A force is not a source of energy at least not in that way. In this case the car rides up a slight incline in while pushing it down. The moving up the incline itself takes some kinetic energy from the car which it would normally get back from going back down the other side. The only problem is that the incline falls while the car is on it and steals the energy. Also, the design of the ramp redirects some of the forward force of the car downward in order to power the generator resulting in gaining more energy than just the energy the car used to climb the incline. Of course this all comes back to conservation of energy. If the weight of a car, or anything else was a source or electricity, we would just pile something big and heavy on a generator and solve our energy crisis.

This thing would literally steal from anyone using regenerative breaking and isn't really that big of a source of energy.

Speed bumps don't really slow a car down. That is unless you go over them to fast and scrape the belly of your car or worse. The car does slow down as the wheels go up one side but then it gets all that back, well 99% of that back, when it rolls down the other side. This ramp if it wanted to produce 10 kW for 10 seconds from a 1.5 ton car passing over it would need to slow the car down by 27mph. So if the car was going 30mph it would be going 3mph after crossing the ramp. With a speed bump you'd be hard pressed to measure the difference in speed. (Note that value is only .0277 kWh which is basically nothing in terms of electrical demand.)

When I hit a speed bump, no matter what speed I'm going, I'm not going anywhere near that speed when I come off it. You certainly know your stuff and have a greater understanding of this subject matter then I do, but I'm not going to accept that 'speed bumps don't really slow a car down' when over a decade of driving over them tells me otherwise, sorry.

There's also the fact that you generally have to slow down anyway to avoid beating your car up.

It might not be speed bumps force your car to slow down but they certainly do force you to make your car go slower, for the most part.

On the OP; seems like some tech with the right idea but we just don't have the kind of capabilities for it to be effective, in cost as well as others.

Certainly the shocks in your car eat up some of the energy of going over a speed bump but not much and you could reclaim that too. I've been driving just under a decade and I've never really experienced a significant speed reduction from a speed bump. (Any significant decrease in speed was probably because you let off the accelerator and was more due to friction in the various parts of the car than the bump itself.) Certainly nothing in the range of 27 mph. Lets assume that a 1.5 ton car loses 5 mph going over a speed bump. (Which from my experience is very high.) That's about .000944 kWh worth of energy. If we then size the ramp to take this much energy and assume 90% (which is very high) efficiency of conversion to electricity that is .000850 kWh of electricity per car.

If we assume 1 car every second for 10 hours each day (36000 cars a day going over it) that is 31 kWh of electricity per day. That is 11,000 kWh hours a year. That's about 350,000 of them to power the US and there is no way we have 350,000 places that gets that much traffic, and needs a speed bump. If we assume a car every 5 seconds for 10 hours (7,200 cars) we'd need about 1.8 million. A car every 10 seconds (3,600 cars) means 3.5 million. In reality we'd be lucky to find places that need speed bumps that saw 500 or 600 cars a day which is basically .5 kWh per day or 186kWh a year which means we'd need roughly 21 million of them.

In reality to keep them more in line with the speed bumps you would have to limit them to 1mph or less of speed decrease and hope someone doesn't start reclaiming the energy lost through the shocks.

Already addressed that and how there are much better ways to get that energy back.

Its just not physically possible to get any sizable amount of power from this system.

In my experience speed bumps slow you down else you're in a large vehicle (SUV) and can just ignore it or you'll be pulling out your wallet to pay the mechanic for new shocks much sooner than is actually necessary.

Pity, that money you could have saved could have been invested in these electro-kinetic-whatchama ramps.

Doesn't really seem like a bad idea to me, for intensely high traffic areas like bridges or something. It would even be neat if they could be designed to turn on and off based on traffic density. Of course that'd just make them more complicated and thus more expensive. But an answer to our energy crisis? No, I don't think so.

Okay, so looking at the video, it strikes me that the speed at which a car hits it is much less of an issue than enough cars doing so at a reasonable interval to keep it spinning underneath. This is NOT a speed bump. They even say the point is to keep the ride as smooth as possible for the people going over this thing.

In fact, the unit in the video is specifically stated to be for low-speed use.

Looking at that, there isn't a parking lot in the world this thing couldn't be installed in multiple times over, or designated turn lanes, roundabouts, or bicycle lanes. Anywhere that has a low speed limit would be fair game.

Will it solve our energy needs? Likely not. But at least it can give us a bit of power back to no real detriment to the shocks of our cars or the speed that's posted.

Read what I posted. These things get energy by slowing the car down and therefore would only be placed in places where the cars should be slowing down. Most of those places are places where we put speed bumps but you could kind of put them at some slower intersections. Further, the use of these to reduce the speed of a car that has regenerative breaking is basically stealing.

Aside from that the actual amount of energy than can harvest is less the microscopic unless you want to very significantly slow the cars that pass over them. For example if we limited them to slowing cars down by 5 mph and wanted only 10% of our electricity to come from them we would still probably need over 2 million just in the US alone. If we limited them to a much more realistic speed decrease of 1 mph and still wanted 10% of our electricity we would need 10 million of them. Anything less than 10% is so insignificant as to not be worth even discussing. We can easily get that with moderate efficiency changes which would be much cheaper for everyone.

Knowing my limits, I'm simply going to ask. If one were driving let's say 25 mph and came to a halt at an intersection, and had the reflexive brakes previously mentioned, how much energy would the action of coming to a halt at said intersection normally provide? And beyond that, how much energy would actually be stolen if one of those devices were located at said intersection? I'm just wondering if this theft is the equivalent of losing a bit of water say by pouring it into too shallow a container and having some splash out over the sides.

Beyond that, while this wouldn't be a power source capable of running a stable power grid, when we do shift to alternative fuel sources such as batteries, etc, for vehicles, wouldn't it in theory be possible to use these ramps as a way of charging said batteries? Again, limited knowledge in my question, but couldn't a city or organization that has a fleet of cars store said power and then use it to recharge their vehicles as necessary with any excess diverted as a donation?

Before I go onto the energy bit its important to know that it is basically impossible to use one of these to slow a car a significant amount. Assuming, generously, that the ramp is 9ft long and the car is decelerated evenly the whole way bring to a stop from 25 mph means a negative acceleration of 4.64 g. If we assume that we want to limit the acceleration to .1 g then you can slow a car from 3.67 mph to 0 mph in 9 ft. Alternatively you can slow a car from 25 mph to about 0 mph in 414 ft using 46 of the ramps. I figure .1 g is about what you could do comfortably. A 100 pound passenger would feel a 10 pound forward force and a 200 pound passenger would feel a 20 pound forward force. Even that might be a bit unsettling.

So we know you could never hope to realistically convert much more than to be safe lets say about 3 mph worth of kinetic energy into electricity. If we assume a 1.5 ton car to be about average that translates to about .000340 kWh per car. Assuming a semi realistic, but probably high, 70% conversion to electricity (the joints in the ramp, the transfer of the energy to a fly wheel and then to a generator, and energy lost in the shocks of the car, being most of the losses) that's .000238 kWh of electricity per car. Here were I live we spend about 12 cents per kWh so that's about .0028 cents, or just under 3 thousandths of a cent, worth of electricity. That means it would take about 1000 cars to get one cent worth of electricity.

The regenerative breaking system of a car can be designed so that there are very few moving parts between the wheels and generator. They could theoretically eventually become around 80% efficient. Further the regenerative breaks can easily act over the entire 25 mph slow down. So the regenerative breaking system would recover more of the energy over a greater speed range. Technically speaking the amount stolen from the driver is minuscule but people can be touchy. Aside from that its not really worth it in terms of the amount of energy you get. It would take forever just to pay for itself and you couldn't power much with it. The time, effort, and money would be much better spent installing small solar/wind systems and increasing energy efficiency.

Damn, wish I'd been paying attention earlier.

Isn't the problem with wind and solar power the fact you have to build tons of windmills and solar panels to collect said energy? I've kinda figured those two options are nice in certain areas on a small scale, but on a larger scale you run into power-to-land-occupied (basically to get a decent amount of power, you would need a ton of land/whatever to build a sufficient amount of solar panels or windmills) or problems and then fights start with other groups over the consequences of building these things (Apparently the windmills have a bad habit of butchering birds and bats, and the main areas they'd be built are major migratory routes - can't remember where I saw that tidbit).

Personally, I'm in favor of nuclear fission and fusion (assuming if the government will back it enough to get it developed sooner than the standard 50yrs+ answer we keep getting) power plants, along with hydrogen fuel cells and other gas-electric hybrids for vehicles.