Low-cost system uses passing vehicles to generate electricity


December 2, 2013

The new system puts the weight of vehicles to use

The new system puts the weight of vehicles to use

Image Gallery (2 images)

Over the years, various researchers have developed systems in which the weight transferred through cars' wheels onto the road – or through pedestrians' feet onto the sidewalk – is used to generate electricity. These systems utilize piezoelectric materials, which convert mechanical stress into an electrical current. Such materials may be effective, but they're also too expensive for use in many parts of the world. That's why Mexican entrepreneur Héctor Ricardo Macías Hernández created his own rather ingenious alternative.

In Macías Hernández' system, small ramps made from a tough, tire-like polymer are embedded in the road, protruding 5 cm (2 in) above the surface. When cars drive over them, the ramps are temporarily pushed down.

When this happens, air is forced through a bellows that's attached to the underside of the ramp. That air travels through a hose, and is compressed in a storage tank. The stored compressed air is ultimately fed into a turbine, generating electricity.

Héctor Ricardo Macías Hernández, inventor of the system

The higher the amount of traffic where one of the ramps is present, the greater the amount of electricity that can be generated. Macías Hernández points out, however, that in lower-traffic areas, multiple ramps placed along the length of the road could be used to generate more electricity from each individual vehicle. He adds that the technology could also be used with pedestrian foot-traffic.

The system is currently still in development, with the support of the Mexican Institute of Industrial Property.

Source: Investigación y Desarrollo

About the Author
Ben Coxworth An experienced freelance writer, videographer and television producer, Ben's interest in all forms of innovation is particularly fanatical when it comes to human-powered transportation, film-making gear, environmentally-friendly technologies and anything that's designed to go underwater. He lives in Edmonton, Alberta, where he spends a lot of time going over the handlebars of his mountain bike, hanging out in off-leash parks, and wishing the Pacific Ocean wasn't so far away. All articles by Ben Coxworth

A better idea would be to harness energy without having pedestrians / drivers foot the bill. (...hello Solar, Hydro, Wind...)

In this scenario the people driving (or walking) would be the ones paying for this "low-cost" energy.

Basically, what we have here is an overly-complicated gasoline generator. (assuming the vehicles being driven are running on Gasoline).


No such thing as a free lunch. He's stealing energy in the form of higher gas consumption from each passing car.



Of course. The point of this system is to provide energy in places where an electrical grid is impossible or prohibitively expensive.


Well, if you install it as speed bumps, you practically kill two birds with one stone.


Who in their right mind would drive down a road fitted with them? what you have is a speed hump that depresses slightly - NOT the the ideal thing to have on a busy open road!


How many passing trucks will this bellows mechanism withstand?


Given that few people have energy capture when breaking this could be effectively used for braking down hills at no cost to the motorist. Energy dissipated through braking systems could in fact be passed to the grid at no cost to the motorist (except maybe some wear on the suspension) and with savings on the brakes.


Will ultimately fail on at least 3 counts -

a): Manufacturers spend millions looking for a 'smoother' ride for their car drivers, complaints would multiply expotentially.

b): Rolling out enough 'track' to generate sufficient power for reasonable 'payback' time will probably end up costing too much.

c): Can you even try to imagine a whole road made of little speed bumps? (See point a). The vibration issues would be hard to overcome.

The Skud

It actually makes an ideal speed hump. A larger bellows would generate more power, intimidate those speeding into a safe speed, depress when driven over to generate power and reduce wear on vehicle suspension. It's a win, win, win for power users, pedestrians and maintenance bills of car owners.

Paul Robertson

This is plain, outright theft.

Why is gizmag even telling us about it?


Forget the speed bumps people. Drivers would hardly feel it, if at all, because it "gives" as they roll over. So no energy thievery here. Install series of them in high traffic areas where 100's of thousands of cars go through every day, and you have something worth exploring. This is actually a brilliant idea.

The biggest challenge is to make it durable enough to take the worst beating from cars and hot/cold/wet elements from nature. If this can be done, the potential is ENORMOUS.


@ owlbeyou: "no energy thievery here"

Energy can neither be created nor destroyed, sorry.

One of the major problems with this idea has to be the size of the additional costs incurred when resurfacing the road.

Also, I wonder how they will cope with a vehicle braking diagonally with its wheels locked.

There are not many areas of this device that aren't open to question.

Mel Tisdale

Hmm so could put it on a hill, but only on the downward side to reduce increases in car consumptions - but limits it to the downward side you have to fit twice as many, but agrees with being an advantage to slowing a car down rather then being an expensive gasoline energy generator. Vibrations from 'rumble' strips or slow down markings are already present at junctions so as other posters point out would be possible there without an increase in driver discomfort - if there was any. So sounds interesting but needs some good implementation


Robt has it right It will lower the mileage for each car traveling over the bumps. In addition to lowering gas mileage , ride quality is reduced , (although from my experiences in Mexico on many roads this would not be noticed) and tire wear will increase. I would also be skeptical of the maintenance required for all of these bellows. the surface of a road is littered with abrasive material that can wear on the bellows , also there would need to be a check valve and an intake port for the air that is to be pump that would be exposed to the environment. I can see these being plugged, or seizing open etc. Sounds like a good project for government funding.


Bad roads already steal energy from our cars; this system would simply be another inefficiency in the roadbed, so the loss of energy to the car would probably be very small when compared to one's entire commute. The problem I see with the system is that it will require a lot of up-front labor cost to install. Thus, how long until the systems repays itself? Then there is the issue of the spring. Mechanical things fail. Rust. Dirt. Animals. Ice in cold climates. These things will cause a metal spring to fail or function improperly.

Chad Wilson

An acceptable place to "rob" energy from cars is to do it on a steep downward slope where cars have to brake anyway.


Have I slept for 4 months? It must be April!


Air is being compressed so work is being done and that requires energy, no matter how little, from each passing individual vehicle. This is just another "tax" on the motorist in that everybody contributes a little and the "recipient" gains a lot. You can fool some of the people all of the time and all of the people some of the time, but......this is highway robbery!


Promising idea. Instead of compressed air, they could be made to power a gyro.


I liked the article, as it inspired me to propose a more practical solution.

Use the new devices that convert WiFi into electrical power. The devices would capture the electric interference produced by vehicle ignition systems.

Robert Fallin

Look, if you’re going to steal energy from passing cars, be honest about it.

You could put solar cells on the meridian of the highway and get REAL energy you didn’t have to steal.

William Carr

All this debate is good. From good ideas come better ones. Of course, you can't get something from nothing, that's a fact, but the energy captured from the traffic is NEGLIGIBLE when you're only 1/100,000th of the formula. And undulations in the road are even bigger energy thieves. Between this concept and solar panels, it would depend on which system is doing its job more efficiently.

If you really wanted to get sneaky, you can install micro-generators in the exercise machines in a network of gyms. People would get their workouts, and would be providing electricity for the grid, with or without their knowledge:-)


You could generate more power if you put these devices in the chairs of people who sit in them while in front of their computers reading about this stuff!


Each car passing over the raised area of the road, compressing air uses more energy to go up and down on the air pumps, plus the frictional losses of working the pumps, compressing and transporting the compressed air in the pipes. Combined, the cars will waste far more energy, pumping air, than the system produces in electrical energy. It is impossible to spend energy, to move any generating equipment and still produce the same amount of energy, with 100% efficiency. There are always a large amount of losses; friction, kinetic energy losses, loss in the generating equipment and electrical transformation and transmission losses. With just a pure guess, more than half of the energy (50%+) the cars use to go up and down on the ramps would be lost. The goal is to save energy, which is produced by fossil fuels and in general energy used in transportation. This system would add to the losses.


Putting these on a downhill run where braking happens is an interesting concept. Traction is already reduced due to load transfer and you want to add bumps?

Remember that air (as opposed to liquids) compresses, and the bellows system may just get tight as it compresses one whole inch and not send much (if any) air out.

Get a hold of a pneumatics guy and talk about valves and hoses and air springs. You have lots of expense here for a system of any decent size.

All the other maintenance issues aside, that pit will fill up with crap so fast it will make your head spin.

And it will be noisy.

Only a government would take something like this seriously.

Bruce H. Anderson

Not only is it energy theft, it is energy theft from petroleum as a source. Isn't that generally frowned upon among green energy advocates?

Post a Comment

Login with your Gizmag account:

Related Articles
Looking for something? Search our articles