Posted by Morris Dovey on December 21, 2008, 10:15 pm
Not so - you're confusing heat and temperature. They're /not/ synonyms.
Resistance to airflow is an impediment to getting the heat out of the
box and to the space where we want it.
I agree completely - and it's been most satisfying to be able to confirm
with first hand experiences that the physics I studied in school really
does hold true for real-world, practical applications. :)
The customer who heats this entire building with only two 8'x6' passive
panels seems equally satisfied:
A knowledge of basic physics is an excellent and very practical tool.
DeSoto, Iowa USA
Posted by schooner on December 21, 2008, 11:25 pm
Care to post some data on your panels, ie typical BTUs and so on? Be
interested to see what they produce.
Posted by Morris Dovey on December 22, 2008, 2:05 am
Nope, I'm still not posting performance claims for the same reasons I
posted here several years back - a good decision, since today's panels
are considerably more efficient, and it wouldn't be a good thing to be
haunted by numbers for obsolete panels.
I would much rather use the group as a conduit for sharing information
that more directly helps everyone (including myself) build better solar
If that info would really be helpful to you, then you're welcome to take
your own measurements - and I'm aware of a couple of customers who'd
probably be pleased to let you measure the performance of their panels,
including the guy in Ontario who started the thread in rec.woodworking
(where I encourage the guys who have the skills and tools to build their
own): "Solar heat for the shop. ^5's Morris!" It was a fairly typical
customer reaction. Also fairly typical, he doesn't seem to care much
about any numbers from me.
DeSoto, Iowa USA
Posted by schooner on December 22, 2008, 10:35 am
Ok nevermind. Just find it interesting you claim high efficiency panels and
state how you've proven the physics works yet have no numbers on actual
performance. I notice you seem to also state the same on your website, that
bascially performance numbers are lies anyway. It is easy for someone to
first be impressed with any panel when you have nothing to compare too. I
know we were pretty impressed with our first panels as well until we took
some readings and found the overall performance lower than expected and from
there improved things. A few simple numbers on the tempurature delta and
airflow is all I was looking for, as many others have posted for their
panels. Thanks anyway I guess, to each their own, I'll just have to take
your posts with a grain of salt as we have nothing to go on to compare to
Posted by Morris Dovey on December 22, 2008, 1:11 pm
<grin> /I/ didn't have to prove the physics works - that had already
been done by folks a lot smarter than I. You can apply the same
knowledge or not, as suits you.
Choosing not to publish the numbers is not the same as not having them.
I see performance numbers used all too frequently to mislead customers -
mileage estimates for automobiles, horsepower ratings on tools, and
performance numbers on audio equipment appear generally questionable;
and I choose to not play that game with you or anyone else.
It is sufficient for my purposes that the expectations of knowledgeable
customers are consistently exceeded. :)
I've had similar experiences, and ended up building and discarding more
panel designs than I've liked in the effort to find what works best.
What you've missed is that I'm not trying to sell you panels - I'm
trying to share a bit of what my experience has shown me - and in a
public forum where any error in the inferences I've made can be
corrected by anyone who has better information.
And yes, people who are shopping for panels should definitely view
performance claims with the same skepticism I feel every time I see the
6.5 hp rating on my 115V ShopVac. :)
DeSoto, Iowa USA