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I just had my panels turned on. I love solar. It's still difficult to justify it short-term on a cost-basis, but I'm saving about a dollar a day after all thing

I just had my panels turned on. I love solar. It's still difficult to justify it short-term on a cost-basis, but I'm saving about a dollar a day after all things are said and done. That being said, I'm generating my own electricity and my panels will run for a very long time. The best is cranking the AC and still watching the meter run in reverse during really scorching days.

fred_is_fred 9y ago
What the NPV and pay-off time of your system? I've been unable to get one bid here that's less than 10 years because electricity is fairly cheap here.
- matt_wulfeck 9y ago
  Yes it's 10 years for me as well. Most of that is because we have a 30% efficiency hit because we didn't want to cut down a tree in our backyard that shades it for 2 hours a day during about 6 months of the year. Our system is also larger than our current usage, because we plan to use more (electric car, more kids, etc). Another benefit to think about is you've effectively locked in your electricity rate. With some companies that might not be a big thing, but here in CA PG&E has been relentless with their rising kwh costs.
  - fred_is_fred 9y ago
    I pay on average about 10.3 cents per kwh and have a newer home that's very efficient at holding cool air (and live in a state where we heat more than we cool). For those reaons it's a tough sell for me. If rates continue to rise and solar continues to fall, we'll have a cross over that works for me probably in a few years.
    - matt_wulfeck 9y ago
      It's not cost competitive for you at 10 cents. Why bother? I'd kill for that kind of price in electricity. Our total cost with solar is around 13c per kwh over 20 years.
      - wilwade 9y ago
        I also have the same (10.7 cents over the past year). We have a community solar project in town, but it is ~13 cents over 20 years as well.
      - fred_is_fred 9y ago
        That's also what SolarCity told me...
    - ianai 9y ago
      Any chance some of your energy comes from nuclear?
      - fred_is_fred 9y ago
        Coal and wind. I live in Colorado.
    - Spooky23 9y ago
      You're in a good place. I live in a neighborhood with older homes similar climate. Lots of people are doing solar because it's cool, but ignoring windows and insulation. We ran the numbers on our house with an energy audit and found that the return on insulation, an attic fan and window replacement was literally like 2-3x solar. The other thing to look at is solar hot water. It's not sexy, but that has been high ROI since the 80s.
- e40 9y ago
  For the one I'm about to install it is little over 5 years.
- workerIbe 9y ago
  I have built a system that cost just under $2k and should pay off in about 3-4 years (depending on battery lifetime). 2.4 Kw (8 panels) of used panels @ $.32/Watt, Charge controller, 3Kw inverter, transfer switch and 320ah@48v used Golf Cart Batteries. System is offgrid and supplies all my convenience outlets, kitchen and 240v circuits are on still on the grid. Panels are on top of free standing structures and being off grid permits are not required and only the transfer switch installation needed to be done by an electrician. Bonus is being offgrid it acts as a big UPS in a power failure.
  - matt_wulfeck 9y ago
    This is a great plan. PG&E here in California forces solar customers onto a more expensive plan. If you can avoid that switch and use solar to dramatically reduce (but not eliminate) your total kwh load then you'll definitely come out way ahead, because you'll be on their cheapest tier.
    - workerIbe 9y ago
      Yes, most of the electricity I have generated has been what would have been tier 2 @ $.26 kWh, with the climate stuff going thru Sacramento atm I expect the price to go even higher soon.
    - njarboe 9y ago
      California will be changing dramatically how it charges for electricity in the next few years[1]. I was talking to a person Tesla today about putting solar on our house and he mentioned in passing that Time-Of-Use Rates will be the default for everyone in California in 2019 by law (AB 327 in passed in 2013). For your net metering you will get credit/pay for power to/from the grid at the rate for the time it happens. A good up-sell for the powerwall. If the rates get way out of wack due to high solar input, one could do well charging your powerwall during the peak solar production hours (see duck curve [2]) and putting them back on the grid a 3-6 hours later. [1] https://cleantechnica.com/2015/06/08/california-rolls-out-default-time-of-use-rates/ https://cleantechnica.com/2015/06/08/california-rolls-out-de... [2] http://instituteforenergyresearch.org/solar-energys-duck-curve/ http://instituteforenergyresearch.org/solar-energys-duck-cur...
- lutorm 9y ago
  The pay off time for our system here in Hawaii was, if I recall, about 6 years, even though the price of installations is really high. The price of electricity is too, though.
  - matt_wulfeck 9y ago
    What do you pay per kwh?
    - vkou 9y ago
      The internet tells me it's 30c/KWH. Hawaii's primary source of electricity is oil.
- fovc 9y ago
  I'm assuming a 10 year payback equates to an annualized return of ~7%. Would you be paying cash for the panels or using financing? If the former, do you have other investments paying that much? If the latter, at what interest rate?
  - matt_wulfeck 9y ago
    Right now it's a 20 year loan at 5%, $106 a month, but we're going to pay 50% of it cash and 50% HELOC for tax deduction purposes. There's a 30% tax deduction one time for the total cost. My loan payment is less than my precious monthly power costs including taxes and fees ($15 a month to be hooked up to PG&E).
- Spooky23 9y ago
  Remember to look at other below the line costs too... particularly with leasing there are cases where the homebuyers credit situation can make selling your home difficult. One friend had to take a hit in the selling price as a concession to buyout part of the lease.

fred_is_fred 9y ago

What the NPV and pay-off time of your system? I've been unable to get one bid here that's less than 10 years because electricity is fairly cheap here.

matt_wulfeck 9y ago
Yes it's 10 years for me as well. Most of that is because we have a 30% efficiency hit because we didn't want to cut down a tree in our backyard that shades it for 2 hours a day during about 6 months of the year. Our system is also larger than our current usage, because we plan to use more (electric car, more kids, etc). Another benefit to think about is you've effectively locked in your electricity rate. With some companies that might not be a big thing, but here in CA PG&E has been relentless with their rising kwh costs.
- fred_is_fred 9y ago
  I pay on average about 10.3 cents per kwh and have a newer home that's very efficient at holding cool air (and live in a state where we heat more than we cool). For those reaons it's a tough sell for me. If rates continue to rise and solar continues to fall, we'll have a cross over that works for me probably in a few years.
  - matt_wulfeck 9y ago
    It's not cost competitive for you at 10 cents. Why bother? I'd kill for that kind of price in electricity. Our total cost with solar is around 13c per kwh over 20 years.
    - wilwade 9y ago
      I also have the same (10.7 cents over the past year). We have a community solar project in town, but it is ~13 cents over 20 years as well.
    - fred_is_fred 9y ago
      That's also what SolarCity told me...
  - ianai 9y ago
    Any chance some of your energy comes from nuclear?
    - fred_is_fred 9y ago
      Coal and wind. I live in Colorado.
  - Spooky23 9y ago
    You're in a good place. I live in a neighborhood with older homes similar climate. Lots of people are doing solar because it's cool, but ignoring windows and insulation. We ran the numbers on our house with an energy audit and found that the return on insulation, an attic fan and window replacement was literally like 2-3x solar. The other thing to look at is solar hot water. It's not sexy, but that has been high ROI since the 80s.
e40 9y ago
For the one I'm about to install it is little over 5 years.
workerIbe 9y ago
I have built a system that cost just under $2k and should pay off in about 3-4 years (depending on battery lifetime). 2.4 Kw (8 panels) of used panels @ $.32/Watt, Charge controller, 3Kw inverter, transfer switch and 320ah@48v used Golf Cart Batteries. System is offgrid and supplies all my convenience outlets, kitchen and 240v circuits are on still on the grid. Panels are on top of free standing structures and being off grid permits are not required and only the transfer switch installation needed to be done by an electrician. Bonus is being offgrid it acts as a big UPS in a power failure.
- matt_wulfeck 9y ago
  This is a great plan. PG&E here in California forces solar customers onto a more expensive plan. If you can avoid that switch and use solar to dramatically reduce (but not eliminate) your total kwh load then you'll definitely come out way ahead, because you'll be on their cheapest tier.
  - workerIbe 9y ago
    Yes, most of the electricity I have generated has been what would have been tier 2 @ $.26 kWh, with the climate stuff going thru Sacramento atm I expect the price to go even higher soon.
  - njarboe 9y ago
    California will be changing dramatically how it charges for electricity in the next few years[1]. I was talking to a person Tesla today about putting solar on our house and he mentioned in passing that Time-Of-Use Rates will be the default for everyone in California in 2019 by law (AB 327 in passed in 2013). For your net metering you will get credit/pay for power to/from the grid at the rate for the time it happens. A good up-sell for the powerwall. If the rates get way out of wack due to high solar input, one could do well charging your powerwall during the peak solar production hours (see duck curve [2]) and putting them back on the grid a 3-6 hours later. [1] https://cleantechnica.com/2015/06/08/california-rolls-out-default-time-of-use-rates/ https://cleantechnica.com/2015/06/08/california-rolls-out-de... [2] http://instituteforenergyresearch.org/solar-energys-duck-curve/ http://instituteforenergyresearch.org/solar-energys-duck-cur...
lutorm 9y ago
The pay off time for our system here in Hawaii was, if I recall, about 6 years, even though the price of installations is really high. The price of electricity is too, though.
- matt_wulfeck 9y ago
  What do you pay per kwh?
  - vkou 9y ago
    The internet tells me it's 30c/KWH. Hawaii's primary source of electricity is oil.
fovc 9y ago
I'm assuming a 10 year payback equates to an annualized return of ~7%. Would you be paying cash for the panels or using financing? If the former, do you have other investments paying that much? If the latter, at what interest rate?
- matt_wulfeck 9y ago
  Right now it's a 20 year loan at 5%, $106 a month, but we're going to pay 50% of it cash and 50% HELOC for tax deduction purposes. There's a 30% tax deduction one time for the total cost. My loan payment is less than my precious monthly power costs including taxes and fees ($15 a month to be hooked up to PG&E).
Spooky23 9y ago
Remember to look at other below the line costs too... particularly with leasing there are cases where the homebuyers credit situation can make selling your home difficult. One friend had to take a hit in the selling price as a concession to buyout part of the lease.