OK, I can't help myself...
The earlier video did a good job of busting the idea of using panels to melt snow, but they used big, country-wide numbers, and I think that loses perspective. So let's break it down for a one mile stretch of road, a 12' wide lane, per inch of snow. And don't forget,
the electricity for this comes from the grid, the panels are covered with snow!
The math conveniently breaks down to 5,280 feet (one mile) times 12 feet wide divided by 1/12 foot deep (one inch) so factors out to 5,280 cubic feet per inch of snow. A cubic foot of snow is typically ~ 15 pounds (water being ~ 62#/cubic foot). So that's 79,200 pounds per inch of snow.
It takes 144 BTUs just to melt a pound of ice. Multiplying and converting BTU to watt/hours, we get...
3,342,747 watt hours per inch of snow per lane/mile. That's 3.343
Mega-Watt Hours or 3,343 Kilo Watt Hours.
That is ~ 3x the average electrical consumption of a US household for an entire month, around the clock! For one lane of a one mile stretch of road!
And of course, some heat will be lost to the ground and the air, but I'll be kind and ignore that for now.
At the approximate national average of $0.10/KWh that would be ~ $334 to melt one inch of snow per lane per mile, or about $1000 for a 3" snow!
A snow plow might get 5 mpg, so that's about ~ $1 of fuel per mile? Throw in a couple bucks for the truck amortization ($250,000, useful life of 250,000 miles - roughly?), and a few more bucks per mile for the driver? And let's assume they make 3 passes to clear 3" of snow (generous?) - so, maybe ~ $18/mile for a 3" snow?
Compared to $1,000
And actually much more if you factor in losses to ambient air/ground.
And those of us who actually live in snow country know what happens when snow melts, and then freezes (when the heaters would be turned off). Black Ice!!!! You need to make sure you get rid of any standing water. It would probably take lots of heat to actually evaporate much of that water.
But the people who are promoting this say it is cost effective, so I guess it must be. Right?
Wrong!
Oh, I almost forgot - power outage during a snow-storm? Ever heard of those? I have!
So now we have a community with these fancy, high tech roads, and not enough snow plow equipment to clear them, and a city-wide black out, and no power from these snow covered panels. Sounds like the plot of one of those B-Grade horror flicks!
Snow-mageddon !
OK, bring it on - what are the non-speculative (OK, I'll give you a break, you can speculate a little) possible benefits that could outweigh the negatives?
-ERD50