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Posted by dold on October 18, 2007, 3:41 pm

Provides feedback about the financial viability of a system in

Provides feedback about the financial viability of a system.

Clarence A Dold - Hidden Valley Lake, CA, USA  GPS: 38.8,-122.5

Posted by NRG on October 18, 2007, 8:08 pm

This is very very helpful.  It definitely appears that solar is getting
closer to some sort of breakeven.

I put in my zip code and left everything else at default, and found that the
system would cost $,000 and save about $00 a year, giving a rough payback
period of 10 years.  I'm also coming up with an IRR calculation of 7.75%,
assuming that the panels last 20 years, which is apparently very reasonable.

A darn good investment.


Posted by Mike Payne on October 18, 2007, 8:47 pm
 Other possibilities you might want to consider are things like

1.  If I need to sell the house next year can I find someone that will give
me $000 extra for it because of the installed solar?

2.  If a lightning strike wipes out most of the system what will it cost to
get replaced? Insurance deductibles? Replacement cost or current value?

3.  If they invent PV panels that are more efficient or cheaper in two years
how stupid will I feel for buying this year?

4.  If Gore gets elected and Congress passes a 75% rebate on PV systems how
stupid will I feel for buying this year?

In a perfect world where you never move, rebates never change, and things
never break then buying solar can make financial sense in some states.  It
just doesn't happen too often in the real world where I can buy all the
power I want for 11 cents a KWH.

I would be the first in line if they would half the cost, double the power
per sq. ft., and make the entire system plug and play.



Posted by dold on October 18, 2007, 9:49 pm
If not, I'd take it with me.  Showing someone the past year or two of PG&E
bills might indicate the value.

Same as the roof.  Mine is at replacement value.

That doesn't seem to be my real world.

How is that true, since questions 1-4 would still prevent you from buying?

Clarence A Dold - Hidden Valley Lake, CA, USA  GPS: 38.8,-122.5

Posted by Anthony Matonak on October 19, 2007, 3:52 am
 Mike Payne wrote:

If they don't, as the other fellow said, there is nothing stopping you
from taking it with you or selling just the PV system to someone else.
Since there is such a high demand for PV these days, you can get almost
as much for a used system as for a new one.

The same as if lightning strike destroys anything else covered by your
insurance, I would imagine.

If it's a good investment now then it doesn't really matter what
happens two years, two decades or two hundred years from now. How
stupid will you feel if they are more expensive two years from now?

What if a meteor wipes out all life on earth? How stupid will you feel
for planning on a future?

Entire systems are about as close to plug and play as they're ever going
to get. They've sell complete packaged systems these days. Some of the
thin film panels are getting pretty cheap and the power per sq. ft. is
quite sufficient (even at 5% efficiency) for most any purpose.

I'm not sure you would be first in line even if they paid you to take


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