ET3D: He has some good points but it angers me that he tells them to be honest and call it "fund my hobby". That's just mean and obviously wrong. That guy have probably never tried doing any meaningful project in his life, so he won't understand it. It's fine to call them naive, but I'm sure they really believe in this project and its ability to make a change in the world.
That's a good catch. I don't think the developer merits unkind criticism.
He and his wife are flippin' cool just for trying, dammit. Some of the critical comments beneath that article are better expressed.
Still, I reckon the actual engineering analysis the developer offers is poor, he makes very bold claims, and almost always discusses only a small portion of the problem faced.
He'll offer a sentence about surface friction and stopping distance, without any figures, and call that solved. (We sent it out to a lab and they said we broke the machine, that's how awesome our road is!) There is no mention of road wear and how that stopping distance my degrade over time.
He states that the road can readily support a 125 ton truck, but makes no comment about a 125 ton truck coming to an emergency stop, which is an obvious and much more serious load condition.
I've just found buried in the FAQ that the power-producing area is 69% of the entire hexagon surface. So my earlier estimate of 60kWh per square meter drops to 40kWh. Subtract the snow melt cost of 10kWh per year and we're left with 30kWh. So now it's 5 years to recapture the energy cost of the glass, and again, that estimate is based on cheap glass, not necessarily one that can resist massive stresses. (And I'm unsure what the cost of including the resistive heaters in the glass would be.)
Thanks for bringing this up, Reever. It's fun to consider.