EEVblog #850 – French Wattway Solar Roadways BUSTED

This time it’s France and their governments ludicrous plan to install 1000km of Solar Roadways from French road building giant Colas Wattway.
Dave breaks down yet again why this is pie-in-the-sky folly.
Forum HERE
Also an update on the 12 months test results of the project in the Netherlands.

Rooftop solar panel output data:

Great article on the French plan HERE

Dave’s other videos:
EEVblog #724 – Home Solar Power System Analysis & Update
EEVblog #681 – More Solar Roadways BULLSHIT!
EEVblog #743 – Solar Roadways Test Results

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  1. Thank you Dave for this really usefull debunking. French people on the “Ministère de l’écologie” in France should pay you for this video as you’ve done the job they should have done themself.

  2. 1- the “at best” is one thing. The at worst is different “grime, traffic, breakage, etc”
    But the AT REAL is even worse: transmission losses, conversion losses to grid AC voltage, etc. If they use the power directly, there will be the separate wiring system for using the DC.

    2- life span is about 10 years, compared to 50 to 100 years for a power plant (coal or nuclear) or a hydro dam. So the capital investment, including removal costs, must be discounted over the lifespan of the system.
    The cost per watt NEVER include the cost of capital in these intellectually dishonest advertisements.

    3- the middle lattitude of France is about 45°, so the angle aspect of the ground, not counting non-linear reflectivity, is about only 70% of a properly aligned (perpendicular to the sun) panel. Of course, this is worst the more north you go, and worse in winter, where the cosine of the angle (i.e. the apparent width projection at the given angle) goes down more and more quickly.
    Now, add the aforementionned ignored interface reflectivity, which goes up with angle, and you get even worse. Overall, the integral (i.e. sum total) of angle as a function of seasonal variations, multiplied by the reflectivity losses at each angle, for a whole year is (my hunch, less than 60%) And this is what Dave noted, comparing the “I believe in Santa Clauss” corporate figures with actual comparable (yet inclined) solar panels.
    I noted that Dave compared angled solar panels with flat roadways. I don’t know if flat roadways power output was given for France’s lattitude (solar angle) and a flat horizontal lay-up on the ground, or if they gave the optimal panel power output (they label them as “up to XXX kW” ) Yeah, up to, but only if installed perpendicularly to the sun when the sun is at its highest point in the sky, where it crosses the least amount of absorbing atmosphere.

    Solar panels at
    “A Wattway panel lasts as long as conventional pavement, meaning at
    least 10 years depending on the traffic, which speeds up wear. If the
    section is not heavily trafficked – a stadium parking lot for example –
    then Wattway panels can last roughly 20 years.”

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  4. you have no clue about goverment policy 🙂
    in summary: more work then better 🙂

    BTW: very good video as always

  5. Another French government engineering project. Two words: “Maginot Line”.

  6. Hola por aquí, me gusta este articulo, no suelo comentar en blogs pero en esta ocasion pongo uno! Sigue así, tienes un blog muy bueno.Ver otra web interesante de web automaticas Si quires aprender hacer webs automaticas no lo dudes Un gran cursos el de NOSESEO.cOM

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