I don't think this is necessarily a solution to all of our problems, but I definitely agree in that I think its a step in the right direction, which is the most important part to me. I mean, it may not generate enough power to light up a whole city just yet, but we need a starting point. This sort of technology will probably be refined in the future if it works out well enough and seemingly has potential.

And I don't think there is any ultimate form of energy that can be used as our answers to everything just yet, but if we can combine technologies to economize in the meantime, well, what's wrong with that?

Its done with at least a few hybrids I believe and is basically useful only for electric cars. While the two systems don't exactly preclude each other the ramps are meant to be placed where cars would be slowing down anyway so as to not rob the cars of energy it needs to keep moving and cost the driver gas. This is basically reclaiming energy that would be used for breaking. Since regenerative breaking already does that more efficiently and consistently this system would in effect steal energy from any car with regenerative breaks.

This will never even be close to economical on a city sized scale. Further, any money spent trying and inevitably failing is money better spent doing something that would actually work. You don't have to build and test things like this to tell they aren't going to work on a meaningful scale. It is pretty clear it wont simply by considering where its getting its energy from and all the problems that come from that.

But as you said, they'd be slowing down regardless, wouldn't they?

They'd be slowing down already and that energy would be going into the batteries in the car to be used later by them to drive the car. The ramp would instead get a portion of that energy to power the city which would then not end up in the driver's batteries to power his car. Considering the driver already purchased that energy for his personal use and has implemented measures to recover it taking it is tantamount to stealing.

How would the ramp get a portion of the energy? I'm afraid I don't understand how the ramp is stealing the energy. My understanding of it was that the ramp gets the energy from the force of the car going over it or some such and the energy for the battery was a separate thing.

It basic conservation of energy. Energy does not pop out of nowhere or disappear into nowhere. Regenerative breaking works by converting the cars forward movement into electrical energy thereby slowing the car down. The ramp works by converting the cars forward movement into electrical energy and thereby slowing the car down. Its a little more complex in the case of the ramp but the net effect is that the car loses forward speed by going over it. Now the driver only wants to slow down so much and will get so much energy from regenerative breaking if he uses his breaks to slow down that much. However, if the ramp then slows him down further he now has to speed up, using energy, to get back to the speed he wanted. Alternatively, seeing the ramp and knowing it will slow him down the driver engages his regenerative breaks for a shorter period of time regaining less of the energy for his use with the rest going into the ramp.

Speed Bumps will do that anyway, won't they?

Frost heaves? Head in the clouds is nice but a practical foot firmly placed is also a plus.

There's a hydraulic form of regenerative braking that Ford's incorporated into a series of concept trucks too.

They're saying it reduces fuel use by 25-30% in stop and start conditions, such as travel through a city.

While it wouldn't be as effective in a car because of the lower vehicle weight, it could still be worthwhile seeing it would be compatible with non-electric cars.

It sounds like the energy is taken from the weight of the car passing over it moving a series of plates. Speed should not play a role in this; even if you came to a dead stop on one then resumed driving it sounds like it would generate the same amount of energy as if you passed over it at the maximum allowable speed.

I see no reason why this and regenerative braking should be mutually exclusive. Put together, they're enough to save a decent amount of energy.