Solar panels in Mount Gambier

Mount Gambier averages 5 peak sun hours a day and sits in STC Zone 3. A peak sun hour is an hour of sunlight at full strength, so the figure is what a panel collects once the weaker morning and evening light is added up. On that average, this is what the two most common system sizes produce on a north-facing roof with no shade.

Worked as system size times 5 peak sun hours times 85%, the allowance our suburb pages make for inverter, heat and wiring losses, over 365 average days. Summer days produce well above the average and winter days well below it, and an east or west-facing array produces less than a north-facing one.

Across the eight capitals, the same 6.6 kW system makes from about 7,576 kWh a year in Hobart to about 11,262 kWh in Darwin. In Mount Gambier it makes about 6% more than it would in Adelaide. More sun means more output from the same panels, but it does not change the STC rebate within a zone: that is set by the zone, the system size and the year you install.

These are the installed prices our solar panel cost guide works on, with the federal STC rebate for Mount Gambier taken off. The rebate comes off the quote at the point of sale, so the last column is what you actually pay. In STC Zone 3 it is worth $1,710 on a 6.6 kW system and $2,622 on a 10 kW one.

• 5 kW

  Installed price

  $4,500 to $6,500

  STC rebate, Zone 3

  $1,292

  You pay after the STC

  $3,208 to $5,208

• 6.6 kW

  Installed price

  $5,500 to $8,000

  STC rebate, Zone 3

  $1,710

  You pay after the STC

  $3,790 to $6,290

• 10 kW

  Installed price

  $8,000 to $12,000

  STC rebate, Zone 3

  $2,622

  You pay after the STC

  $5,378 to $9,378

• 13 kW

  Installed price

  $10,000 to $15,000

  STC rebate, Zone 3

  $3,382

  You pay after the STC

  $6,618 to $11,618

Prices are the national ranges from our solar panel cost guide. Installed prices are before any rebate. The STC rebate is the certificates each system creates in Zone 3 over the 2026 deeming period of 5 years, at $38 a certificate. The deeming period shortens by a year every 1 January, so the same system earns less rebate each year you wait.

The average system installed across Mount Gambier in the 12 months to October 2026 was 11 kW, between the 10 kW and 13 kW rows, although that average includes some business systems. Size yours on your own bills and roof, but it is a fair check on what your neighbours are putting up.

What moves a quote up or down: the panel and inverter brands, a second storey or a steep or tiled roof, and switchboard or meter work. The full breakdown is in our solar panel cost guide.

The federal Cheaper Home Batteries rebate applies in Mount Gambier as it does everywhere. It is paid on usable capacity, at $258/kWh for the first 14 kWh and at lower rates above that, and like the STC rebate it comes off the price at the point of sale. It steps down on 1 January 2027, when the full rate falls to $217/kWh.

The table is the federal rebate only: there is no SA battery rebate that a typical household can count on.

South Australia: VPP incentives. The SA Home Battery Scheme has closed.

Whether a battery pays in Mount Gambier comes down to the gap between what you pay for power and what you are paid for exporting it. Each kWh a battery moves from export into your evening is worth about 30.0c (42.0c less 12.0c). A 10 kWh battery that filled and emptied every day would be worth up to $1,095 a year on that gap alone; most do less in winter, when there is less surplus to store.

Battery prices by size, before and after the federal rebate, are in our battery cost guide, and the SA battery rebate page has the state detail.