re: our solar hot air is really hot!
21 jul 2001
deris jeannette wrote:
>you may be surprised at the heating numbers, but they are true and all
>of our many heater owners around the us have confirmed them...
i'm surprised because you claim they collect more heat than the sun
can provide, given their face area. you indicate 75x40 = 3k btu/h
with 2x4x250 = 2k btu/h of incident sun... 150% efficiency, while
honest vendors don't claim more than 75%.
>if anything is flawed with our information, it could be the cfm rating
>as stated by the fan manufacturers... we state the cfm air flow the
>fan makers indicate, not the exit cfm air flow.
that is dishonest.
>we have to do that, since we haven't yet found a place to accurately
>measure the air vent out without spending a lot of money.
you might measure how many seconds it takes to fill a dry cleaner bag.
>use your own math to figure how many pv's it would take to generate
>the same amount of heat one solar space heater could make. we're
>talking many thousands of dollars for pv, and only hundreds for solar
>thermal air. that's why solar electric is seldom used for heating spaces.