Solar “Freakin” Bullshit

If you are on Facebook, Twitter, or any other social media network, chances are you have already heard of this project – (I obviously do not endorse it). 20140429030846-LEDs_-_white If you haven’t heard of it – it’s a project that wants to replace the surface of all roadways, sidewalks, parking lots, airport aprons, runways, etc, all with these 7″ hexagons that contain about 50 high powered RGB LEDs to be able to make configurable patterns, photovoltaic cells (solar panels) to power them, heating elements to melt snow, and about 1″ thick of specially textured glass on top. The panels can also communicate with each other wirelessly, presumably as well as with a base station of some sort, through the mesh network.

Sounds cool. Looks cool (*1). Is definitely technically plausible. What’s not to like about it?  

*1: Though if you look at illustrations on that page, you’ll find something strange – those tiles seem to have much higher resolutions than would be possible using just 50 LEDs per panel.

If you actually read through the Indiegogo page, you’ll find that it has no mentioning of cost at all, except that it supposedly “pays for itself” by generating electricity using those solar panels.

Yeah well, if that’s the case, why aren’t all our roofs covered by solar panels already? Solar panels do not pay for themselves at the present time, in most cases (only in places with extremely high sunlight, and very high electricity prices). That’s why.

If you look at the FAQ, there is a question “How much will your panels cost?”, and the answer essentially boils down to “we are not going to tell you”.

They already have working prototypes, and they can’t even give us an estimate of production price? That’s something all engineers are trained to do from very early on. How can you go as far as having working prototypes, and not having even an estimate of production cost? Or maybe they are hiding something?

But fear not, there is enough details on that page that, with the power of back-of-the-envelope calculations and Wolfram Alpha, we can come up with an estimate that should at least be within an order of magnitude of the actual cost –

How much does one panel cost?

A 7″ hexagon has an area of 0.082 m^2


Judging by the picture, and by the fact that they need to be able to support large trucks, the glass should be at least 3/4″ thick. How much does 3/4″ thick glass cost? I checked a few places, like this one, and they are pretty consistent. $21 per sqft, or $226 per sqm. I’m assuming margins are not very high in the glass material business, so let’s say the cost is $150 per sqm? The glass on a panel would cost $12.30, assuming post-processing is free.


Judging by the picture above, there are about 50 LEDs on one panel. Since they need to be able to change colors, they need to be RGB LEDs. Since they need to be visible under direct sunlight, through 3/4″ thick of textured glass, they need to be at least 1W, possibly much higher.

1W RGB LEDs cost about $8 each at 5k qty. Let’s say $5 at practically infinite qty? That’s $250 per panel.

Solar Panel

How much do solar panels cost?

The best solar panels available right now are about 20% efficient, and 1 m^2 gets about 1KW of sunlight on average, when the sun is directly above, with no clouds.

So with a 7″ hexagonal tile, we’d be looking at about 16.4W per tile.

Actual average power output will be 5W or so since it won’t be noon 24/7, but we still need to get 16.4W panels to get 16.4W when it is noon.

Before we go into price… did you notice something doesn’t add up? How the @#$@#% are we going to power 50W worth of LEDs with just 5W average?

Ignoring that for a second, the current cost of solar panels is about $0.70/W. That’s $11.48 per tile. Not quite as bad as I had imagined!


This is harder to estimate, but the wireless module will cost at least $5 at qty, and the CPU $2, and there will also need to be at least 3 MOSFETs per LED at maybe 3 cents each, for a total of ~$5.

I’m going to estimate $20 in electronics per tile. Unfortunately I cannot really justify this estimate further, but I believe it’s a very conservative estimate.

I am not going to include the cost of a 50W power supply… because we still don’t know where that power is coming from.

Total cost

Taking into account those components above, we are looking at a total of $294 per tile, most of which is from the high powered LEDs. The cost of the solar panels turned out to be almost negligible.

How many panels do we need?

First of all, what’s the total length of roads in the US?

6.5 million km in 2007.

Or just over 2 million km if we only count motorways (freeways), highways, and secondary roads (secondary roads are main roads in cities that feed into the highways). Let’s use this number, since it’s smaller.

How wide are the roads? According to the US Standards for Interstate Highways, the minimum lane width for a highway is 3.7m. Or 7.4m both ways. That’s the absolute minimum, and doesn’t include sidewalks. So let’s say the average width of roads is 10m, as a conservative estimate.

How much road surface is that?

2e10 FREAKIN m^2

How many tiles do we need?

2.44e11 FREAKIN tiles


But how much will that cost?

71 trillion dollars.

Note that the cost is almost entirely proportional to area, so changing the tile size won’t change that number significantly.

Since we usually have trouble taking astronomical numbers like that in perspective, let’s compare it to a few other astronomical numbers –

The entire annual US military budget is 0.683 trillion (it’s already the highest of the entire world), which is about 4% of the US annual GDP of 16 trillion.

That means, if we increase taxes to 100%, and shut down education, medicare, the military, and all the other government services, we will be able to make all our roads (well, just the big roads) shiny in 4.5 years… assuming we can still maintain a $16T GDP in those conditions.

Cost of labour, transportation, and disposal not included. They say they are aiming for 20 years life time for those tiles. That’s funding-seeking-speak, so let’s say 15 years as a more realistic estimate.

That’s still $4.7T/year, or almost 7x the military budget.

Even if I am off by an order of magnitude, that’s still 470B/year.

What else is wrong about this project?

Many things, in fact.

I’m not going to get into all of them, since I don’t have all day, but here are few of the best –

Charging EVs with solar panels

Inductive charging is 60% efficient over a gap of 12 cm, and decreases rapidly as the gap increases. Most EVs sit more than 12 cm from the ground. Even if one EV can draw power from 50 tiles, that’s 250W total, and about 125W after inductive loss.

A Tesla Model S base model has a 60kWh battery. That’s almost 21 days to charge at 125W. In those 21 days you can drive 230 miles.

More realistically, if you use it as an extra/bonus thing, if you drive for 4 hours on those tiles, you would have charged your battery 0.7%.

It will cost the same as paving


Sure, you can sell the electricity, if you don’t even need 5W to run a tile. How much can you sell it for?

Assuming a 17c/kWh buyback price (that’s the current solar buyback price in Georgia, and will likely decrease significantly if supply increases significantly), over 15 years, you would be able to sell 5W for $111, likely much much less if all the roads suddenly start selling back power, and government can no longer afford to heavily subsidize selling back solar power (or if the government own those tiles).

Why include solar panels on those tiles?

Why not just put them aside, or get rid of them completely since most of the power is going to have to come from the grid anyways?

The problem with solar power is not space, otherwise all our roofs will be covered by solar panels already.

Putting them in road tiles is solving the wrong problem.

Why not just build solar power plants elsewhere (in a desert), centrally? That would be much more efficient, and with HV power transmission, there is actually not much losses.

We don’t have many solar power plants in use today, mostly because they are still cost prohibitive.

Putting them in road tiles below 3/4″ of glass won’t magically make them any more efficient… quite the opposite in fact.

Of course, the real reason they are doing this is because people have warm and fuzzy feeling about solar power, and we WANT to be convinced that there is a way to use it cost effectively, and we are willing to turn off our common sense for a little while to get that feeling.

How do I identify nonsense like this in the future?

When you see a Kickstarter or Indiegogo campaign that is as technical as this one, yet doesn’t mention any numbers, and gives you everything in qualitative terms, you should be wary.

Just because the tiles cost money and you can sell electricity for money, doesn’t mean the amounts are equal, or even comparable in order of magnitude.

Just because you can theoretically charge EVs through induction, doesn’t mean you’ll actually be able to charge them at a non-negligible rate, and be worth the added cost.

It’s all in the numbers.

Just because 500 media outlets reported on it, doesn’t mean they have actually gone through it with common sense and a little bit of scientific literacy.

I suspect even the scientifically literate among the journalists actually intentionally turned a blind eye to the obvious infeasibility of this idea just so they can write an article and get viewers excited.


49 thoughts on “Solar “Freakin” Bullshit”

  1. Totally right on the feasablity of this project on a large scale, but you say some things that don’t take into account a number of issues. I (and most in power, I expect) would be against the immediate large-scale implementation of this technology as it is, but that does not mean that it doesn’t deserve funding or attention.

    “The problem with solar power is not space, otherwise all our roofs will be covered by solar panels already.”

    Well, no… there are many factors at play here, mainly the state of the technology at this state of development. The reason that solar technology is as inefficient and costly as it is is because the government hasn’t been investing in solutions like it. Like any technology, efficiency will go up and production costs will go down amazingly once it begins getting some funding and forward motion (just look at the calculator, smartphone or computer). In this day and age it is the responsibility of the government to invest in initiatives like this for their potential in advancing our methods of gathering power. It just takes citizens and those in power to commit to forward-thinking initiatives that are less short-sighted than the next term in office.
    If solar panels don’t pay for themselves (a disputable claim in itself) then all it would take is some investment from governments to help develop this technology (a much better direction than Big Oil partnerships and tax cuts, in my opinion!)
    Sure, installing this stage of panel on every square foot of America is super costly and probably a bad idea, but I don’t think that that’s what anyone had in mind. Although they used this as a selling point in their videos, it was more of an illustration to show the vast amounts of paved space in America. Pavement is super bad for absorbing heat in cities and contributes to significant amounts of more energy being used in cooling, so even the fact that solar panels are NOT pavement is a huge improvement. I’d like to see some specs on the panels’ heat absorption/reflection to be more informed on this front.
    Projects like this are embryonic, but will evolve and become greater than we can imagine if given the backing. Some more insightful reporting would be great, but the fact that this project has gone viral is a wonderful thing. It gets people thinking about sustainable possibilities for the future, which is the first step in making large-scale systemic change and holding governments accountable towards larger climate issues.

    1. Hi Ben,

      Thanks for weighing in on this issue.

      First of all, I do totally agree that the government should invest in research into sustainable power sources (which include solar, but also things like less environmentally-disruptive hydro power, geothermal, wind, etc).

      What I did not agree with, is this project and their use of deception (they are either highly delusional or deceptive, and I’m inclined to believe the latter, since they are technically competent enough to build prototypes) to get funding to allegedly put into production something that is clearly not ready and is laughable on many technical fronts.

      Note that on the Indiegogo page, they clearly said that the technology is ready, and the funding will be used to put it into production in the short term.

      I am glad that the government is not funding this into production, which probably explains why they are on Indiegogo now.

      They have already raised $1.2M, and that money is not going into solar panel research. If he uses it the way he claims he will, the money will just be paid to engineers to prove that this concept is totally not feasible, and the $1.2M will vanish just like that (hiring 10 engineers for 1 year? that’s more than $1.2M in salary).

      If people really cared about solar research, their $1.2M could have made a much bigger difference if donated to for example labs that are actually involved in developing solar cells, instead of this campaign that won’t be going anywhere for the obvious reasons pointed out in this post.

      As for putting solar panels in road tiles – there are much cheaper ways to make roads reflective. For example, by painting them white, covering them with some sort of metal, or even covering them with mirrors, all of which are much cheaper than using solar panels as very expensive mirrors. Then we can put solar panels in deserts, where they are much more efficient than under 3/4″ thick textured glass.

      It’s true that it’s nice solar power is gaining all the public attention, but I would have preferred it to be done in a way that is not so deceitful, and not through irresponsible and provocative marketing and reporting.

      Totally unrelated, but on cost-effectiveness of solar power in current state –
      The only way I’ve seen solar panels pay for themselves is through heavy government subsidy. That is obviously not economically sustainable, and will not scale. If everyone suddenly decides to get solar panels, and the government still subsidizes them at the current rate, the government will be going bankrupt very soon.

      In a way, government subsidy is another way of funding solar panel research, by artificially making them more attractive, and hence create a higher demand for them.

      Also, most of the calculations that show solar panels to be cost-effective assume a certain rate of electricity cost increase in the next decade or 2, when there is no evidence that it has started happening, and is based on the assumption that no other sustainable energy development efforts will be fruitful, and be able to provide cheap power in the future.

      Most of them also don’t take into account compound interest (average rate of return on investments is 5-7%, so $10K now will be worth almost $20K in 10 years).

      For example, say if you have to pay $20K to get a system installed, and it has a life of 20 years, and will give you $1K a year. On the surface it looks like you are breaking even, but the truth is far from it. If you held on to the $20K, it would have become $64K at an annual rate of return of 6% (which is typical).

      1. Thanks for the prompt and thought-out response! I appreciate it and it helps inform me a lot more. Issues like these are always so multifaceted and it’s important to have critiques on all fronts.
        You’ve talked about solar panels in the desert – are there any other good routes for solar (perhaps in less arid environments) that you think would be feasible, or do you think it’s not yet developed to the point that it should be implemented on a large scale?

        1. Unfortunately I don’t really know much about solar panels :(. I have used them in a few projects so I know how they work electrically, but I am not really following the research right now.

          1. I agree with a lot of your comments in principal but solar is exceedingly more feasible than your comments indicate. Obviously not everywhere in the country, if electricity is under 10 cents a kilowatt hour on average, they aren’t going to be of much benefit but there places with significantly higher costs of power where you’re looking at a return in under 5 or 6 years.

            With a lifespan of 35+ years on most panels out there today, you’re certainly looking at a long-term energy production investment but you could line solar panels all the way from the California coast to Maine and you’d still have the one inescapable problem to deal with……where does all this power go when it is produced?

            The highest demand levels are often in the early evenings when solar isn’t producing much, if anything at that time. For it to become truly viable, there needs to be an affordable and efficient storage solution that allows this power to be retained long term. Until that happens, it will be more of a “feel good” gimmick than anything else.

            Even in solar obsessed Germany they’ve been turning to coal to replace their nuclear plants because they recognize that while solar and wind are super awesome and cool, people don’t tend to enjoy their power going on and off every 10 minutes or so.

            1. That is entirely possible. I haven’t looked into home solar panels much lately, so things could have changed.

              Energy storage is definitely a big problem. Modern battery technologies are not cheap enough yet to effectively power the entire country for a few hours.

        2. The reason to put them in the desert is because A) the closer to the equator you get, the less atmosphere you have to go through and hence the more energy actually delivered to the solar cells and B) deserts generally don’t have much cloud cover (which again reduces the amount of solar energy falling on the panel).

          The above facts are just that, facts. It doesn’t matter if you are using solar thermal vs solar PV, or silicon vs III-V or thin-film vs monocrystalline. The Nevada or Arizona desert is probably the ideal place to locate a solar generating facility in the US, all other things being equal you will always get the biggest bang for your buck there.

          And Matthew is fundamentally correct, a bad idea doesn’t somehow miraculously scale down into a good idea. Matthew also didn’t discuss all the problems with the solar roadways (like the fact that the lighting likely consumes more power than it produces, and the heating definitely does, as they’ve admitted to that). Which means that the payback period will be far worse than you might assume by simply looking at the amount of power the cell produces under ideal circumstances and its cost.

          However, it is an excellent cost analysis. Thanks for the good work, I wish more people would read this and not simply dismiss as someone who is resisting disruptive technology which is going to make the world a better place.

          1. Thanks!

            Yeah it’s very annoying that people would dismiss constructive criticism just because an idea sounds cool and impressive.

    2. “The reason that solar technology is as inefficient and costly as it is is because the government hasn’t been investing in solutions like it.”

      Globally there has been insane amounts of money spent on solar research. Germany has spent on a ton on research and incentives to get people to install solar but even they’ve gone back to coal because the lack of existing storage technology makes solar unable to support the electric grid by itself.

      That is the issue everyone is fighting to solve and there is no shortage of funding for that. The U.S. government has actually been fairly measured when it comes to renewables. They haven’t overdone it and spiked their program the way Spain did, they’ve offered balance tax incentives and grants along with the local states and communities offering incentives for this as well.

      There have been some misfires(Solyndra) but basically the American companies that remain have largely had to learn how to fight and adapt and have grown stronger as a result of it. Meanwhile you look at countries such as Germany and China and as soon as overly generous incentives were pulled, companies who had never learned anything else but to feed at the government trough completely fell apart.

      I think what we have in the U.S. is an organically developed, largely more stable solar industry of battle-tested companies that make some outstanding products.

      In time the storage solution issues will be figured out and use of renewables in this country will only continue to grow further.

    3. I figured I might as well address the efficiency issue. It’s actually very difficult to improve the efficiency of solar cells, and generally speaking, that is a fairly niche research area. The majority of research is how to reduce the price per watt of the cells.

      A friend of mine once told me that his job (head of research at a BP solar cell plant) that his job was basically to make the worst silicon he could so long as it worked, because the less pure, the lower the quality the cheaper it is. If efficiency suffers, oh well… That’s just physical space. Generally money is more at a premium than land area.

      The efficiency problem is complicated. On a semiconductor, electron hole pairs are generated when an adequately energetic photon hits the silicon lattice and the electron drops from the conduction band to the valence bad. So, here’s the problem:

      A single photon either generates an electron/hole pair or it doesn’t. If the photon has adequate energy, there’s a good chance it will, if the photon doesn’t have adequate energy, it won’t. The amount of energy released when the pair is generated is proportional to the amount of energy required (the bandgap). So as you increase the bandgap you get more energy out of each photon (also called an optical phonon), but the lower energy photons (longer wavelengths) won’t generate pairs. As you decrease the bandgap, you get more pairs because a larger percentage of the light generates pairs, but the pairs are less energetic.

      So silicon has a bandgap of 1.1 eV, and that’s what it is. There’s not much you can do to adjust that (at least not economically). There are more exotic materials with customized bandgaps, but they’re dramatically more expensive. Essentially the solar cell is a giant diode, the bottom side is metalized with a thin film of silver and forms one terminal, the top side has fingers metalized onto it to form the other terminal. Those fingers will block light, reducing the efficiency. So less fingers means higher efficiency, EXCEPT that it also pushes current through more volume of silicon (which is fairly resistive — because of traps which are inherently there because you have to dope the silicon to make the diode) and hence your efficiency starts going down as R increases and J (current density) increases) because of the fewer fingers.

      Point being, with current technology, there’s really only so much you can do to boost efficiency. It would take a real revolution in material science to get substantially better efficiency.

      1. Thanks! That’s a nice overview.

        I have learned that in a materials course I took in undergrad, but have forgotten most of the specifics already.

  2. “…Pavement is super bad for absorbing heat in cities and contributes to significant amounts of more energy being used in cooling, so even the fact that solar panels are NOT pavement is a huge improvement. I’d like to see some specs on the panels’ heat absorption/reflection to be more informed on this front. …”

    As an experiment done by yours truly about 3 years ago, I measured the surface temperature on top of a 15 watts photovoltaic panel, after 15 minutes, the surface reached 50 deg. C at around Noon, on a sunny day in August. The bottom was completely exposed to ambiant air (greater than 24″ to the nearest, non-reflective surface), i.e., natural convection, no forced air. I stopped the experiment as I got nervous about somebody spraying nice cool water on my rather hot and dry glass panel… The infrareds out of the thin top surface were really nice as a heat source though the low thermal mass would preempt using them to heat up the night, would thick glass be better?

    This said, in the cities, a reflective surface would not help anything when it comes to energy savings as the HVAC unit of the nearby buildings would have to work overtime, an already observed phenomenom as you already stated.

    We cannot win, could it be because we are not supposed to?

  3. Interesting cost analysis. It was nice of you to comp them the costs of structural elements, conductors & connectors, seals and other basic mechanical parts of the tiles. Also the cost of the prepared road bed and those two concrete channels along each road they’re talking about as well as all the wiring and equipment in them, road surface heating elements, in situ water treatment and probably a bunch of other stuff they’re claiming that I’ve already forgotten.

    There’s non-cost-related issues with this idea too. As just one example, on that indiegogo campaign site scroll down to the images for “small glass hexagon” and “large glass hexagon” and think about driving on a road surface with that texture. At highway speeds. There’s a reason high speed roads aren’t built with interlocking pavers.

    1. There are a lot of costs I didn’t include because I didn’t feel like I could come up with accurate estimates for them, since labour costs, mechanical parts, etc aren’t my specialty (I am an electrical engineer).

      I wanted to make sure my estimate is more or less a lower bound, so I only included things that I am able to accurately estimate, and as it turned out that’s more than enough to put this project into the beyond-moonshot category.

      The 2 concrete channels don’t make a lot of sense, either. They are saying how the tiles can be used to carry information everywhere… well if you just dig 2 concrete channels beside all roads you can do that with regular wiring, too.

      1. I didn’t mean to sound critical, I really did appreciate your analysis. I couldn’t cost out all those other bits either, but I thought they were worth mentioning. Especially since the indiegogo campaign conveniently ignores all of these issues.

        Of course it is worth acknowledging that if someone dredged through the ashes of this project they might find a useful idea or two. Heated runways or lit, reconfigurable parking lots or something. Let’s hope all these people’s money isn’t completely wasted.

        1. I’m hate to burst your bubble, but there really are no new ideas here:

          People have used radiant heating for exactly this purpose for a long time, its just REALLY expensive because its an energy hog (probably why they admit they are only producing half the energy required to keep the tile clear even under optimal conditions).

          As for lit roadways… Well, many airports have runway lights that can be turn on by radio or in a control tower. This has existed for decades.

          As for reconfigurable roadways… There’s a road near where I live which has multiple lanes and they have traffic lights hung over the road periodically that either are red X or green arrows which allow them to dynamically allocate lanes for one direction versus another depending on traffic conditions. That’s literally technology as old as a stop light.

  4. For what it’s worth, I think its pretty clear that each hexagonal tile contains 50 LEDs. I agree on the cost of the LED (Digikey puts a 1W Cree RGB LED at about 7.40 in 25000 qty), so your $5 is generous. However, I think these tiles are a lot bigger than 7″. I think you probably came up with that number from their $10k reward, but I don’t see that as a tile size.

    If you look at the Phase II prototype, it shows the “parking lot” (i.e. the area next to their shed that they chose despite it being in the shade from the building). The parking lot is allegedly 12×36 feet, and is 5.5 hexagons across. Of course we don’t know exact dimensions, but if a hexagon were 2 feet across, then they are 17″ on a side, not 7″. If the LED density is maintained at what it is, this means a LOT less LEDs than you were calculating, almost by a factor of 6. Of course it means that the resolution of the tile is also much worse (and no where near as good as they show in their artist’s renditions).

    1. That’s interesting. I didn’t really think about tile size too much.

      At 17″ on a side, each tile would have an area of about 0.5 m^2. Then if we have 50 LEDs per tile, we would have 1 LED per 0.01 m^2 (10cm * 10cm).

      That does sound like a more reasonable resolution.

  5. Maybe I’m mistaken, but aren’t you saying that without the LEDs the project becomes quite an interesting one?

    1. Not quite. I’m saying that without the LEDs, the project would just be solar panels on roads, which doesn’t make a lot of sense, since there are many better places to put solar panels.

      1. Saving some thousands sq miles from being covered with solar panels makes a bit of sense (I know, many are talking about rooftops, but even for me, someone without any knowledge in the field, this doesn’t sound like a solution). Same as having one structure to maintain, instead of two (giant ones). Of course, it comes down to “heavy” financial calculations and definitely none of us have the data to do them.

        1. Why doesn’t roof tops sound like a solution to you? It’s free sun-facing surfaces that are currently not being used for the most part.

          Maintaining roads and huge solar farms separately will be much cheaper than maintaining a road made out of solar cells, because the solar cells would have to be covered by thick glass to protect them, which not only costs money in itself, but also makes solar cells much less efficient. It also makes repairs much more difficult, and requires complex wiring to get the power out into the grid.

          Why not just build a huge solar farm in a desert where there is nothing going on, and the land can’t be used for many other things anyways?

          Centralization almost always makes things cheaper (having a huge solar farm instead of millions of solar panels sprinkled all over the country).

          1. Well rooftop solarPV actually has two advantages over solarPV farms (which also have the other advantages you mentioned). One is network costs. In Australia power bills have gone up 500% in the last decade and it’s mostly networks increasing capacity across the network for increase peak demand load, i.e. summer afternoon load on hot days when ACs get switched on. Generally energy demand in Australia has been falling since 2009/10 but with a huge increase in residential AC investment the peak demand was climbing. Rooftop solarPV curtails peak load demand which brings the bills down for all of us because of the Merit Order Effect (see Google). MOE means the wholesale supply bidding doesn’t get to the most extreme levels ($2000/MW) it otherwise might.

            The other good thing about rooftop PV is that it empowers people to have an impact on CC when their governments are in denial and not rushing to the 100% renewables scenario we need inside 10years. (The Carbon budget is all gone already and CC already has dangerous momentum built in to the atmosphere and oceans. See

            [Matthew: I have edited the corrected link into this post]

            1. Rooftop solarPV does have the advantage of needing less network. Do you know what the magnitudes of the relative savings are?

              Also, can the government do it cost-effectively, obvious without government subsidization? It seems like most cost-effectiveness calculations take government subsidization into account.

  6. I agree with your exception to this campaign but found your comment “Solar panels do not pay for themselves at the present time, in most cases (only in places with extremely high sunlight, and very high electricity prices).” to be misinformed.

    Complete systems have payoff periods in my city Melbourne of 3-7 years depending on your power usage (it’s all about behind the meter energy savings since FiTs were killed of to 8¢ per KWh while retail supply is about 28¢/kWh). Embedded energy payback is around a year typically on silicon wafer panels and thin film even less.

    1. This obviously depends on your reference point, but Australia would be what I consider a place with very high electricity prices – the average electricity price in North America is about 1/3 of that. Australia also has a lot of sunshine.

      Also, is that without any government subsidy in any form? Many governments subsidize not only the cost of the panels, but they also subsidize selling power back to the grid (give you a higher price).

      1. USA has high soft costs — it’s well known throughout the industry. The industry is not pushing Governments of various levels to address them. Govt red tape is big. Germany made the system streamlined for accreditation of fixing systems etc to the inspections to the sign-offs. Also you don’t have as many installers around so they are charging premium rates. Once rooftop Solar takes off in USA you’ll see commercial install rates fall. Most governments around the world have incentive schemes to prime the market (a healthy Feed in Tariff seems to work best). In Australia we have small scale renewable energy certificate system federally and FiTs at the state levels (some States have all but killed the FiT though). I’m not sure of the details of USA incentives but they do exist at both levels I think. Probably not as strong as they needed to be to prime the market. It’s not your perceived lack of sun, don’t worry about that.

      2. It’s wrong to say they don’t pay off in US though. Many people are doing it for that reason alone not to save the Climate. And even solarCST is going ahead with PPA on commercial terms in CA and solarCST with storage has a way higher LCOE to date than solarPV. SolarPV is even cheaper than connecting to the (unreliable) grid in India over a few years so I don’t see how it could ‘never pay for itself’ in USA.

        1. Ah I see there’s some misunderstanding here.

          I was talking about whether it will pay for itself without any incentive or subsidization, in the context of this project, since a project this scale obviously cannot rely on incentives.

          I do agree that it will very likely pay for itself with incentives.

  7. Better to spend $1.5m on getting the ‘soft costs’ of Solar systems in the USA down to prices like we have in Australia and Northern Europe i.e. the solarPV revolution kickstarters themselves: Germany.

    Soft costs like certification, approvals, installation, financing are all way too high in USA, you guys are being ripped off and that’s one reason why your buildings aren’t covered in PV, especially down south where it would pay itself off in 3-6 years typically with Australian/European costs.

    1. That’s interesting. Those costs I haven’t really looked into.

      Another reason would probably be that the electricity rates in the US is much lower than that in Australia/Europe. We also don’t get as much sunshine at most places.

      1. In many USA states you get almost double the insolation of Germany and they have more rooftop solarPV installed than any country in the world (including all those southern European countries with properly bubbles that exploded a few years ago).

  8. On their website they say they are working on each panel generating 52 watts, not 5. They’re prototype right now generates 36 watts and that’s just a prototype.

    1. That means the tiles are bigger (please see Dan’s comment above). That doesn’t change the calculations significantly (there would be much less tiles).

      Also, 36W/52W is most likely the peak power (at noon), not average power.

      1. They stated those numbers when it was still winter. They live in Idaho, not California, needless to say it probably won’t the greatest condition when they were reviewing the numbers. Also, 52 watts for the solar, they are planning on adding piezoelectric and thermal electric generators as well into the panels to generate even more power.

        Although it doesn’t change your estimate very much it does mean that they will be getting money back, meaning the initial cost will be covered in some amount by the energy these panels generate.

        Also it means the NFC for electric cars aren’t as useless as this article makes it out to be.

        1. Along with the fact that the LEDs electricity that they use will be covered by the electricity that the panel can produce.

          1. During the day, maybe (assuming the much lower LED density with 50 LEDs per 17″ panels).

            During the night, their claimed solution is “virtual storage” because they don’t want to pay for batteries… too bad “virtual storage” doesn’t actually exist.

            They are basically saying power utility companies will store their energy for them for free. I don’t think utility companies are quite down for that.

            If you have tried selling power back to the grid, you would find that they give you a lot more money early evening (where electricity usage peaks) than during the day. That means the city also needs more electricity at night than during the day. Now why would they take in your power during the day, and give it back to you at night?

        2. I am not talking about winter vs summer, or Idaho vs California. I’m talking about day and nights, which happen no matter where you are.

          I am assuming you are referring to their FAQ entry that says they are using 52W panels. That is the maximum power the panels can generate, and has nothing to do with where they are or what season it is.

          Even when they are at a place where they can actually get 52W (say, middle of Nevada), they can only get that at noon. Average over the day would be more on the order of 25W. That’s about 5x of what I estimated with 1/5 sized panels, which agrees with my calculations.

          It doesn’t change the calculations wrt to charging electric cars. Having panels 5x as big means each car would only be able to draw from 1/5 as many panels. NFC is something entirely different and has nothing to do with EM charging.

          Did they actually mention piezoelectric generation? Piezoelectric generation is even worse than solar, by orders of magnitude. They are only used in places where only a tiny amount of power is needed, and no other energy source is available – for example, cigarette lighters.

          Thermal electric generators are also not a new idea. They are very expensive and have low efficiency.

          I can assure you neither of those 2 things will improve the payback ratio.

          1. See the fact that you can’t even comprehend that days in Idaho are different then days in California and that winter days are different then summer days explains a lot about this article and your general cynical view point of this subject.

            “Even when they are at a place where they can actually get 52W (say, middle of Nevada)” WHAT. I JUST SAID THEY WERE GETTING 52W in Idaho, don’t make it sound like they won’t be able to even in Nevada. Jesh. Maybe I should just leave you people alone in this thread.

            Also, they plan on adding piezoelectric generators for night time, like I said before, how convenient that you completely ignored that part.

            1. “WHAT. I JUST SAID THEY WERE GETTING 52W in Idaho, don’t make it sound like they won’t be able to even in Nevada. Jesh. Maybe I should just leave you people alone in this thread.”
              Yes you did say that, and that’s wrong.

              You may want to read his page again, and maybe read up on how solar panels work.

              “Currently, the full size hexagons are 36-watt solar panels, with 69-percent surface coverage by solar cells. This will become 52-watts when we cover the whole surface when we go into production.”

              It does not mean what you think it means. Using 52W panels does not mean you will be able to get 52W in Idaho. The same panel sold in Nevada would still be a 52W panel. It will still be a 52W panel even at night, when it obviously won’t be producing 52W.

              “Also, they plan on adding piezoelectric generators for night time, like I said before, how convenient that you completely ignored that part.”
              Well, if you actually read my comment above…

              And while you are at it, maybe read the Wikipedia article on piezoelectric generation too, and how the US army showed that they were only able to get 1-2W from continuous shoe impact of a soldier. There is no way a road tile can ever get that kind of vibration in its life time, except in the case of earth quake, in which case power generation is probably the least of your worries.

  9. (first of all, sorry, english is not my first language)
    We’re talking about replacing your current electricity sources. Not a project designed to replace 10%, or 20%, but 100%. This means solar panels on roof tops is not a solution, because they cannot aggregate into a power grid. Plus maintenance would be a nightmare. Ok, solar on roof tops plus solar farms plus solar whatever can be a better solution, but let the numbers decide that.
    Also, for the sake of humanity, let some utopia, let’s say 10%, to add to those numbers. After all, they are not trying to invade Iraq or seize Ukraine.
    I’m not from US, so I’m not sure if I’m right, but I’ve never seen a debate like this becoming as viral as this one did. Pay them 1.5 million for raising some questions. Oil companies will pay ten times more to bury them, if they could. Sometimes they can’t.

    1. No worries, your English is very good :).

      Solar panels on roof tops is not optimal, but is still better than solar panels on roads.

      The challenge with integrating energy sources into the grid is being able to efficiently transfer the energy to where the energy is needed (unless the power is generated where it is needed, like with solar panels on roof tops). Sure, some houses use a lot more energy than others, but still, roof area is much better correlated with energy usage than road area.

      For the most part, the key to efficient power transmission is high voltage (this is in fact probably the biggest advantage of using AC for power transmission instead of DC). All modern power transmission systems first transform generated electricity at low voltage to high voltage, do the long distance transmission, and then transform it back down before it enters homes so no one gets killed.

      If you have a 1000 miles of solar panels connecting 2 cities, how are you going to do that? The power will obviously not be consumed along the highway, so will have to be transmitted to the cities. How many transformers do you need? Every half mile? Even a half mile of transmission at low voltage will eat away most of the power in losses.

      The best solution, if solar power generation of viable, is to build solar farms in the middle of deserts. That way, all the solar panels work at maximum capacity, and since they are so close together, we can just build one large transformer.

      That’s the reason why most/all power generation is centralized – coal power plants, oil power plants, nuclear power plants, etc.

      It doesn’t make sense for each home to have their own mini nuclear reactor, and it doesn’t make sense for each home to have their own mini solar power plant, too, for most of the same reasons.

  10. In all honesty, I am more likely to believe an engineer who has been paid by the federal government for the last 4 years to research and develop this technology and have given his estimates, then an anonymous person who writes an article in a obscure blog about how he thinks that the project will fail, who backs up these beliefs with numbers that speculative and which fit his argument.
    That’s all I’m going to say, each person must decide on their own who to believe, but I hope you do some actual research on the topic first before you go straight to hate mongering.

    1. And I am more likely to believe logic and numbers I compute and can verify myself, than authority.

      Where did he give his estimate of cost? I must have missed that?

      The government paid him to research, which is valid, and the conclusion of that research is that this idea is not practical at this time (or within this decade), so the government decided to not fund this project further, and definitely not into production. If they did, why is he on Indiegogo now?

      Good thing that whether I am anonymous or not or whether my blog is obscure or not does not determine the validity of my claims. Bullshit on CNN is still bullshit.

      But if you are into believing in authority, I am also a professional engineer and have worked on a few government-funded projects. My resume is on my homepage ( for you to review if you so wish.

      I welcome your numbers (accompanied by your methodology in coming up with those numbers in as much detail as I have given in this blog post) to challenge mine.

      As far as I can tell, I have done far more research in this than you have. I looked into this for hours to write this post. Did you research beyond his page?

      1. “The government paid him to research, which is valid, and the conclusion of that research is that this idea is not practical at this time (or within this decade), so the government decided to not fund this project further, and definitely not into production. If they did, why is he on Indiegogo now?”

        Are you serious? Government can’t fund companies into production, they can only fund Research and Development which is exactly what they did.

        “professional engineer and have worked on a few government-funded projects. My resume is on my homepage ( for you to review if you so wish.”

        Now a days seems like EVERYONE on the internet is a engineer or at least that’s what they claim.

        Also I highly doubt you’ve done any research in this at all. You probably have seen 2 video and then complied all this shit to crap all over this. I’ve been following this project for 4 years.

        And it kind of does matter that you are anonymous, because you can make claims that your an engineer and I don’t know that you’re lying or not.

        This whole blog is a complete waste of time.

        1. Thanks!

          I did not know engineers are so well regarded that people are actually pretending to be engineers.

          But I am incredibly honoured that you think so highly of our profession.

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