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aemeijers

On 10/23/2010 7:47 AM, wrote:
On Oct 22, 8:24 pm, wrote:
On 10/22/2010 4:11 PM, HeyBub wrote:

wrote:

I can be persuaded otherwise - just gimme the facts (I know maths is
hard, but try).

Your problem is not math. Your problem is how you dishonestly approach
the entirety of the issue.

Please explain why you insist that solar photo voltaics must provide
all of our electricity in order to be a viable supplier of some of our
electricity.

I don't insist that that anything be a sole source of electricity. I never
said I did, nor do I believe it.

To repeat what I said:

"My argument is it is impossible to run this [entire] country/state/city off
of sunbeams."

For those applications where it is possible to run some piddly thing off of
sunbeams, most of the time so doing is roughly equivalent to using mahogany
to toast marshmallows.

You ain't listening, Bub. Not all applications require electricity. Just
as a trivial example, a coil of black pipe on a garage roof makes a
dandy pool or house water pre-heater, so the regular water heater
doesn't have to work so hard. Yes, you do have to remember to take it
out of the circuit and drain it when winter comes, but that can be as
simple as turning a couple of valves if you do it right. Very popular up
here in frozen north, to extend pool season a couple of weeks.

If only it were anywhere near that simple. A coil of black pipe on a
garage roof doesn't make a dandy pool heater. Not one that's going to
make a rat's ass difference in extending the pool season by a couple
of weeks in even the mid-Atlantic region, let alone the frozen
north. Go to any of the websites that sell or discuss solar pool
heating and you'll find that the solar collector needs to be about the
size of the pool surface. So, a 40X20 pool needs an 800 sq ft
collector on a south facing roof. Don't have a south facing roof?
Then you can use a west facing roof, but then you need an even larger
collector because there is less sun. So, how big is that garage
roof? And even then, you'll find that there are all caveats that go
with it, like recommending that you also use a pool cover to cut down
heat loss. Don't want to screw around with a pool cover? Then you
need an even bigger solar collector. That's why gas pool heaters are
typically 200 to 400K BTUs. You don't get that kind of heat out of a
roll of black pipe.

As for using that loop to pre-heat water for the water heater in the
summer, that doesn't compute either. Many homes are going to draw
most of the hot water in the evening or early morning when there is
little or no sun. My entire gas bill to heat water in the summer is
under $20 a month. Not much incentive to go screwing around with
installing a "coil" of black pipe on the roof, especially when you
realize it;s not quite that simple.

That's not to say solar pool heating doesn;t work. It works in
places like Florida or AZ, where there is lots of sun and the cool
down over night is far less than what it is in NY. Even there, it
takes a system like described above, not a roll of pipe.

No, solar
will never replace all other energy sources, especially those that
require the very convenient but luxurious form of energy known as
electricity. But there is low hanging fruit out there, for people who
will open their eyes.

--
aem sends...- Hide quoted text -

- Show quoted text -

I'm no expert, so I'll take your word for it. But I see a whole lot of
coils of pipe on roofs here in SW MI, for people with pools.

--
aem sends...