heater. However, unless the solar panel can produce electricity when buried under snow, then the electricity would be coming from somewhere else when the heaters are in operation.
The very fact that they will get covered in snow (as opposed to sloping panels on roof tops) is one of the major disadvantages of solar panels in roads as they will not operate properly during the period they are covered.

You don't understand the infrastructure problem of putting solar in the deserts.
I do understand it. I am merely asking what the balance of costs is. If you put a plant in a low sunlight area but near the power users you need more solar panels. So what is the difference in cost between those extra panels as compared to the high voltage power lines.

Right now there are various high voltage towers around the periphery of the US, not through the central deserts
and that turns out to be a project that will cost several hundred billion dollars, a sum that cannot be met by companies, only massive government projects and that is one of the biggest sticking points of using desert solar.
Nevertheless it might be cost effective.

Originally posted by twhitehead
But you are painting it as a net power gain when it is really a power loss. Its like trying to market water desalination plants by saying that when they are not running we can use the electricity required for something else.
The fact is that the heaters in the roads require both construction costs and electricity when in operation. The do not at any poin he biggest sticking points of using desert solar.
Nevertheless it might be cost effective.[/b]

It might be cost effective to put up towers in the desert, we may have no other choice. Solar cells still will produce electricity buried under snow, but what they can do is to concentrate the power needed say, 100 meters at a time, where you have say 1000 meters of roadway solar.

When one stretch becomes ice free, the next stretch can be cleared and so forth. If you are in the snow belt you would automatically be in the same place that has high voltage towers so a simple hookup to power lines can be done to get power to the grid when there is no ice on the roads.

The situation with snow and ice is the intermittent nature of these storms. Days and days go by with no snow so on those days the power from roadway solar can be diverted to the grid. With many kilometers available, using these numbers: 15 meter wide roadway, 1000 meters long, 1300 watts/ meter squared hits the earth, so times 0.1, If you use 25 % efficient cells, u could get about 1/10th of the available sun so that works out to about 2 megawatts per kilometer.

The biggest obstacle I see is storing the energy, which would probably be solved by hooking the power into the grid, thereby using the grid as a giant battery, and the grid actually giving the intermittent energy needed when there is ice to clear off the road.

That way, if power is cut to say, 20 percent of what it could get if the snow was gone, the grid makes up the difference and when the roadway is cleared of ice and snow, each section would go back to whatever its maximum power out would be unobstructed.

Since there is not much snow in the desert (not totally true, there is on occasion), such roadways would be more useful in the north and north central US. So if you can get 2 megawatts per kilometer, you get 2 gigawatts per 1000 kilometers, or 2 gigawatts per 625 miles.

10,000 km of roadway could produce 20 gigawatts. There is a LOT more roadway than that in the US. Highway 95 going north and south on the East coast is about 4000 kilometers long by itself, going from Florida to Maine.

It is also a lot more than 15 meters wide. That road alone could develop perhaps 10 gigawatts or more. If it were paved with solar the whole length there would be hundreds of kilometers of roadway not covered with ice or snow, I would say no more than 20 percent of 95 would be covered by ice or snow at any one time. Plus in the spring, summer and fall, no snow at all so it would generate gigawatts for 8 hours a day which can be fed right into the grid.

The cost for that road would be about 7.5 billion dollars US. I would imagine there would have to be at least another billion for control electronics to be able to put power to and from the grid along the roadway, so it could be maybe 10 billion for the whole project.

Seems cheaper than fission plants, each one of those puppies only puts out about one gigawatt, and they cost billions to build.

Originally posted by sonhouse
The cost for that road would be about 7.5 billion dollars US. I would imagine there would have to be at least another billion for control electronics to be able to put power to and from the grid along the roadway, so it could be maybe 10 billion for the whole project.

And the cost for putting more efficient solar panels up to the same total output on roof tops would be much lower as they do not need to bear the weight of vehicles.
You seem to think that clearing snow is the main purpose and the power generated is a bonus. In reality the project is being proposed as solar panels as the primary purpose and snow clearing as a bonus.

Seems cheaper than fission plants, each one of those puppies only puts out about one gigawatt, and they cost billions to build.
My understanding was that only recently has solar caught up with nuclear in price per gigawatt and that low efficiency cells are still more expensive per gigawatt than nuclear. There must be something wrong with your calculations.

[edit]
After further reading, I believe nuclear is still cheaper than solar in all instances, so I fail to see how with the added cost of road construction your calculations say otherwise.

Originally posted by twhitehead
And the cost for putting more efficient solar panels up to the same total output on roof tops would be much lower as they do not need to bear the weight of vehicles.
You seem to think that clearing snow is the main purpose and the power generated is a bonus. In reality the project is being proposed as solar panels as the primary purpose and snow clearing ...[text shortened]... , so I fail to see how with the added cost of road construction your calculations say otherwise.

Nuclear has its own set of post production problems that grow more dangerous with each reactor. Until we solve the problem of safe nuclear waste disposal, we are just borrowing from peter to pay paul. We already have a huge problem with waste in the US, nobody wants it. In places like Russia, they don't care if it is just dumped in a river. Like how the Soviet union dumped hundreds of spent reactors in the black sea just to get rid of them. You want that kind of thing? Does three mile Island and Chernoble strike a bell?

You can't get that kind of environmental disaster with solar. One big problem with solar at least for now is the shortage of pure silicon. Newer thin film cells lets us make more panels with less silicon but at a cost of lower efficiency, at least for now. I see work on the horizon to make all that go away, maybe in 5 years the solar story will be a much more viable option.

Originally posted by sonhouse
You want that kind of thing? Does three mile Island and Chernoble strike a bell?

I am a great supporter of solar over nuclear. But that does not change the fact that your figures appear to be in error. Either nuclear is currently significantly cheaper than solar, or we need to start pressuring our governments to switch right now. I believe even SA is planning a new nuclear plant (and no major solar installations despite having some very good sun.)

Originally posted by twhitehead
I am a great supporter of solar over nuclear. But that does not change the fact that your figures appear to be in error. Either nuclear is currently significantly cheaper than solar, or we need to start pressuring our governments to switch right now. I believe even SA is planning a new nuclear plant (and no major solar installations despite having some very good sun.)

Well good luck with that when they have to get rid of the spent rods. Is there a plan in place to deal with that threat or do they just bury any such concern?