Re: electricity from a gym: quick calcs

On Tue, 18 Sep 2007 15:17:00 +0000, ehsjr wrote:
Rene Tschaggelar wrote:
ehsjr wrote:
Accordding to this link, 75 watts is sustainable on average:
http://www.humboldt.edu/~ccat/pedalpower/hec/hpeg/index.html

Where did you get yoyr 300 watt figure?

At the local enginering school, friends built a bike for
just this purpose. Driving a DC machine to illuminate
lamps. Every 50W, another lamp was added. That was 25
years ago. As I believe to remember 300W was just doable
for few minutes. We weren't bikers then, but are now.
So I'd assume these 300W to be doable for some while. Oh,
we're biking in the hills, not in the flat.

Thanks. That seems reasonable for well conditioned cyclists.

When I was in high school, the physics class did an experiment.
There was a two- or three-flight staircase, and guys would
volunteer to run from the bottom of the stairs to the top, timed.

Now, this wasn't restricted to legs - we were allowed to grab
the railings, vault, whatever we needed to do to get to the
top of that staicase as fast as humanly (teenagerly?) possible.
Then, the calcs were quite simple; the guy raises X pounds Y feet
in Z seconds. Some of the more athletic gus achieved almost a
horsepower (746 watts), for about six seconds. :-)

Cheers!
Rich

.

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