Why Solar (Freakin) Roadways will never exist | Hacker News Reader

Why Solar (Freakin) Roadways will never exist

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4 pointsrichbradshaw4 comments

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.

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?

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.

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.

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