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Plan for future usage: EV, heat pump, ADU

Cali-Graf calculates from the home’s past usage and doesn’t add future loads on its own. If the customer is getting an electric car, a heat pump or an ADU, add your estimate of the extra kWh to the usage before you calculate.

Sizing the system only for last year’s bills leaves a customer who buys an electric car next month short of solar. If you know about new loads, put them in the usage now.

Add the extra usage

  1. Estimate the extra kWh a year

    For an electric car: miles driven a year divided by the car’s miles per kWh (most cars do 3 to 4). For a heat pump, an ADU or a pool, use the equipment’s specs or the installer’s estimate.

  2. Add it to the usage

    The simplest way: open Usage, pick Yearly total and enter last year’s total plus the extra kWh. To keep the customer’s own seasonal shape, stay on Bills and add a share of the extra to each bill instead.

  3. Check the system size

    After Calculate, look at how much of the usage the panels cover. Add panels in the roof editor if needed.

Things to keep in mind

  • The extra kWh follow the typical pattern of the home’s usage, not the new device’s schedule. An electric car charging at night is closer to reality on SCE’s TOU-D-PRIME — but pick the plan the customer is actually on today.
  • The bill “today” in the result includes the extra usage, so it’s higher than the customer’s current bills. Explain that the comparison is for the home with the new load.
  • For LADWP homes, solar beyond the home’s yearly usage isn’t paid for — don’t size for loads that may never come.

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