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Transportation The Almighty Buck Build

Solar Roadways Project Beats $1M Goal, Should Enter Production 311

Lucas123 (935744) writes "It appears an Idaho-based company that created prototype panels for constructing roads that (among other features) gather solar power, will be going into production after it exceeded its crowdfunding goal of $1M. ... Solar Roadways' Indiegogo project has already exceeded $1.6 million. The hexagonal-shaped solar panels consist of four layers, including photovoltaic cells, LED lights, an electronic support structure (circuit board) and a base layer made of recyclable materials. The panels plug together to form circuits that can then use LED lights to create any number of traffic patterns, as well as issue lighted warnings for drivers. The panels also have the ability to melt snow and ice. Along with the crowdfunding money, Solar Roadways has received federal grant money for development."
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Solar Roadways Project Beats $1M Goal, Should Enter Production

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  • by Cassini2 ( 956052 ) on Saturday May 31, 2014 @09:37AM (#47135321)

    Isn't it impossible for solar cells to melt significant snow?

    The black road surface will effectively capture almost all of the sun's energy. In the northern U.S. and Canada, roads routinely get covered in snow.

    The solar cell can capture a portion of the sun's incoming energy, and potentially use it to power heaters to melt the snow. This approach has several problems. Firstly, the solar cells / heater mechanism is less energy efficient than a black road surface. Secondly, if the snow falls when it is dark, the solar cell will stop working (unless it has some big batteries are present, and even they won't last long in a heavy snow fall.) Lastly, the best sun occurs in the summer, and the snow hits in the winter, when less solar energy is available.

    About the only way a solar cell can keep up with incoming snow is if the solar array is much larger than the area of snow being melted. However, even then, you still have the problem of the solar array getting covered in snow ...

    • by Maury Markowitz ( 452832 ) on Saturday May 31, 2014 @09:46AM (#47135353) Homepage

      > Isn't it impossible for solar cells to melt significant snow?

      Yes. Obviously if there is enough energy in the sunlight to melt the snow, the snow would melt already.

      Heating snow to clear it is multiply-times less efficient than scraping it off with a snowplow.

      This whole idea is the dumbest thing I've seen in years, designed by someone who knows nothing about solar power or road engineering. Ask anyone on the planet who's ever had a re-lay a cobblestone road surface how well they think this will work.

      • by Anonymous Coward on Saturday May 31, 2014 @11:30AM (#47135829)

        Seriously, cobblestone?

        I'm a transportation engineer (I'm posting this anonymously so the details of my employment are not associated to my account) though with very little experience designing pavements. What my experience tells me though is that regardless of the panel itself it needs some sort of frame to hold it down.

        Vehicles generate thousands of pounds of force parallel to the pavement face when they brake. This is what causes rippling in pavement at intersections when the asphalt is too soft or weak. So they've got the friction to stop the car what transfers that force to the ground (and prevents the ground from shifting)? Naturally you are going to need some sort of frame with very positive connection to the ground. That sounds unbelievably expensive. Current roadway costs are near $2 million dollars per lane mile (a 12 wide width of pavement 1 mile long). The materials that make up the roadway are generally pretty cheap (various engineered sands and gravels) and are applied to the roadway using large heavy equipment with very little human labor. You've now replaced that with presumably the same base system (you still have the same loads) a metal frame to hold the panel in place and the panel (these systems would replace the hard surface ie the asphalt or concrete). Even a minimal frame material wise is going to massively expensive. Steel is very very expensive in rough bar form (in comparison to things like concrete and asphalt), let alone in machined frames that require manual hand labor to install. What happens when a frame is bent? How's it anchored? Even massively damaged pavements are usually traversable, a missing or damaged panel sounds like a 2' circumference 1' deep pothole that will rip a tire off a vehicle at speed.

        The next question is durability. They say they've tested them with truck loads, have they done the standard AASHTO pavement test that involves driving a semi around (in a 1/4 mile loop track) on them for 5 years straight to demonstrate long term durability? What about studded snow tires? What about an accident where a car flips at 70 mph and imparts forces that literally pulverize concrete to powder? What if the car then burns (a typical car fire approaches 3000 degrees) What about an accident where hazardous or corrosive products are spilled? What happens when a car being chased by the cops has it's tires shredded but then keeps driving on rims for 20 miles until the rims literally weld themselves to the rotor (the typical result on standard pavement is about a half inch groove from every rim for the length the car ran without rubber)? What about road debris coming off cars and hitting other cars (I've seen sections of concrete a foot thick destroyed by heavy objects falling off semis)?

        How long are the panels good for? We design asphalt roads for 20 years and concrete for 40-50 years. And though the asphalt requires perodic treatments as part of it's life cycle unless a mistake was made they generally last that long. Most of the interstates lasted far longer than the 40 years they were designed for, in my state we've still got original interstate in locations that is approaching 60 years old.

        We use the materials we do in roads because they are cheap, easy to put down (ie not labor intensive) and easy to fix (a temporary fix can involve dumping and spreading a load of gravel with common construction equipment). This system just screams money, and labor and lack of durability. Maybe I'll be wrong, I suspect I won't be. The ESALs (equivalent single axle loads) that a pavement takes over a life time can be astonishing (trillions of pounds of force over a 20-40 year lifetime). The panel and frame that support this are going to be flexed billions of times a year, fatigue fractures are a very real concern in metals.

        Anyway, as I say I might end up wrong, i suspect I won't. I'm astonished people donated a million bucks for this and I believe once they do the real AASHTO testing that will be required before this can be used on roads they will demonstrate

        • Some good points, but if you're going to post such a long rebuttal to the concept you should first watch their videos and read their faqs. A lot of these points have been covered, though there are undoubtedly lots of things that need to be tested and the kickstarter is apparently to help them hire those kinds of experts. I heard about these guys some years ago and am delighted they made so much progress, so I'll take a few minutes to reply (since I just read their faq, watched the videos, etc.). p.s. they c

          • by mattr ( 78516 )

            p.s. I would just like to add that there is an awesome story by the great Robert Heinlein, The Roads Must Roll. He predicted moving solar powered roads decades ago. Fiction, but a great story about engineers with a can-do spirit like a lot of his stories. I remember it well from when I was a kid and reread it once in a while. I'd like to recommend it to you. Some ideas are neat but just bad engineering ideas, and some of those become better when you figure out workarounds or the science evolves. Like, I am

        • by F34nor ( 321515 )

          Have you looked into geopolymer concrete? How does a modern freeway compare with a modern airport landing strip?

        • Yeah, they're as loony as the idiots who tried to introduce portable computers.

        • by reg ( 5428 ) <> on Saturday May 31, 2014 @08:24PM (#47138583) Homepage

          As someone with a PhD in Pavement Engineering, and an active researcher into pavement design, let me say this is a classic case of someone thinking that because something looks simple it is. Pavements are the most complex civil engineering structures to design, because they are the only structures designed to fail in fatigue. My wife showed me their video the other day, and all I could do was laugh. Reading their FAQ now, shows they've never asked an actual pavement engineer for their input (and FHWA funding shows nothing, in fact googling shows that they're not even really being funded by the FHWA research budget but by the Small Business Innovation Research (SBIR) program i.e. this is money to promote small business, the research is a secondary goal).

          Just a correction for you though - there is not really an AASHTO testing protocol, that was a one off test done 50s and 60s. Now, most proof testing of these types of innovative designs are done by accelerated pavement testing.

          Before we even look at the engineering, look at the cost: the highest cost pavement currently are precast concrete slabs, which are similar in some ways to this idea (except they are 50 times the size). They cost about $3 million per lane mile to install. There are over 8 million lane miles of public road in the US, so their idea in their video of covering all the roads in the US would only cost $24 trillion (or nearly twice the US annual GDP) assuming they could get the cost down to that of concrete... Assuming for the moment that the solar panels themselves are cost neutral, just the cost of the glass and support structures would make this impossible to afford.

          From an engineering perspective, you have functional and structural criteria. Functional are skid resistance, spray, noise and light reflectivity. The glass would polish, resulting in low skid resistance at high speed, and bad light reflection. Their textured surface would be OK for low speed skid, but really bad for noise and spray, even with drainage between the panels. Many new pavements have a porous top layer for this. Their paving stone like pattern would be really bad for noise (like block paving). Putting LED lights into pressure sensors for animals would be fun, but probably not reliable, and on roads you have to have systems that are reliable because either drivers can trust them, or they are a waste of time.

          Structurally, the fact that they refer to gross vehicle mass is a dead giveaway that they don't know the first thing about pavements... The critical number is wheel load. Their panels look to be an awkward size between an interlocking block paver where the wheel load is spread across several blocks, and a concrete slab. The panels would need to be connected in such a way that they can expand and contract, with sufficient load transfer between panels for the entire surface to act as a continuum. With this size of panel there would a lot of flex at the joints, which would break most materials. Concrete slabs get joined using 1 inch dowel bars... Assuming these were placed on existing pavements, maybe they would work, but my guess is that they would get beat up quickly by highway traffic.

          Then there is a question of life cycle assessment. Their "numbers" page shows they also know nothing about this either. They just include the benefits... There is no measure of the system, including manufacture, construction, maintenance, etc. They also don't have albedo measurements, etc...

          So, to conclude, I don't think this idea is going anywhere fast. Their first step should be to hire a pavement engineer. Then they need to do some lab testing, then use their $1.7 million for an accelerated pavement test to determine if their design can work as a road, before they do any more messing around with electronics... At least their idea is not as silly as the people who want to put piezoelectric generators into pavements to capture all the "wasted" energy...


      • The thing is that it is not snowing most of the time so you only need the heat for brief periods of time. The road can soak up the solar power over many days (where individually each day could not provided the power) and dump it's power over a short period of time to heat the road to melt the snow.

    • They want to have plenty of those road, so it could be imagined that roads in an area would melt the snow using energy collected by roads where the weather is better.
      • Even if we're talking about using solar power from tiles in Texas to melt the snow covering tiles in Vermont, we're talking about moving gigawatts+ of power here. I don't think these tiles could replace the huge power transmission lines.

    • Solar powered melting devices have two advantages over blacktop from a thermodynamic perspective:
      - Blacktop conducts part of the collected heat into the ground, whereas solar collection could hypothetically collect the energy before it gets to the ground, leaving more available to radiate back upward.
      - When it isn't snowing, blacktop still radiates into the air above it. These devices could store energy to be released only when it's actually snowing.

      That said, implementing these devices as anything other th

      • essentially combines the labor-intensiveness of a cobblestone road with the specialized labor requirements of a hardwood floor

        IF ONLY!

        The plan is to have large concrete access channels []underneath the hexes.
        Big enough for a man (or a wild dog, or a bear, or a nest of snakes, or wasps...) to crawl through.

        Cobblestone roads?
        These are concrete crawlspaces filled with easily harvestable copper and covered with electronics with built-in heating elements.

        You know how roads tend not to spontaneously catch fire then burn for miles underground and you can't put them out with water cause they are electrified?
        Well if this ever makes it off th

      • by Livius ( 318358 )

        a billionaire's ruinously expensive driveway

        I think you've found the real use case.

    • From the Solar Roadways FAQ:

      We designed our prototype to use 'virtual storage', meaning that any excess energy is placed back to the grid during daylight hours and then can be drawn back out of the grid at night. This is important as solar energy is only available during the day, but our heating elements need to have power at night in the wintertime in northern climates for snowy weather. However, we can add any current or future energy storage devices to our system. For instance, batteries and flywheels can be placed in the Cable Corridor for easy access, if customers wish to incorporate them. We chose to not use batteries in our prototype system. We fear that, if we make that the norm, our environmental project could leave mountains of lead acid battery in its wake."

      Because solar roads will be on the electrical grid as both producers and consumers, the net effect is that roads and parking lots that aren't under snow cover, (because they've been plowed already, or because they're in a snowless region), provide power to offset that used to melt snow on roads that do have snow falling on them. Yes, this means that the snow melting capability will only be significant when the total road surface area 'paved' with these cells reaches a certain cri

    • by AmiMoJo ( 196126 ) *

      Their FAQ addresses this specific point. The heaters are powered by the grid, not solar alone. The solar panels feed in to the grid and then draw back out from it at night out when heating is required, eliminating the need for batteries.

    • I don't think the plan is to melt snow from the energy generated from the panels but would require an input of energy. Obviously there are few things more effective in turning incident solar energy into heat than black rough surfaced asphalt.

      Imagine the opacity of the glass surface after a few days of traffic with steel studs or rocks caught in the treads or just tires driving over blown dirt and dust .

      The idea of a solar roadway sounds great to the intuitive but lousy to the analytical and practical.

    • where to start with this...

      This approach has several problems. Firstly, the solar cells / heater mechanism is less energy efficient than a black road surface.

      [citation needed]. you sound like a wikipeida editor.

      Secondly, if the snow falls when it is dark, the solar cell will stop working (unless it has some big batteries are present, and even they won't last long in a heavy snow fall.)

      [citation needed] or are you also a meteorological modeling scientist as well??

      Lastly, the best sun occurs in the summer, and the snow hits in the winter, when less solar energy is available.

      [citation needed]ahh, you're a nobel winning physics scientist as well. then you are an expert in all things and don't need to provide any citation!

      About the only way a solar cell can keep up with incoming snow is if the solar array is much larger than the area of snow being melted. However, even then, you still have the problem of the solar array getting covered in snow ...

      not if the solar panels were kept vertical... which would reduce the angle of incidence to snowfall.

      • I have a hard time taking anybody serious who thinks you need to be a meteorological modeling scientist to know that solar panels don't work when it's dark...

  • by De Lemming ( 227104 ) on Saturday May 31, 2014 @09:48AM (#47135359) Homepage

    The Verge had a good article criticizing this project []. The article doesn't break down the project completely, but points out why their goals are far-fetched, and people should not get too exited.

    Also note that when looking at the project, it's not initially clear that a connection with the main electricity grid is still necessary. At night, displaying the signs and defrosting the road is done with electricity from the net. During the day, the solar panels can transfer electricity back to the grid. Their current implementation doesn't include batteries to store electricity locally, and this wouldn't be very environmentally friendly anyway.

  • Honestly this seems too good to be true. I see this endeavour never making it past a trial phase as per the below:

    Disclaimer: I haven't done too much research on the subject past viewing that video that went viral a week ago.

    1) Capital Cost: Looks expensive. Think of all the trenching/corridors that would need to be built. Never mind the electrical infrastructure which I think would need to be upgraded. The incremental cost to add all this to existing and even new road development is intuitively high. Espec

    • It seems by approaching an optimistic (hopeful) and uneducated public they found a million dollars worth of sucker money

      That's a BINGO!

      Someone needs to take steps to save the planet.

      HAD they made this to be installable as easily as a macadam road, and as robust and scalable, there is a VERY slight chance that somewhere down the very long road this would actually benefit the environment.
      Mainly because something like that is pure science fiction.

      Instead, they made this in such a way that it must sit on a HUGE foundation of concrete, with both access shafts along the whole thing AND storm-drain channels (storm-water is apparently a pollutant according to their video) AND ev

      • by F34nor ( 321515 )

        Storm water is a pollutant depending on what it is flowing over or leaching through. In addition it can overflow combined sewer storm water systems and dump untreated waste into rivers. Have you ever done any storm water work? What county do you live in? Go try and get a permit for an acre of flat impervious surface and find out.

        Not all concrete leaches C02. Make it out of geopolyer concrete a C02 sink closely related to the long carbon cycle.

        If you have to invest some energy to raise the surface temp to ju

  • Test it parking lots first as some real year round traffic and weather will show where things like this will fail.

    • Test it parking lots first as some real year round traffic and weather will show where things like this will fail.

      That don't make no sense, because what you want is to have it in the actual use case scenario for testing. On a nice straight piece of road someplace, where people don't tailgate too much, ha ha. You need vehicles to be going over it at speed, and you need significant sections with on and off transitions etc so that you can perform a meaningful evaluation.

      As slippery as oily, wet pavement is, I don't see how glass can't be a zillion times worse, no matter how you texture it.

  • How much are these going to add to the light pollution problem? Lights pointing straight up are not what we are looking for.
    • by Hydian ( 904114 )

      Hmmm...Good point...but if they can make it smart enough to detect animals on the road and warn drivers, then they could design them to only light up the sections of roadway that are in use, which would presumably make them even more energy efficient. Side effects of this methodology would be that it would alert cross traffic that vehicles were coming and it could dovetail into smart intersections, autonomous cars and traffic flow, but that is jumping a few steps further ahead into that general direction t

    • Very little.

      They will fail long before that.

      It costs far more than ANY form of road (except maybe suspension bridges) and it is far harder to maintain WHILE it is far less durable.
      And on top of that the quantity of electricity it produces is negligible.

  • The Feds won't fund a national MagLev.

    One is feasible and lowers carbon footprint.

    The other is too costly and uses enormous amounts plastics.
  • by crow ( 16139 ) on Saturday May 31, 2014 @12:20PM (#47136071) Homepage Journal

    The should do the simple tests first.

    They claim that the glass cover panels can hold up to traffic and provide sufficient traction. Why not mount just the glass covers over a stretch of road and see how it behaves? Until they get the covers right, the rest is irrelevant.

    Once they have the ability to make a glass roadway, then they can deal with the question of what to put under it. How about just LEDs for traffic marking? Will they work in the day time? Will they put out too much light pollution?

    Once they have the traffic markings working, they can get the heating elements needed for installing where it might snow. I'm under the impression that they have to melt the snow because the panels won't stand up to snow plows. Maybe it will make more sense to run pipes with heated antifreeze solution instead of direct electric heat. Maybe it will make more sense to redesign the glass covers to stand up to snow plows.

    Once those are solved, putting in solar panels is a no-brainer that helps the economics of the project work.

    In the end, once all the technical issues are solved, it's a matter of economics. What is the cost of a road made with the panels over 50 years as opposed to a traditional asphalt or concrete road when all the maintenance is factored in for each road type?

    Considering all the above, I'm convinced that it makes much more sense to put solar on rooftops.

    • One economic test would be to compare the price of installing the solar roadway with the cost of building a cover over the roadway with solar panels on it.

  • I would rather see more businesses and individuals install PV into their local locations, that are either grid-tied with failover to standalone when there is a grid power outage, or standalone.

    No need for solar roads, when most people and businesses have plenty of square meters on their property that could have PV. Over roofs, over driveways, over parking lots, and such.

    • by laffer1 ( 701823 )

      Then we need some changes in thinking on the legal side. Laws to allow individuals and businesses to install solar panels despite HOA or downtown "beatification" laws. I'd have solar panels on my house right now if I could.

  • I was curious so I added up all the crowd funding levels for this project. I came up with some interesting numbers.
    1. The sum of all funding levels is $1.37M and not $1.75M. Where does the other $400K come from?
    2. 80% of the contributors gave $50 or less resulting in 35% of the contributions.
    3. 1.2% of the contributors gave $300 or more resulting in 22% of the contributions.

    I wonder how many of those big contributors have a stake in the business and want to make it look good.

  • Roads are not flat []. I realize that is an extreme example but roads are not always completely flat. They go over hills, through valleys and weather causes them to buckle slightly. All that has to happen is for an edge of one of these panels to come up a bit and you get a permanent bump in the road. Conventional roads can handle this as the bump just wears or is ground down and the road is fine again. With these panels any protruding edges would receive stresses at different angles and be prone to breakage. T

  • by Briareos ( 21163 ) on Saturday May 31, 2014 @07:21PM (#47138357)

    Thunderf00t [] summed up a lot of arguments why this is futile and/or a scam in this video []. From the summary:

    Solar FREAKIN roadways is a nice idea, but then again is a pogostick that can hop to the moon as a cheap, reusable trans-orbital vehicle.

    Is it plausible though. Well it basically proposes the union of 3 or 4 technologies. LED lights, solar panels, and glass roads.

    Glass really isn't a feasible material to make roads out of.

    1) its too expensive. Just coating the US road system with roads would cost many times the federal budget.
    2) Its too soft. Even with a textured surface for traction, it will wear away too quickly. Dirt on roads is basically small rocks, which are generally much harder than glass. Imagine taking a handful of dirt and rubbing it [on] a window. Now imagine doing that with the wheels of a 20 ton tractor/trailer.
    3) I have doubts about the physical properties of the glass to take the load and mechanical heat stress required of a road making material.

    Solar panels under the road is a bad idea from the start. If they are under the roads, they are hard to maintain. They will have reduced light from parked cars etc. They are fragile. Not really congenial to the conditions you are likely to get on a road. In many ways building a shed over the road, or just having solar panels by the side of the road is a far better idea. However the power transport really isnt practical. One of the most efficient ways to transport electricity around is as high voltage AC. However to build those lines would probably double the cost of any construction. To bury the cables is even more expensive.

    LEDs for variable road marking have been partially implemented. They are usually only cost effective in dynamic traffic management systems. For most roads its utterly pointless as the road markings almost never need to be altered. These LED are usually not easy to see (especially in full daylight when the solar panels are meant to be generating power).

    However solar powered roadways has generated well over a million dollars for Julie and Scott Brusaw (a therapist and an engineer).

    I'm still on the fence as to if they are just delusional dreamers or (now millionaire) con artists. A lot of this looks like just direct 'what if' daydreaming, but then you get the part of the promotional video where they are shoveling ground up coloured glass into a wheelbarrow, while narrating that they use as many recycled materials as possible in this project. It's very difficult to not see that as a direct lie. They must know full well that they did not use any of that material in the construction of their glass tiles.

    (And yes, he's got a PhD in chemistry, so I trust he might have more of a clue or two what happens when a truck hits the road than an electrical engineer(!)...)

To do two things at once is to do neither. -- Publilius Syrus