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This is an encouraging milestone. Is it trivial at this point to figure out whether a solar home install is cost effective? ie plug in your address, your last

This is an encouraging milestone. Is it trivial at this point to figure out whether a solar home install is cost effective? ie plug in your address, your last 12 pg&e bills, and get a complete quote with a break down of time to profitability?

hackerlight 2y ago
Not trivial. Factors: Local labor costs, PV import tariffs, net metering arrangement, roof space and tilt angle, electricity prices, local solar irradiance levels, solar seasonality, and large cost difference between grid tie versus hybrid battery systems. If you live in a reasonably sunny country, the shorthand you can use is 4.5*(system size in KW), which equals the daily number of kWh your system will produce. Say that number is 30kWh. Then multiply 30 by your per kWh electricity costs. Say $0.2*30. That's your daily savings estimate, $6. Then you can figure out how many years to ROI by comparing it to the system cost. This approach will be more or less accurate if you have a battery or a nice net metering arrangement. It will be less accurate without either of these things.
nsriv 2y ago
I've used this and compared to friends who have installed solar, and it's been roughly accurate to +/- $1500 or so. https://sunroof.withgoogle.com/ https://sunroof.withgoogle.com/
- s1artibartfast 2y ago
  Sizing and cost for install seems wildly inaccurate for me in the bay area. Says a 2kw system will cover my needs and cost $8k to buy and install. Is it assuming I already have a huge battery or net metering?
  - coderatlarge 2y ago
    I've been frequently tempted by that tool but then when I go to try to take the next step I hit a bunch of complexity with installers. The Tesla experience is pretty good but seems to carry a huge markup.
    - s1artibartfast 2y ago
      Yeah, I put my contact info into one of the modeling websites thinking I would get a technical estimate, and not only did it not get it, they just sold my info ad now I get 3-5 spam calls a day. They all started as solar companies, but have branched out into general scams.

hackerlight 2y ago

Not trivial. Factors: Local labor costs, PV import tariffs, net metering arrangement, roof space and tilt angle, electricity prices, local solar irradiance levels, solar seasonality, and large cost difference between grid tie versus hybrid battery systems. If you live in a reasonably sunny country, the shorthand you can use is 4.5*(system size in KW), which equals the daily number of kWh your system will produce. Say that number is 30kWh. Then multiply 30 by your per kWh electricity costs. Say $0.2*30. That's your daily savings estimate, $6. Then you can figure out how many years to ROI by comparing it to the system cost. This approach will be more or less accurate if you have a battery or a nice net metering arrangement. It will be less accurate without either of these things.

nsriv 2y ago

I've used this and compared to friends who have installed solar, and it's been roughly accurate to +/- $1500 or so. https://sunroof.withgoogle.com/ https://sunroof.withgoogle.com/

s1artibartfast 2y ago
Sizing and cost for install seems wildly inaccurate for me in the bay area. Says a 2kw system will cover my needs and cost $8k to buy and install. Is it assuming I already have a huge battery or net metering?
- coderatlarge 2y ago
  I've been frequently tempted by that tool but then when I go to try to take the next step I hit a bunch of complexity with installers. The Tesla experience is pretty good but seems to carry a huge markup.
  - s1artibartfast 2y ago
    Yeah, I put my contact info into one of the modeling websites thinking I would get a technical estimate, and not only did it not get it, they just sold my info ad now I get 3-5 spam calls a day. They all started as solar companies, but have branched out into general scams.