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Saturday, January 12, 2013

A Great Investment


The numbers are in:  we are doing way better on the return from our solar PV system than we are at the bank.

Here are the results in Steve's own words:

"We used 4638.92 kWh of electricity for the 12 months November 2011 through November 2012. We produced 5261.92 kWh in the same time period, meaning that our solar system covered all of our electrical needs.

If we had needed to buy the 4638.92 kWh from PGE at 13.56 cents/kWh, it would have cost $628.81. Subtracting out our connection fees and taxes for using PGE as our battery, the value to us is $505.69.

Our return on investment is the value of the electricity divided by the cost to us of the system. $505.69 / 7492.5 = 6.75%

We will not truly know if our system was sized correctly until the end of March when any excess credits are transferred to the low income assistance fund."

We could have opted for the program whereby our local utility would cut us a check for the excess of what we produce, but that would have meant a minimum of a 6 kWh system, and we would have needed a larger roof for that which would mean a bigger house, which would have resulted in a higher mortgage payment, which would have pretty much defeated the purpose.  I am just fine with what we have- we pay $10.26 a month to be hooked up to PGE, which we use as a giant battery, and any excess produced will be donated to the low income assistance fund at the end of PGE's period in March.  I doubt we would go off grid until we're out in the country (which is back on the table - Yay!) at which point we'd be working with a low-voltage system anyway.

As it is, our electricity costs for the entire year is only $123.12. If we're careful and continue to at least use the same or less electricity  than we produce, they will always be only $123.12 for the entire year, until such time as PGE sees fit to raise the cost of being connected to the grid, of course, which will reduce what goes to the low income assistance fund.

I wish I could do that well with the natural gas bill.  The only thing that makes that spike is if Steve brews beer.  Last month's gas bill was a whopping $31.13 and I'm sincere about whopping because the month previous it was in the $25 range.  In the summer we use almost zero natural gas because we don't cook indoors and that is the period when the solar water heater is rockin' the hot water.


By the way, this is all happening in the Pacific Northwest, where the only thing thicker than the persistent mist that falls almost three quarters of the year is the abundant moss growing on everything.

If we can do it, you can do it, so if you're thinking about solar and can afford it, do it.  Part of what made this work for us is the fact that we saved up and paid cash for it, but if your results were the same as ours and you borrowed at 3% for it, you'd still be ahead.

It would still be a great investment.
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