The cost must be astronomical.
Why?
Because you're paving roads with circuit boards not tarmac/asphalt.
This is kind of obvious.
but should pay for itself in maintenance and energy.
You mean a nation of road of interconnected circuitboards will require less maintenence than a road of hardened bitumen? If they're claiming this it requires massive scrutiny because complex systems require complex repairs. That requires complex tools and complex training for the guy holding hte tools. That means a higher salary for him.
The issue of under road heating is interesting. Because it turns an energy providing product into a road safety product. What if the heating panels fail? What if just one fails, leaving a patch of hard ice in an otherwise unblemished roadway? The supplier will have to guarantee that such a system will work 100% of the time for many years. I really hope they can deliver on that promise.
And if a load of panels do fail, will the local government be able to fall back on snow plows? I imagine a plow could do some real damage to all those ridged tiles.
I hate to be a Debby Downer but this just doesn't float for me. It's trying to fix way too many problems at once.
It
might probably will work for parking lots and schools but not whole motorways.