For those who is also reading this thread, please advise me,

I need some advices as well, my builder of the new house is contracted with SunPower, and requires buyers to purchase SunPower panels installed.

The quote I got from builder is $12400 for a 3kW system, estimated 4200 kW annually production in my area (SoCal).

After 30% tax incentive, I will get 12400x 30% x 25% bracket = 930 cash back on the first year.

I did a good calculation determining the system is NOT a money saver at all and I won't get pay back in time.

Here is my calculation, $12400 added to a 30 years 4.5% mortgage rate itself, that's $63 monthly + SCE Edison $11 monthly net meter fee = $74 total monthly for next 30 years

Estimating my usage matches the productivity, no over usage that I have to buy from the grid, then $74 is what I pay with solar.

Now, 3kW system who generates 4200 kW an year (I live in SoCal area), then that's 350 kW a month.

(Assuming I don't use AC at any time of the year.) Without solar system, 350kW Tier 1 bill cost about $65 dollars from SCE Edison.

Please advise me if I did my calculation wrong, or simply the builder is over charging this system. Because every online information says the Solar system will pay back in 10~15 years.

But according to my own calculation, I won't get pay back till after 29 years.

I need some advices as well, my builder of the new house is contracted with SunPower, and requires buyers to purchase SunPower panels installed.

The quote I got from builder is $12400 for a 3kW system, estimated 4200 kW annually production in my area (SoCal).

After 30% tax incentive, I will get 12400x 30% x 25% bracket = 930 cash back on the first year.

I did a good calculation determining the system is NOT a money saver at all and I won't get pay back in time.

Here is my calculation, $12400 added to a 30 years 4.5% mortgage rate itself, that's $63 monthly + SCE Edison $11 monthly net meter fee = $74 total monthly for next 30 years

Estimating my usage matches the productivity, no over usage that I have to buy from the grid, then $74 is what I pay with solar.

Now, 3kW system who generates 4200 kW an year (I live in SoCal area), then that's 350 kW a month.

(Assuming I don't use AC at any time of the year.) Without solar system, 350kW Tier 1 bill cost about $65 dollars from SCE Edison.

Please advise me if I did my calculation wrong, or simply the builder is over charging this system. Because every online information says the Solar system will pay back in 10~15 years.

But according to my own calculation, I won't get pay back till after 29 years.

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