Estimated PV payback with accelerated mortgage payoff and savings from new meter
      California Income Tax Rate   Assumed Federal Tax Rate            
      9.30%   25%            
Year Regular Mortgage Payments Interest Paid CA tax mortgage deduction Interest - CA deduction -15% CA tax credit Federal Tax Deduction Net Cost of Loan PV Savings Cash Flow PV Estimated Savings from New Meter Cash Flow PV and New Meter End of Year Mortgage Principal
1 $3,758.27  $3,062.85  $ 284.85  $ 2,778.00  $    694.50 $2,778.92 $2,009.73 ($769.19) $2,692.66 $1,923.47  $40,315.11
2 $3,006.61  $2,299.69  $ 213.87  $(5,442.18)  $(1,360.55) $4,153.29 $1,827.80 ($2,325.49) $2,439.40 $113.91  $39,494.27
3 $2,544.17  $1,961.46  $ 182.42  $ 1,779.04  $    444.76 $1,916.99 $2,675.01 $758.02 $2,460.95 $3,218.97  $35,692.60
4 $2,544.17  $1,766.99  $ 164.33  $ 1,602.66  $    400.66 $1,979.17 $3,761.58 $1,782.41 $2,686.47 $4,468.88  $30,446.54
5 $2,544.17  $1,498.59  $ 139.37  $ 1,359.22  $    339.81 $2,064.99 $3,761.58 $1,696.59 $2,686.47 $4,383.06  $25,017.90
6 $2,544.17  $1,220.85  $ 113.54  $ 1,107.31  $    276.83 $2,153.80 $3,761.58 $1,607.78 $2,686.47 $4,294.25  $19,400.33
7 $2,544.17  $   933.44  $   86.81  $    846.63  $    211.66 $2,245.70 $3,761.58 $1,515.88 $2,686.47 $4,202.36  $13,587.25
8 $2,544.17  $   636.04  $   59.15  $    576.89  $    144.22 $2,340.79 $3,761.58 $1,420.79 $2,686.47 $4,107.26  $  7,571.86
9 $2,544.17  $   328.27  $   30.53  $    297.74  $      74.44 $2,439.20 $3,761.58 $1,322.38 $2,686.47 $4,008.85  $  1,347.12
10 $2,544.17  $     21.10  $    1.96  $      19.14  $       4.78 $2,537.42 $3,761.58 $1,224.16 $2,686.47 $3,910.63  Paid off
11+ $0.00 $0.00 $3,761.58 $3,761.58 $2,686.47 $6,448.05
Assumptions about mortgage amount and interest rates are detailed in the Mortgage tab.
In this analysis, the cash flow from the PV and meter is used at the end of the year to pay down the mortgage faster.
Numbers in blue represent assumption that future year savings will be same as current year savings.
Federal tax deduction in year two is negative because we had to pay Federal income tax on the 15% tax credit that we got from California.
New Meter Savings assumes that if we still had the old meter, that it would continue to read a usage of 80 KWH/day.
When the new meter was put in, the new meter read a usage 46% lower than the old meter (independent of the PV array).
We suspect the old meter read Volt-Amperes and the new meter reads Watts
and that the difference is caused by the Power Factor from the inductive loads of the computers.