Solar and Battery System on Contact Energy Good Nights Plan

miso on 22/09/2023 - 15:02
Last edited 22/09/2023 - 15:39 by 1 other user

I am currently looking into getting a solar with battery system on the Contact Energy Good Nights Plan, are there anyone out there doing the same?

During the day I am hoping to sell the excess energy that the house is not using from solar back to the grid, between 9pm to 12, charge up the battery to use overnight hoping that it will cover the energy consumption till the sun rises in the morning. If you are doing similar, what system are you using? Huawei, Tesla or others? What is your experience like using the system, i.e. how is the software side of things? Thank you!

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  Wakrak on 22/09/2023 - 15:55

  +2

  Might get some good feeback on Geekzone

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  joem on 22/09/2023 - 19:05

  +1

  Huawei user here. I have a 10kW battery, a 5Kw inverter and 6.9kW in panels.
  I am on Contact Energy Good Nights Plan, pretty happy with it.

  I am controlling the charging/discharging via Home Assistant, but it can be done directly in the Huawei fusion solar app.

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    miso on 22/09/2023 - 22:38

    How much did you spend for the system if you don't mind me asking. Does the 10kw battery get you through the night?

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      joem on 22/09/2023 - 23:04

      +1

      We've spent ~33.000 for the whole system last November.
      The 10kW battery lasts through the night. At ~6:30 in the morning the state of charge is still around 35-40%, but it depends of the situation, temperatures, etc. I am in Invercargill. The power of the house during the night is ~400-450Wh.

      During winter I set Battery End-of-charge to 95%, while in the summer I lower it to be around 85-90%, depending of the weather forecast. End of discharge is se to 15%.

      My strategy:
      - charge the battery from the grid between 21-00 and heat the house to around 23C-24C degrees (depending on how cold the night is going to be)
      - in case the temperature in the bedroom drops below 18C, the heat pump (ducted) kicks in to maintain the temperature at 18C. Usually the wake up time is at 6:45
      - the water in the hot water cylinder is usually set to be heated only between 21-00, but in case the solar forecast for the next day is good, the HWC power supply is not going to be turned off for the night and next day

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        phillq on 23/09/2023 - 07:33

        +2

        Mine was 15k for a 10kWh battery, 5kW inverter and 3kW of solar.
        I worked out that if I instead invested in Tesla stock, it would have been WAY better value in terms of money made, and faster return on investment.

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  HighvoltageRuss on 25/09/2023 - 15:08

  I have a solar system without a battery as we have someone home most of the day to make use of what is generated. Plan to get a battery added on in the future.
  I wouldn't get a solar system with the idea that the good nights plan is going to stay around long term though it may do. Will it still work for you If the plan is ended and no longer available.