unclescrooge wrote: ↑
Tue Jul 10, 2018 5:52 pm
chazas wrote: ↑
Tue Jul 10, 2018 7:44 am
What technical problems did you face? Since there are zero moving parts in an electrical system, I have a had time understanding why there would be any issues after the initial burn-in period.
As a comparison, I spent $18k before 30% tax credit and save about $200-$300 per month.
How did this make mathematical sense?
How does it not ???
Let's see. $18K before 30% tax credit is $12,600 .
$200 per month (low end estimate) is $2400 per year.
So, the time to recoup the investment is 5.25 years, ie. 5 years and 3 months. That is a fairly short period of time.
And after that, the ROI is 2400/12600 ie. 19% . This is an after-tax return, also, since you would normally pay your electric bill with after-tax money.
This is not a guaranteed return. However, electricity prices tend to go up, not down. In some locales, there are regulations that make net metering less advantageous. Or simply rate changes that are less favorable to solar, like going from 5 tiers to 2 in California.
Last year, my solar system saved me $5,608.89 . This is the difference between my $1,177.77 actual bill, and the $6,950.93 bill I would have had without solar. The hypothetical bill without solar is calculated with a complex spreadsheet. If the bill sounds high, to put it in perspective, it includes enough electricity to drive about 28,000 electric miles between our two plug-in cars (one 100% EV, one plug-in hybrid). The rest is for the mansion with a hot tub, two air conditioner units, and lots more things. Everything is very efficient, but there is just a lot going on, and California electricity rates are quite high. Average would be about 27
36 cents/kWh without solar. This is based on 5556 kWh pulled from the grid, and 13,923 kWh produced by the solar system. The bill for 19,479 kWh on PG&E schedule E-1 in territory X would be $6,950.93 .
My solar system is fully amortized as of this January, meaning it has already paid back for the cost after tax credits, which was $32,239.80 .