June 16, 2009: Kinetic Plates

[Eclipse]

Originally Posted by AdamTheMechE

This is the opposite of green energy. Any energy collected from cars is only as green as the energy used to drive those cars, minus efficiency losses in the plate system. A car's engine is already much less efficient than any source of the electricity through the land line, and adding in another system reduces overall efficiency in a very non-green way.

What this system does do is rob customers of (granted, minute amounts of) fuel energy, so the overall cost of this system considering everybody involved is greater than before. Granted, the shop saves money after 2 years, which is sneaky, but not nearly as sneaky as touting this as a green improvement.

There's no doubt cars are anything but green, but these plates are simply collecting energy that would otherwise be lost anyway. It's the same concept as the backpack that charges your mp3 player or laptop from the bouncing of your motions.

Instead of powering the checkouts from a city generator, it's using the energy from the cars passing by. The compressions from the weight of the car shouldn't be very great, so driving across the plate should not sap any more energy than driving over uneven asphalt -- the same energy lost through everyday regular driving. Instead of losing that bit of energy to earth, some of that energy goes to drive a generator.

It may be true that now car drivers are paying for the energy to power the checkouts, but note that it's not one driver powering them. Tens, if not hundreds, of cars pass over the plates to refuel a day, so that each individual driver probably loses a few dollars of gas energy a year to compressing the plates with the weight of their cars. The loss is almost nil, and cars lose more energy driving over bumpy roads than a flat plate anyway.

This system recycles energy that would otherwise be lost, and is "Greener" in the sense that it uses that energy rather than energy from a municipal power plant.