

Why Solar (Freakin) Roadways will never exist - richbradshaw
https://www.youtube.com/watch?v=H901KdXgHs4

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psgbg
I was really excited by the idea. At least it was interesting.

When I first saw the video Freakin Solar Roadways... I came across with the
first problem. The solar panels produce DC... which it's really bad for
transport energy, then you could transform it to high voltage AC. So I'm ok
with it but then you will need wires and wires. So immediately I supposed that
it won't scale to a Roadway system.

So in a second thought probably it will work for sidewalks and parking lots
and maybe if you could storage the power then use for street lighting. At this
point for me this idea will work in the cities only. But then put solar panels
in buildings sounds more cost/effective (and way more efficient). So I wasn't
sure anymore at this point.

The video pointed to me some other flaws. And now meh.

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zoowar
I think we need to distinguish the road technology from the solar technology.
Is this a viable road technology when decoupled from the solar technology? Is
this mechanism of solar collection/distribution more or less effective than
other efforts? Clearly, our paved-over world could be put to better use, but
is this approach a net gain or is it just solar buzz?

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psgbg
About the collection. In general the photovoltaic technology efficiency is
about 17%, commercially it's about 27% and there's technology reaching up to
45% but not commercially available.

There's another problem, the efficiency drops with temperature. I don't know
what kind of heat dissipation this technology is capable of but assuming the
worst case scenario the solar panels will surpass boiling point temperature.
This means that without cooling the system in the solar peak it will have the
worst efficiency by a huge margin. A typical solar panel is cooled by air,
this possibly is siting in a heat insulator.

Another problem are the scratches. Ideally the glass need to be clear, but
over time it will lose it's transparency so there is another mayor drop in the
production.

There's another problem. As you can see in the video, using these roads you
need to transport energy in or out. For do that you need wires, many, but they
are expensive. Consider you don't use the energy generation... you still need
wires to use the leds.

I consider more intelligent put photovoltaic cells in every building in the
city. As you use the same power infrastructure you don't need to worry to
install new wires. As the cities concentrate the use of energy then the lose
of power due to heat (Joule Law) it's reduced. It's a plus in efficiency. As
daily beings even if we don't save the energy collected (because batteries are
expensive) is a win. We could use other energy sources during the night.
There's another possibility, some scientist are trying to create a
photovoltaic paint, this will be even more cheap but also less efficient.

Another ideas. Use the heat produced in thermal plants (Gas/carbon/Dissel).
For example to heat the roadways or houses in cold areas (you will heat you
house anyway). Use the heat for industries: smelters, oil refineries, glass
makers among other. Remember the heat is a waste anyway, but is useful in many
industries.

Use the sewer waste to produce biomass energy. Think about it, if your feces
produce methane in your body before you poop... The idea is, in general the
energy we use is carbon buried eons ago. Methane does not add carbon the the
atmosphere only use carbon already there. Then add the previous idea and...
imagine how much petroleum you can cut with this.

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richbradshaw
This project is in my view a really good case study on how if you have a cool
idea, and can back that up with some really good points (recyclable, tron,
green), that you can convince many people that it's a great idea, without
actually delivering anything that can be created.

