Solar Guppy wrote:

And what does a 2 kWh system cost 15,000 mean ?

What it says. You buy (not build) a complete
2 kW system for $15,000. See below

is that what you paid or

No. There was a long thread in alt.engineering.electrical
discussing this - it's the price mentioned by a guy in
Maine for a commercial system. There's a guy off grid in
California who built his own, like you did. His cost for
solar + inverter, not including batteries & DC instrumentation,
was about 10K for 4 kW. See the site for details:
http://www.electronconnection.com/Media/OurSystem.pdf

just some made up numbers like your 16kWr per day which is pure fiction ..

Not "pure fiction". I clearly labeled it an assumption,
which is WAY different than "pure fiction". Here's
the quote, since you may have missed the first word:
"Assuming an average of 8 hours per day of 2kW per hour,
that solar system would give me 16 kWh. "


I built my 6 kWh system for 17K ...

I don't doubt that. Your write up lends credence to
the much higher cost of a commercial system vs a
do-it-yourself system. You indicated it was very
labor intensive to build the first one, taking over
5 months of your spare time. A first time builder
would go well over the 6 days labor you cited on your
second build. In any event, the labor cost would be
borne in the purchase price of a commercial system.


www.solar-guppy.com , you can see my invoices and the system installed in
the photo gallery. Also under real-time status you can see the energy being
delivered ... , anyone can buy the parts today for a similar amount , check
out the solar deals sections for links
http://www.solar-guppy.com/forum/viewforum.php?f=12 as examples.

My average per day is about 24kWr/day so far (3 months) , my electrical
rate is now 12 cents kWr (they have raised the rates about 2 cents kWh in
the least year , more increases to come for sure)

Your average proves that my assumption is way too
high. Perhaps that's what you meant by "pure fiction".
Anyway, your 6 kW system produces 24kWhr/day in
Florida - I would expect lower if it was installed
here (in NY). And it means best case, a 2kW system
here would produce about 1/3 that or about 1/2 what
I assumed. That doubles the "payback" time - which
would never happen with the 2kW system at $15,000
here.



24 * .12 = 2.88 .. 17,000 / 2.88 = 5902 (days) = 16.17 years My , Real
system , My real rates NO REBATES ...

And at $17,000 for the system, your mortgage cost
assuming 25 years, 7% will be over $36,000. Therefore,
your *real* payback is 36000/2.88 = 12500 (days) = 34.25
years. That assumes your system requires no replacement
parts, no regular maintenance costs, and does not degrade
over time, for the full 34 + years.


Do the same thing in California , where 65 % of the cost is covered (50%
materials , 15% state-tax rebate) and the payback is reduced to 17k * .45 =
7650 ... 7650 / 2.88 2656 (days) = 7.27 years .. its actually much better in
CA than this since the rates can be TOU (time of use) , the typical CA rates
are .15 - .25 kWhr ... putting the payback at 3.49 years at 25 cents kWh ( a
typical afternoon TOU rate) ....





wrote in message
...


"Watson A.Name \"Watt Sun - the Dark Remover\"" wrote:

Joel Kolstad wrote:
Watson A.Name - "Watt Sun, the Dark Remover"
wrote:

My attitude is that rather than try to do this (and in the process
lose
reliability), it's better to go supersize on the cells, add more area
and overall capacity to get you thru the cloudy days, and have a
higher
capacity overall.


The argument usually goes that getting, say, 10-20% more power from a
better
charge controller (one of these so-called 'maximum power point
controllers')
can be cheaper (in additional expenditures) than getting 10-20% larger
panels. It's sometimes difficult to show, though, particularly on
small
systems -- but MPPT controllers have been getting cheaper for awhile,
now,
and I expect that eventually all but the cheapest/smallest will have
this
functionality.

Last nite (Tue, 9pm) I watched a prog on PBS that was about getting
people to use more renewable resources, hosted by Cameron Diaz (hot
blonde movie star), who drives a Prius. They talked about getting every
home to have a solar panel, and selling power back to the utility co.
She also said that if everyone in the U.S. drove a hybrid vehicle, we
could completely eliminate oil shipments from the middle east. Well,
I'd go out and buy a Prius, but one of the guys at work has had his new
Prius since xmas and it took him 4 months or so to get it after
submitting a $500 earnest check to several dealerships to get on their
waiting list. They say they're trying to make more of them, but I think
they really don't want the prices to fall, since they're expensive to
make. In any case I'd like more solar power, but the initial outlay is
_not_ cheap.


Nor does it pay for itself in any reasonable time,
if at all, if you are grid connected. (If you need to
spend a huge amount to get connected to the grid,
solar can become very attractive.)

A guy in Florida quoted 48 years pay back time. I ran
the numbers for my home - over 40 years, and I pay 13
cents per kwh. A 2 kW system costs $15000. Assuming
an average of 8 hours per day of 2kW per hour, that
solar system would give me 16 kWh. I pay 16*.13 or
$2.08 for 16 kWh. Works out to 19+ years for payback,
if you don't count on mortgage payments for the system.
Add that in, and the cost of a $15000 system is
much worse - over 30,000 in a 25 year, 7% mortgage.