You’re all the same. You criticize what you don’t understand. You criticize when it’s simplified for you. You demand the real math when you can’t apply common sense to a dumbed down version. You offer no facts, figures, or math of your own to support your gut reaction that you feel I’m wrong.

The poster says the turnstiles generate 13.6% of the power needed. The R142 type B subway car, which is a very modern car in use in the New York subway, draws 313200 watts/hour and has a capacity of 188 people. The most generous figures I have found for power generated by physical human exertion are listed at 75-150 watts per hour with footnotes indicating that professional athletes can output nearly double this for short periods of time (minutes).

So let us assume we have an Olympic athlete about to get in a train car along with 187 of his friends and they can each output that full 300 watts while pushing through a turnstile. Well they aren’t going to be putting out 300 watts for a full hour because it doesn’t take an hour to push through a turnstile. Let’s say it takes 6 full seconds to get through that turnstile (which is ridiculously generous in that 6 seconds would be a long time to get through a turnstile).

188 Olympic athletes TIMES 6 seconds per athlete going through the turnstile at full power EQUALS 300 watts for 1128 seconds OR 18.8 minutes. That gives us a very oddball measurement so let’s convert that to kilowatt hours. 18.8 minutes divided by a 60 minute hour gives us a fraction of almost 1/3 but is slightly less; written in decimal format it’s 0.313? . That notation means the last 3 continues indefinitely (0.3133333333333333). So if we multiply the 300 watts/hour of human output times the fraction of an hour we had that output, we get a figure of 94 watts/hour or 0.094 kilowatt hours.

A subway car full of 188 Olympic athletes who each generated the maximum conceivable human output pushing through a turnstile attached to a 100% efficient (read:magical) generator would produce enough power to run that car for…

313200 watts needed to power the car for an hour divided by 3600 seconds in an hour = 87 watts per second or 0.087 kilowatt hours per second.

0.094 kilowatt hours total generated by the Olympic athletes divided by the 0.087 kilowatt hours per second drawn by the train car equals enough power to run the car for a FULL 1.080459770114943 seconds.

Going back to the poster, that would be enough power to run the car 13.6% of a 7.944557133198107 second trip. If we assume they have to push through turnstiles at the beginning and end of the trip, they’ve generated enough power to account for 13.6% of a 15.88911426639621 trip.

Now, granted, the power draw of the car is not constant given the variable speeds of the train, wind resistance, the weight of the human cargo, etc. HOWEVER they do draw full power when accelerating so assuming our Olympic athletes boarded the train when it was not moving, they’ve provided enough power to accelerate to almost 40 mph before drifting to a stop (that’s 15.whatever seconds times 2.5MPH per second of acceleration).

BUT it doesn’t take 6 seconds to go through a turnstile, the turnstiles are not attached to generators (magical or otherwise), the people going through them are not Olympic athletes, and they don’t have to use their maximum physical exertion to push through.

Is that enough facts, figures, and math?