> From: "Jed Rothwell" <[email protected]>
> To: [email protected]
> Sent: Monday, May 27, 2013 2:12:49 PM
> Subject: Re: [Vo]:Ekstrom critique of Levi et al.
>
> For people not following the discussion, Ekström misunderstood the
> "e" (emissivity) ratio. He wrote:
>
> "The emissivity for stainless steel could have any value from 0.8 to
> 0.075 [2]. The lower value would
> obviously yield a much lower net power, in fact it could easily make
> COP=1."
>
>
> He has this backwards. The lower value would yield a much higher
> temperature, meaning higher power. The most conservative setting is
> 1.
>
>
> Not only did Ekström get this wrong, so did Cude (it goes without
> saying), some blogger named Motl, and Andrew. Andrew realized his
> mistake. Ekström, Cude and Motl will never admit they were wrong.
>
>
> - Jed
And just in case you're wondering how e effects the calculated power
P = a . e . (T1^4 - T0^4) -- T1 actual, T0 ambient
a e Tc Tk P
area 18 1.00E-10 0.8 564.1 837.1 38.84 <=== lower "e"
OVER-estimates the power
area 19 1.00E-10 1 496.6 769.6 34.52
area 20 1.00E-10 0.95 511.7 784.7 35.49
(I set a to an arbitrary value just to make the numbers easy to see).
