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Don Foreman Don Foreman is offline
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Default Model engineering heat pumps

On Wed, 02 Sep 2009 21:38:15 -0500, "Lloyd E. Sponenburgh"
lloydspinsidemindspring.com wrote:

Richard J Kinch fired this volley in
:

1 KWH can pump 10,000 BTU in a 10 SEER heat pump. If we equate 746
watts to 1 HP, then you get 7460 BTUs pumped with 1 HP-hour. So
pumping 50 BTUs would take 50/7460 = 0.0067 HP-hour. That's about
0.08 HP for 5 minutes. But who knows what efficiency you could build
in that size. And how thirsty you are for a cold one.


I stand corrected. I failed to account for the fact that energy moved
isn't equal to energy input.

HOWSUMEVER... I'm not sure most 'mature' guys could output nearly a
tenth of a HP for five minutes, either. But I concede the error G.

LLoyd


This 'mature' guy (AKA oldfart) survivor of quintuple bypass and now
bearer of an ICD can output rather more than 74.6 watts (0.1HP) for
considerably more than 5 minutes. I did better than that in rehab last
summer and I'm considerably stronger now than I was then.

I joked at the time that they tortured us pedalling furiously to
produce energy they sold to third-world places like Iowa.