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"Crowd Farm" to Collect Energy?
Cain writes to mention that a couple of MIT students would like to harness the mechanical power of large groups of people. "A Crowd Farm in Boston's South Station railway terminal would work like this: A responsive sub-flooring system made up of blocks that depress slightly under the force of human steps would be installed beneath the station's main lobby. The slippage of the blocks against one another as people walked would generate power through the principle of the dynamo, a device that converts the energy of motion into that of an electric current."
Because you only go through the turnstiles once, but you take thousands of steps through the station.
The slippage of the blocks against one another as people walked would generate power through the principle of the dynamo, a device that converts the energy of motion into that of an electric current.
Ever walked in sand? It's many, many times slower and harder. So what are they going to do with travellers that are already exhausted from travel? Piss them off with a hard-to-walk-on floor. There's also NEVER 30,000 people in South Station; where did they get that number from? Let's put this in perspective: Fenway stadium, average summer weekend game, is ~30,000 people. Even at peak commuter rush hour, I think you'd be hard pressed to find even one TENTH that number of people at any one time.
The electric current generated by the Crowd Farm could then be used for educational purposes, such as lighting up a sign about energy.
Wow. Oh. Wow.
The MBTA (which is BILLIONS of dollars in debt) and Amtrak (same...) have much bigger priorities than some stupid concept like this. How about PA systems which actually work (and don't broadcast "please report suspicious packages, safety is our NUMBER ONE PRIORITY!" every 2 minutes), bus fareboxes which work in cold weather, online lookup+refilling of Charliecard balances, integration of Charliecards into the parking garages, or online bus status? (the busses have been equipped for years with such a capability.)
Or even the "signaling" systems in the orange line which are constantly broken, or replacing more cars on the green line (the newer cars use much more efficient motors which are also capable of regenerative braking), same for the red line. The entire orange and blue lines are also non-regenerative braking as well.
Please help metamoderate.
yes the energy has to come from somewhere, but wouldn't the plates act as a shock absorber, rather than the downward energy being absorbed by your shin, it's being depressed down. If anything, with the appropriate tension it'd almost make it easier/more comfortable to walk, similar to certain rubberized walking surfaces. less impact on your shins and knees. the energy that is being used already exists and is being wasted walking on concrete (being absorbed by the shin and knee). so the law of thermodynamics is maintained, it just converts wasted energy into useful energy.
The First Law of Thermodynamics states that energy cannot be created from nothing. I believe that applies in Britain as well as the U.S., so the energy to power those plates came from somewhere. To wit, from the automobiles. The Second Law of Thermodynamics tells us that any time energy is transferred, some will be lost to entropy. Essentially such a device is A) using petrol in the cars to power the streetlights, and B) doing so less efficiently than would be putting petrol in the street lights and burning it there. It's a waste of fuel; indeed, a waste of dirty-burning fuel that creates CO2 (a greenhouse gas) and NO2 (smog). A horrible idea.
[Sir Garlon] is the marvellest knight that is now living, for he destroyeth many good knights, for he goeth invisible.
Besides, it's not like you're spending your time generating power
Walk over concrete. Now walk over sand. Which one takes more effort? The mechanical motion of the floor absorbs energy that would otherwise rebound from the shoe sole, or would never have been expended in the first place.
I am one of many. My idea is not unique, nor do I expect my voice alone to sway you. I speak in a chorus of opinion.
Instead of tiles and dynamos, which would be constantly creating an uneven surface and making things difficult for children, the elderly, people in wheelchairs, people on crutches, etc., why wouldn't you just use a rubber surface with piezos on the underside?
When walking on a hard surface, the energy of each step is dissipated in the form of vibration, sound, and heat, most of which is absorbed by your legs. Walking on a slightly softer (not sand soft, though) surface, allows the surface to depress slightly, which absorbs most of the impact. The reason walking on sand is much harder than walking on a hard surface is that the sand moves out of the way when you push against it, causing you to exert more muscle effort to take the same size step. On a soft surface that has the proper "springiness", the floor won't move out of the way as much. The combination of springy floor and floors that bend slightly on every step is exceedingly comfortable to walk on. Ask anyone who's walked on one of those horizontal escalators in airports with the rubber belt instead of the escalator steps (I know there are some in O'Hare airport; I'm sure there are other places, too). You feel positively lighter.
If we attached hundreds of tiny piezoelectric devices per square foot on the underside of the floor, they will be able to capture the energy in the bending of the floor. The advantage of this is that the wiring infrastructure could be printed, like a circuit board, on the underside of rubber sections of floor, each of which could be swapped out for maintenance or replacement individually. Economies of scale would be in effect, since production of each floor tile would be identical to all the others before installation. Additionally, this floor might even be *more* comfortable than standard tile, and still allows for free movement of kids, the elderly, and the handicapped.
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