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We don’t need solar roadways, we need to help unleash current solar panels

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Wow. A campaign to build a prototype of a parking lot made out of solar cells just raised over $1.5 million on Indiegogo. Over 36,000 people put money into the project.

While it’s a cool idea — and the project is accentuated with well-produced videos and a variety of nicely Photoshopped images — the world doesn’t actually need solar roadways. It needs to support the emerging boom in low-cost solar panels being installed on rooftops and in deserts and fields around the world.

I already wrote a bah-humbug column back in 2010 about the solar roadways project. Back then, the inventor, Scott Brusaw, won a $50,000 award from GE through its smart grid award program. Like with this Indiegogo campaign, the GE award was determined though popular vote on GE’s website; not via experts in business, science and engineering.


As I mentioned in that article, in reality solar roadways that would meet any of the specifications that are being projected would be really expensive compared to the basic solar panels already on the market. Brusaw told TechCrunch in a profile a couple years ago that their prototype project was expected to cost $10,000 per 12 foot by 12 foot panel, which is probably conservative because it was a projection by the inventor before it was implemented.

Rooftop solar panels are at their cheapest time in history right now. And combined with new business models that help customers get the panels installed for free with a long-term electricity contract, a market for solar systems in the U.S. has opened up like never before. There were more solar panels installed in the U.S. in the last 18 months than in the last 30 years.

It’s a huge market. The market value of all solar panel installations completed in 2013 in the U.S. was $13.7 billion. And the good news is that it’s just getting started. In 2014, researchers predict 26 percent growth in the solar panel market in the U.S. with installations reaching nearly 6 GW.

SunPower California solar ranch

The technology to produce reliable and available solar energy is already here and has had many decades of market fluctuations and development to get it down to the price point where it is today. What the world needs now is more ways to open up access to capital for solar panel installations on roofs and on empty land, more utilities embracing distributed solar, grid upgrades to get ready for the coming solar panel boom, and more innovative business models to get these solar panels out there. One of the main things is we need to reduce the “soft costs” around solar panels, which can make up half of the cost of the solar system.

We don’t need new prototype technology to ruggedize solar panels to completely cover roadways. I’m not even going to go into the argument about whether or not this technology is feasible to meet the somewhat ridiculous (albeit it tongue-in-cheek) claims from the Indiegogo campaign.

Next-generation solar materials beyond the current solar panels will also be important one day and will need many more years of development to get them to the same low price point of the current solar panels. Those types of science projects are getting government grants, and some investment from large power companies.

An inventor that is interested in experimenting with this solar roadway technology is interesting, and clearly he’s an innovative guy. And if companies want to give his group some small grants to test out prototypes of the tech, I’m all for that.

But this project should not be getting any large amount of public funds, and any Indiegogo donators should have all the facts before donating to this project.

204 Responses to “We don’t need solar roadways, we need to help unleash current solar panels”

  1. Todd A. WEaver

    Has anyone ever herd of the Lincoln Highway. Back before we were all driving cars and many were riding wagons and horses still. The concrete industry laid seed miles of road to promote the possibilities of the future. Some of the short sighted thought patterns displayed here shows we as Americans have lost our sense of what could be. I personally think solar parking lots is a good way to use dead space to produce something besides heat that warms the cities that occupy all that sq footage of parking area. Private money put up the 1.5 million it took 36000 people. How about if 5 or 6 million just donated 2 dollars per week for a year to set up some seed miles. That would be 560 million a year and no one would miss the money. You might create some jobs, you would create some clean energy, you might be able to even create new industry by using the video aspect of the panels. America has always been the place for the possible. Quit trying to end that. Possible only happens when you do the unthinkable.

  2. 0ctatron

    Seriously? there’s article against solar roads? Ahh Illuminated roads negate the need for overhead street lights with objects on road detection, Heat, but only enough to keep the road above freezing for safer surfaces in snow, power collection, three times what the country needs! And one thing they haven’t considered is using this new found power to power vehicles directly through magnetic induction which would MAKE BILLIONS MORE!! all the cash flowing into our own country instead of Saudi Arabia. Jeez the jobs made alone from up-cycling old computer parts would do the job.. Start with major highways and work your way down.. Some people just need to think a bit further ahead then oh no it’s gonna cost money!

    • muddmike

      The cost is not the important part. The important part of this plan is that it is NOT going to work. The panels will not last the 20+ years they claim. They show no evidence of having done durability testing of the glass. They did a tensile strength test which uses a hydraulic ram to slowly put pressure on a glass panel. When trucks are going to drive over these the force is going to be rapid and not only up and down, but sideways. They also did an impact and traction test on brand new panels.

      On the SR site they give all of the info needed to show that the glass will be scratched by sand and rocks. Sand is quartz. When it is scratched it will reduce the light getting to the solar cells and also the light coming out from the LEDs. This scratching by millions of tires each year will grind down the texture needed for traction, so then the panels will be slick as ice when wet. Tempered glass gets its strength from the surface being in tension due to rapid cooling. When this surface is scratched through, the strength is gone and the panels will break. In heavy traffic I doubt any of the panels will last more than a year or two.

      These panels consist of a glass top on a steel box. This is the same design as a solar oven. They know this and you can find on their site that they plan to use processors rated for 125 C, which is above the boiling point of water. One problem with solar cells is that when you heat them up they get less efficient. This is why solar panels on roofs are raised so air can circulate and keep them cool. Solar cells are rated at 25 C. At 125 C solar cells are less than 50% as efficient as at 25 C. Thus their 52 watt panels become 26 watt panels. The scratches and dirt, the fact that they are laying flat instead of being tilted toward the sun, an many of them will be shaded by buildings, trees or vehicles means the actual average out put of these panels will be less than 10 watts each, in the summer, and even lower in the winter.

      The solar roads people have benefited from the fact that most humans are scientifically and technologically illiterate and have almost no critical thinking ability. They make wild, unsubstantiated claims for their product and people eat it up.

      The biggest problem is that once they fail, and they will fail, people who are against renewable energy are going to respond to any new project as just “another solar freakin’ roads plan!.” This will hinder renewable energy for at least 10 years.

      If I were working for the fossil fuel industry, I would be pushing this plan every day.

  3. dallas

    et tu brute…. sounds like you may be a bit jealous… giving small notations of grace, while not interested at all in the indiegogo project… so maybe you don’t live in a snow driven state that has snow covered and icy roads that could be eliminated…. or may you’re not a tesla follower, maybe you have stock in oil companies.. I’m not sure which it may be, the oil industry should have great concerns about this, and they will probably discredit the whole idea. they have in the past…. in 1968 a test carburetor was put in an gm oldsmobile that generated 38 mpg. that’s in a large V8 engine…. IN 1968 yet the oil industry would not allow auto manufacturers to us it… just think of the use of that carb in a 4 cylinder engine in 1968, or now for matter. the tesla theory would be brought to life with the realization of tesla’s experiments with the electric auto. this world would be clean, no exhaust poisons in the air, people would live a much healthier life and the earth would also…

  4. Rebecca Holmberg

    This article ignores the other potential benefits of Solar Roadways, which include collecting and cleaning stormwater runoff, a major source of water pollution, bringing cable internet to rural communities, reducing traffic accidents, and, most importantly, helping to decentralize the power grid of the United States.

    Own stock in a rooftop solar panel company, perhaps?

    Please watch the videos and donate here:

    • muddmike

      Yes, they talk about pumps and check vales and treatment plants, but they don’t even begin to list what this is going to cost. Nor do they estimate the electricity needed to run all of these pumps to pump the water up over hills.

      I did a quick calculation. I assumes 10 inches of rain per year, which is low for the average. of the US. This small amount would yield 5 TRILLION gallons of water to treat. They make is sound like they are going to put in some magic filter.

      Here is the cost of one sewage treatment plant. While sewage treatment is more involved than storm water treatment, it gives you a ballpark figure.
      “Construction of the Columbia Regional Wastewater Treatment Plant was completed in 1983 and required approximately 200 man-years of effort in moving 600,000 cubic yards of earth and rock (enough to fill Faurot Field to the top of the bleachers), placing 75,000 tons of concrete, installing 40,000 lineal feet of piping with 234 valves, and providing $3 million worth of equipment. The total construction cost for the Columbia Regional Wastewater Treatment Plant was $21 million. An additional $30 million was spent for construction of new interceptor sewer lines to convey wastewater to the new treatment plant. The original plant design capacity was 13 million gallons per day. ”

      13 million gallons a day is about 5 billion gallons a year. This cost more than $50 million. Thus we would need 1,000 plant of this size to treat the runoff. That alone would cost $50 billion. IN practice plants that big would be too widely spaced for many areas, so we would probably need to build maybe 5 ,000 to 10,000 smaller plants, which would cost more than the fewer large plants, and would cost more to operate. I have not been able to get numbers for the cost of operating these plants.

      Yes, they are promising the moon. Interestingly they have never listed how much it is going to cost to build that 31,000 miles of that concrete panel support with precision mounted bolts, the drain channels and the cable channel. Nor have they mentioned the cost of tearing up the existing roads, and probably laying down a new base since the existing base for the road is probably not going to work.

      Also you showed your classy side. “Own stock in a rooftop solar panel company, perhaps?”

      Ad hominem attacks do not improve your argument. I know the solar roads people use them, but they usually indicate that you realize that your argument is weak.

      Probably somewhere is my retirement account there is maybe $100 invested in solar panel companies, so I am certainly doing this to become rich. I might get a dollar or two more.

  5. Nick Vaidyanathan

    Yes. Clearly we’ve never seen expensive prototypes/early generation technology that has its costs driven down by investment and refinement of methods.

    (*cough $10K PCs in the 1970s, $1K cell phones in the 90s*)

    It’s interesting to see a technical reporter argue that we don’t need disruptive innovation, we just need to focus on what we already have.

  6. Frank Baca

    Solar roads are just in the infancy stage and will take years, even decades to become ‘reality,’ if ever.
    This article reads like an attack on a “New technology.” The same way the Oil industry attacks ALL “alternative” energy. Sad that an industry that has endured ignorant attacks has some who have resorted to the same…against themselves.

  7. Brandon Snyder

    I’m glad you recognized that solar panels on houses are cheaper than on roadways. What you fail to discuss is that the US has a predisposition to support homes as a personal responsibility and roads as a social one. You can get subsidies for your solar panels on your house, but the homeowner is still responsible for the maintenance, installation, etc. With roads, society picks up the bill. It is a few pennies from everyone. It is a return to a New Deal, society taking care of society, view.

    tl;dr — US is selfish. More productive for solar to pursue socialized advances instead of localized ones.

  8. Rixandros

    I think that comparing solar roads with regular solar panels is misleading.
    Solar roads’ most relevant aspects, for me, are
    1) Roads are integrated with each of all the largest-scale industries: automotive and oil. The total impact of this solution has to be analyzed considering all the modifications that such industries should experience, starting from the tires industry. Tires industry has developed connecting vehicles to the ground and since 100 years the ground has been asphalt. This is just one of the many examples that could be made.
    2) Solar roads has the potential to integrate che automotive, the oil and the energy industries. The effect as all to be explored
    3) Solar roads, according with what I understood from this extremely well done commercial, have the potential for self development: if the frame of the unit is sufficiently well done it can host different technologies every time a relevant innovation arises; the cost of this change is relatively small, compared with today’s standard roads: think about the ease of subsituing a wire in a solar road rather than in standard roads.
    3) nowadays solar panel are the equivalent of a battery that is convenient to put on roofs because untill now roofs seemed the only reasonable place to put panels. If a technology permits to identify more convenient areas of coverage it’s correct to follow that road

  9. Dave Kozin

    The real conservation should be whether we want “smart roads” or not. The concept of using solar IN the road is so gimmicky and such a bad idea, for both financial and technical reasons. We could put solar so many other places, and instead look at a smart road that doesn’t involve solar if we want all the benefits that smart roads would bring.

  10. Einstien

    There’s thousands of miles of highways, freeways in the US. Why not installed miles and miles of solar panels between the north-south bound lanes. Its usually just a concrete barrier that divides the two highways. We wouldn’t need to tear up the pavement to install solar panels on the ground. One earthquake and it will be costly repairs. Installing solar panels on the concrete barriers between Freeways just means bolting down panels perk up on a steel pole.

  11. whynot

    I see your point, but at least people are excited about solar roadways and taking it upon themselves to spread word, etc. Public excitement and proactivity are vital to the implementation of renewables, and this project is apparently more inspiring than traditional solar panels. So if people are willing to part with their time and money for this project (and in the process driving renewables forward) when they won’t for others, why not?

    • muddmike

      The fact that this terrible idea is so popular is the worst part of it. There are so many reasons that this plan will never work, that is is already doomed to failure. I have posted some of the bigger reasons on this page and on others. The masses of scientifically and technologically illiterate people who have weak or no critical thinking skills, have fallen for this.

      When (not if) it fails, people who oppose renewable energy will only have to use the following phrase when a new renewable energy plan comes out, “This is just another solar freakin’ roads plan!” That will be all that it takes to slow down renewable energy for at least the next 10 years after this idea is shown to be a failure.

      This plan is going to drive renewables backwards, not forwards.

  12. Tobias

    SolarRoadways may very well be one of the worst ideas in the renewable energy field I heard about.

    Why don’t put the panels on the side of the road? Where they can be tilted and not being under thick glass that is going to be scratched.

    You don’t have to build a road of glass if you want to make it warm and melt ice. You can put cables under asphalt and warm it up. Why do people just do that on Icelandic parking lots. Huge amount of energy means huge costs.

    Great dream. Worst engineering ever.

  13. Michael Neuman

    The gist of the Solar Roadway project, as I see it, is that if we could make full use of existing developed surfaces, there would be no need to develop “empty land.” I won’t argue whether solar roadways make sense, but I will argue that we should be developing solar energy on rooftops and other locations that already bear the human footprint. Setting up financial systems to incentivize this over developing new land should be a high priority.

  14. Gavin Peters

    Why should these be opposed goals? Solar everything! Solar the back of my mobile phone so it charges itself, that would be nice.

  15. edith

    I could agree with you if you had not acted like you are just apposed to the opposition. i support any energy that helps to save our plaint. there’s or yours, so lets just do whats right not tern it in to a pissing contest.

  16. Please do not “knock” this – they do MUCH MORE than provide solar power……there is no one single answer to our energy problems – rather than condemn one over the other, let’s just let the cream rise to the top. (I know, you youngsters will not know what I just said…)

    Take a look at others as well… the math – we will need more than one or two sources to win this battle…..

    For example, how about this? LFTR (Liquid Fluoride Thorium Reactor)

    • muddmike

      They promise so much is the reason I doubt them. Above, I have shown that the melting of snow with electricity is not practical anywhere north of the Mason-Dixon line.

      They claim a 20 year (175,000 hour) lifespan for their panels. They have designed their computer electronics to survive 125 C (258 F)temperatures. The panels are a sealed system with no way to dissipate the heat. The sun will turn these into solar ovens. LEDs are rated for a 50,000 hour lifetime at room temperature, at which time the output will be down to 70% of initial output. When heated to 125 C they will degrade to almost nothing in a few years.

      At 125 C the efficiency of the solar cells will also be reduced to less than half of the output at 25 C. Solar panels on roofs are raised so the air behind them can cool the panels.

      There will also be a huge amount of vibration which will cause electrical connections to fail.

      The problem here is that any of the failures will make replacement of the panel necessary. Since these are sealed units, repairing them is going to be more expensive than building a new one.

      The bolts holding down the panels will create strain points. The seal will also limit the lifetime of the panels. The expansion and contraction of the different materials from temperature changes will weaken these seals. If the seals fail and water gets in and destroy the panels.

      I would be amazed if even 1 out of 1 million panels lasts the advertised 20 years.

  17. 0.3E9m/s

    Here in California, the power company doesn’t have to buy the surplus power from my rooftop solar panels. But they’ll gladly take it for free. That’s what has to change.

  18. John Keeber

    I just looked into “Going Solar” on my 990 sq. ft. home. The price I got was between $10,000.00 and $15,000.00 U.S. I live on SSD, to cover that price would take between 20 and 30 years! I am 60, so I guess I will continue to get screwed by the gas and electric companies.

  19. Kyle Christy

    The majority of people commenting have missed one of the major points of implementing this.

    Firstly, if you work on “more ways to open up access to capital for solar panel installations” as the author suggests… then in turn you are opening up ways to use solar panels on roads just like anywhere else. But the biggest point is land management. There is only 1 truly limited resource on earth… and that is land. I don’t want to use up countless thousands of beautiful useable land to plant down big solar farms, or even just use up space in my back yard! That’s such a waste! We already have millions of miles of roads and parking lots that are already taking up space doing nothing but allowing us to drive around. They are already there using up our valuable space, why don’t we make them capable of doing something else besides just being driven on? Even if we just start by using it on driveways, parking lots, and just low speed limit roads to start with we would be adding a huge amount of sustainable clean energy to the grid.

    Even though right now, in the short run, it is still more efficient use of money to get access to just be able to put solar panels on every roof in America (which is perfect and still achieves the same thing, the roof is mostly unused space anyways), you can’t just stop research, development and grants for stuff like this. Even though it may seem far off from being implemented, you have to start somewhere, and this is obviously a great idea for how to use our otherwise limited use roadways.

  20. Casey in Davenport

    Katie, you are missing the point here. It’s not simply about solar energy, this about ENDING wars over limited resources. This is about high speed internet proliferation. This is about reducing CO2 emissions to a level our world can handle. This is about expanding this nation’s workforce into a scientifically literate one that can install what we need to end our recession and boost us to a new age of technological superiority this country needs to stay competitive around the world. More practically, it would help save lives from pedestrian accidents. Hell, it would make a “Wi-Fi blanket” over this country. You could connect and use the highway as a damn screen for you to read the news while you sat in your driverless car! ! ! The possibilities for ingenuity and creation that would build new industries are as endless to us as the suns energy (for another 4-5 billion years that is). So effectively endless. In conclusion, this is a project that needs and deserves massive funding and development. I hope we embrace it and use it to its full potential! Furthermore, we should put the panels on our homes while we are at it. :)

  21. Jasun

    I also agree that there is much more benefit to this idea than just energy production. Road maintenance cost, especially in states that freeze is a process that could use some innovating. The process of re-surfacing a road only to KNOW it has to be re-done again in about 5 years, is not a good way to keep advancing into the future. Re-programmable lanes and layouts, warning signs due to obstructions, all real-time; save money in so many more ways than just making electricity from the sun. Plus, I disagree with harvesting sunlight by spreading panels across open un-developed fields. We should do more to preserve natural landscapes and not build cover them up.
    And the cost of this idea, much of it would come from coat-shifting funds already spent on infrastructure projects. Jobs will go away, and new ones will replace them. Its called progress.

  22. Robert

    I agree as I have solar on my roof already. It is only a 2.7 kw system and the first year I only saves about $250 on my electric bill. The second year that savings went to over $600 with almost the same usage. This was because SCE had a rate increase. This year I expect even more savings because of another “rate” increase through manipulation of the size of the lower tiers. I see no need to use deserts or fields as there are more than enough roofs. And the best part is the transmission lines are already in place. One added benefit is that the rooms under the panels are cooler because the roof no longer heats up as much. There is even the possibility that the roof will last longer because of less sun exposure, a nice side effect.

  23. mel baron

    I think everyone is missing the big picture.Can you imagine what 1.5 million in regular solar panels installed would produce in power.Please don’t get me wrong,i think the road solar panels are a great idea,but the cost to produce them versus the power they put out would outweigh their potential.I installed a 6000 watt system on my home and I live in a very sunny state.The payback is around 15-18 years.I do get some pleasure from the fact that I am beating up the electric company,but the fact still remains $$$$ spent to savings and payback are something that really needs to be looked at.

  24. I’m not saying I’m for the project, but the article don’t hit on other cost points.
    If the solar roadway was installed just where roads are already deteriorating, how much more is it to install versus rebuilding the highway?
    Would installing the panels just in the shoulder areas work?
    As the panels are said to be extremely durable, what is the life expectancy versus the normal surfacing for the area?
    Obviously rooftop panels are cheaper, but it would be interesting to see a side-by-side comparison for doing a ten mile stretch of a four lane interstate.

    • muddmike

      Only the solar roads people say they are durable. Anyone who is scientifically and technologically literate says otherwise. They do not list any durability testing. In reality the glass is going to be the weak point.

      Yes, tempered glass, when new can hold up a truck that moves slowly onto it. The tensile strength test they did uses a hydraulic ram to slowly add force to the panel. They don’t say what shape the panel was that was tested and how it was supported. There current panels have four large hole drilled through them. which will concentrate stresses. They will also be supported by what looks to be a half inch ledge around the edge. That will be a stress point. SInce glass is an amorphous substance every time it is flexed it degrades a little. A reasonable level of traffic on a city street is 10,000 vehicles per day so that is 20,000 flexes per day. In a year that adds up to more than 7 million flexes. In 20 years that is 140 million flexes.

      On there site in the muddying the freakin’ water page (They call it the clearing the freakin’ air page, but it doesn’t.) they give all of the info needed to show that their panels will be scratched by sand and rocks that get on the road surface and are ground into the glass by tires. They list glass with a hardness of 6 and quartz with a hardness of 7. Thus sand, which is fine pieces of quartz, will grind down the glass. This will make it frosted glass, which will limit the light getting to the solar cells as well as the light coming out from the LEDs. The sand will also grind down the texture which is needed for traction. Thus when the texture is gone and the glass is wet the cars might as well be driving on ice. So much for saving lives. Tempered glass gets its strength from the surface being in tension. When that surface has been ground away the strength is also gone.

      The panels will also be pounded and vibrated by every vehicle driving over them. All of the electronic connections will be shaken and will eventually fail. If any part fails the whole panel must be replaced because they are sealed units.

      I have no financial interests in any other type of energy companies. I am only trying to convince the scientifically illiterate masses that the solar roads are a really bad idea.

      If I were shilling for the fossil fuel companies, I would be supporting this awful plan. They have made so many outlandish claims, and It is now so visible that WHEN (not if) it fails, this will taint the whole renewable energy industry.
      From then on every new idea will be labeled. “This is another solar freakin’ roads project!” No one will even remember what Solyndra was.

      This will then slow down the necessary process of getting away from fossil fuels.

      I have another 20+ intrinsic problems with the solar roads plan that cannot be engineered around. They are flaws in the basic plan and the materials involved.

      To the scientifically and technological illiterate masses I have to repeat. Science and technology are NOT MAGIC. They have to work within physical laws. Just wishing hard enough will not make the solar roads a success.