If Tour de France Powered the World

[mahatmakanejeeves]

We had a thread about this last November:

60 Minutes on this bicycle can power your home for 24 hours

If Tour de France Powered the World

by Tracy Moran

The Daily Dose

AUG 25 2016

....
The 198 men cycling in the annual Tour de France — women are still excluded — are among the world’s fittest, so perhaps it’s time to harness their energy for a greater good.
....

The bikers expend enough energy to light up the Eiffel Tower — which has 20,000 lightbulbs — for 3.2 days.

That same energy, from peddling a combined total of 432,957 miles, could power the Empire State Building for 48 minutes, the average French home for a whopping 663 days and the average American home for roughly 170 days. It’s also enough to drive a Tesla 18,000 miles, brew 114,356 pots of coffee and bake 773 turkeys.

The figures were gathered by using MET scores, average finish time and the average weight of Tour de France competitors to get the total number of calories burned. Then, by comparing these calories against data from the National Institutes of Health, researchers converted them into muscle energy, then changing calories into kilowatt-hours to get the equivalent electrical output per rider. On an individual basis, for perspective, these top racers are pedaling enough to power a 100-watt lightbulb for 258 hours or a washing machine for 51.6 hours.

{Edited to remove the chart, which had contrived units and other problems.}

Source • Mark Rosenthal for Ozy

[muriel_volestrangler]

1. "watts per hour"? "watts of power per mile"? The writer hasn't a clue about units

This article is pointless.

[mahatmakanejeeves]

2. I was thinking that she probably meant watt-hours for typical use.

Thus a dryer normally uses 3,400 watt-hours of energy drying a typical load, however that is defined. An electric razor uses 7 watt-hours of energy per shave. Something like that.

A closer look shows that a lot of stuff doesn't add up. I expect that it might get edited. If not, I can delete the OP.

Thanks for pointing that out.

[OKIsItJustMe]

3. Indeed… compare the last two lines

Last edited Mon Aug 29, 2016, 05:54 PM - Edit history (1)

The electric shaver and CFL bulb supposedly take significantly different “watts per hour” but would require the same number of hours of pedaling.

In the 80’s Phillip Morrison expressed it in terms of JDU’s (“Jelly Donut Units.”) Skip forward to 21:00 (or watch the whole thing, it’s great!)

[muriel_volestrangler]

4. Even if they got the units sorted out, that 30 (Wh?) is equivalent to 2 (hrs of peadlling?)

for a CFL bulb, and 7 (Wh?) is also equivalent to 2 (hrs of something?) doesn't make much sense - as you say, it doesn't add up.

For most of the figures in that infographic, the right hand side is about 1/14th of the left. Perhaps they screwed up the last figure, and it should be "1/2", not "2".

Perhaps they are trying to say you can generate 14 watts; and thus to power a 100W computer for an hour, you'd have to pedal for 7 hours (that would mean the title of the 2nd column is OK, and the first should just read "watts consumed&quot . But the article also says "the typical bike generator can produce only 100 watts" (and that looks more like the figures we were using in that previous thread), and 14 does seem really low. But "14" is also a figure they give as "14 watts of power per mile". If that should actually read "14 watt-hours of energy per mile", then perhaps the columns should read "watts consumed" and "pedaling distance for 1 hour of use".

[mahatmakanejeeves]

5. The chart is troublesome.

Hasta la vista, baby.