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    Second Tesla Powerwall · ACT 2600

    A second battery, and the first one fixed

    Sunstak added the second battery to a system another company had installed a year earlier.

    Two white Tesla-badged batteries standing side by side against a board-formed concrete retaining wall on a paved terrace, with ornamental grasses along the top of the wall and trees behind

    What the customer wrote

    Sunstak have just added a second Tesla Powerwall battery to my system, which had been installed a year ago by another provider. … The quality and professionalism of the installation was particularly impressive. Several deficiencies in the installation of the existing battery by my previous supplier were rectified without cost or question, even though some were not apparent at the time of quoting.
    Peter5 out of 5.Published on SolarQuotes

    System specifications

    Battery
    Tesla Powerwall 3
    Battery capacity
    27 kWh, two units
    Existing battery
    Fitted a year earlier by another provider
    Rectification
    Previous supplier's defects, no charge

    About this job

    Taking on someone else's install

    An installer who connects to existing work owns the result. That means checking isolation, labelling, cable sizing, mounting and protection on the equipment already there before adding to it. Most of it can be assessed at quoting. Some cannot, because it is behind a cover or inside a switchboard that stays live until the day. The alternative is refusing the job.

    Defects found after the quote

    Faults that appear on install day are a commercial problem as much as a technical one. Someone pays: the customer through a variation, or the installer out of the job. On this one the deficiencies in the earlier battery install were corrected without a charge or an argument, including the ones nobody could have seen at quoting.

    Two batteries, one system

    A second battery is not a spare. Both units share the same backup circuits and the same gateway, and they have to be commissioned as one so charge and discharge are coordinated. Get that wrong and the household has twice the hardware with no more useful backup. Get it right and the app shows one system, which is all the owner should ever have to think about.

    How we work

    The job above ran the way every Sunstak job runs. Six steps, from the bill you send us to the day your system is switched on.

    1. A cyan sign board standing on a driveway, lettered sunstak above the words THIS HOUSE IS POWERED BY SUNSTAK with the address sunstak.com.au along the bottom, the front of a white car in the left foreground and timber steps with two orange traffic cones behind it

      Before the visit

      Send us two bills, one from summer and one from winter, and tell us roughly when your house is busy. Your own numbers are where the design starts.

    2. Two men reaching to shake hands on the front path of a brick house with solar panels on its roof, one of them in a dark t-shirt carrying a circular cyan mark, while a woman stands in the open front doorway behind them

      Site visit or phone consultation

      One of our energy geeks goes through the roof, the switchboard and the meter with you, at the house or over the phone. What goes where, what the roof can carry and whether the board has room all get settled here.

    3. Two people at a desk in an office, one pointing at a wide monitor showing an aerial view of a house with a solar panel layout drawn on its roof

      Customised design

      A Sunstak engineer designs the system in house. You get back a drawing of your own house with the equipment set out on it, and what decided where each piece went.

    4. A man at a timber desk holding a telephone handset to his ear, two monitors in front of him showing an aerial view of rooftops and a bar chart, beside a keyboard, an open notebook and a mug

      Quote approval

      Your quote lists every item with its model number, and the exclusions as plainly as the inclusions. There is nothing to sign on the day, and nothing is ordered until you approve it.

    5. A person standing on a tiled roof holding a large solar panel above their head against a blue sky, with another person's hand reaching up from the gutter below

      Installation

      We tell you up front what gets switched off on the day, and for how long.

    6. A single-storey timber-clad house on a dry rural block at golden hour, its pitched metal roof covered by a full array of solar panels, a white battery standing against the timber wall beside a car charger with its cable coiled, a dark grey car parked on the gravel driveway and gum trees and low hills behind

      Post-installation support

      Nobody leaves until the system is commissioned and the monitoring is running on your phone. After that, service and warranty go through the same office that did the install.

    More of the work

    Every one of them is a customer's own account of the job.

    All projects

    • Tesla Powerwall 3 ACT 2906

      The spot stayed, the battery changed

      The standards decide where a battery can sit: clearances, the wall behind it, and the run back to the switchboard. Here the position the owner wanted stayed, and the battery changed to one rated to live outdoors. A plumber capped a disused gas line on the same visit.

      Everything was smooth from the initial quote, through to the installation. There was some initial back and forth about which type of battery to install and location. In the end my preferred location was not going to meet standards which then meant having to change the brand of battery to one that would be more suitable outdoors. This was all handled well by Michael and the team.
      Steve SolarQuotes
      Battery
      Tesla Powerwall 3
      Battery capacity
      13.5 kWh
      Siting
      Rated for outdoors
      On the day
      Plumber capped a gas line
      A single white Tesla-badged battery mounted on the grey rendered wall of a house, beside a timber-clad corner and a tall narrow window, standing on a pale timber deck in hard sunlight

    • Battery retrofit ACT 2905

      Quoted after looking at the house

      Retrofitting storage to an existing array depends on things you can only see on site. The inverter already fitted, spare ways in the switchboard, where a battery can legally sit, and how far that is from the meter. Some of the companies asked to quote this job never visited the house.

      I reviewed all of the companies on the ACT Government approved list for a solar battery to add to my existing solar panel system. I sought quotes from the 6 best rated companies. From the 4 quotes I received I chose SunStak. The main reason I chose them was because they were the most responsive, helpful and reasonably priced, a couple of the others didn't even visit the house before quoting.
      Berceuse SolarQuotes
      Work
      Battery added to an existing array
      Approved list
      ACT Government battery scheme
      Quotes sought
      Six approached, four quoted
      Site visit
      Some competitors quoted without one
      A white Tesla home battery mounted on dark blue weatherboard beside an open door, with two people talking at a table inside the lit room

    • Commercial rooftop solar Wanniassa ACT

      A school hall in Wanniassa

      A school roof is a set-out problem with a deadline attached. The array had to be planned, delivered and commissioned inside the break before the new term, on a site coordinated by somebody else. Forty kilowatts of panels onto one long hall roof, in five days, with six people on it.

      Thank you for delivering this project before the start of a new school term
      Project Manager, Trinity Christian School Sunstak Capability Statement, July 2025
      Panels
      Trina Solar
      Inverter
      30 kW Sungrow commercial
      Solar
      40 kW
      On site
      Five days, six staff
      Overhead aerial view of four long rows of solar panels on the curved-ridge roof of a large school building, with a playground and a yellow climbing frame in the yard alongside

    • Commercial solar and battery Lyneham ACT

      A temple in Lyneham

      The temple was referred by community members worried about its power bills: a large, draughty, hard-to-heat complex. Twenty kilowatts of solar and a forty-kilowatt-hour battery, with the meter board upgraded to carry it. The battery is there to hold the peak down, which on a commercial tariff is a separate charge from the energy.

      The Abbot is very pleased and wishes to pass on his appreciation and support to get this project delivered
      Project Manager, Wat Dhammadharo Sunstak Capability Statement, July 2025
      Solar
      20 kW
      Battery
      Three Tesla Powerwall 3
      Battery capacity
      40.5 kWh
      Switchboard
      Meter board upgraded
      Aerial view of solar panels across the tiled roof of a long brick building, with a spire-roofed hall beside it and gilded temple roofs among trees behind

    Start saving with Sunstak

    Speak with one of our energy geeks today.

    • Tesla Powerwall Premium Certified Installer
    • New Energy Tech Consumer Code approved seller
    • SunWiz 2026 award: Best Rated solar installer, #2 Most Popular in the A.C.T.
    • Solar Accreditation Australia approved

    ★★★★★

    Having used two other installers previously, the Sunstak experience is head and shoulders superior…
    Raffaele WebbGoogle review
    • 4.9From 216 Google reviews
    • 5.0From 29 SolarQuotes ratings

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