What size solar system do I need in the Australian Capital Territory?
Size follows your bill and your usage, not your roof area. In Australian Capital Territory, at 37c a unit, a household on a $605 quarterly bill is using around 15 kWh a day and wants roughly 10–13kW solar.
What is different about the Australian Capital Territory
At 37c a unit the Australian Capital Territory sits 2nd of 8 on retail price, with a feed-in tariff of 2c. It averages 4.7 peak sun hours a day.
By household, in the Australian Capital Territory
| Household uses | Their bill a quarter | System | After rebates | Saves a year | Pays for itself |
|---|---|---|---|---|---|
| 10 kWh | $437 | 6.6kW solar | $6,250 to $8,250 | $490–$740 | 10+ years |
| 15 kWh | $605 | 10–13kW solar | $8,000 to $13,000 | $770–$1,160 | 8–10+ years |
| 22 kWh | $841 | 10–13kW solar | $8,000 to $13,000 | $1,020–$1,530 | 6–10 years |
| 30 kWh | $1,110 | 10–13kW solar | $8,000 to $13,000 | $1,290–$1,940 | 5–8 years |
The bill column is what that household pays here at 37c a unit.
Why bigger is not automatically better
Every extra panel generates more, but the extra generation is only worth 37c if you are home to use it and 2c if you are not. In a state with a 2c feed-in rate, a system sized well past your daytime consumption is producing power worth almost nothing for most of its output.
That is the real limit on sizing here, and it is why the honest answer depends on occupancy. The same 15 kWh household saves $940–$1,390 home most days and $640–$950 out all day, on the identical system.
Things that legitimately push you bigger
An electric car, which adds about 4.8 to 9 kWh a day. A pool pump, which is a large load you can run in the middle of the day. Electric hot water on a daytime cycle. Moving off gas. All of them raise daytime consumption, which is the only thing that makes extra capacity pay.
Roof space is rarely the constraint. A 6.6kW array is about 15 to 16 panels and fits on most single-storey roofs. If an installer leads with how many panels will fit rather than what you use, that is a sizing conversation running backwards.
$5,000 difference.
That is the gap between two quotes for the same 6.6kW system in the Australian Capital Territory, in the same week. Not build quality, not a better job. Overheads, how full the diary is that month, and what the person at your kitchen table thinks you will agree to. On solar with a battery the same gap is $10,600.
Closing that gap is what I do. I already know what installers in your area are quoting this month for this equipment, so I get you the bottom of that range for the same system other companies charge thousands more for. It costs you nothing. The installer pays me, and only if you go ahead, which is why there is no reason for me to push you at a bigger system than you need or at a dearer installer.
Get your own numbers, then get them priced properly
The table above is four example households. Two minutes of questions gets you your system size, what it should cost after rebates in the Australian Capital Territory, and a ten-year projection built on your roof and your usage. Then I find the bottom of that price range for you.
Run my numbers, freeNo installer buys placement or ranking here, and nothing reaches an installer unless you ask.
Common questions
What size solar system do I need in the Australian Capital Territory?
A household on a $605 quarterly bill, using about 15 kWh a day, wants roughly 10–13kW solar. Larger bills move up from there.
Is a bigger solar system always better?
No. Extra generation you are not home to use is worth only 2c a unit in Australian Capital Territory, against 37c for power you use as it is made.
What makes a bigger system worth it?
Daytime load. An EV, a pool pump, electric hot water on a day cycle, or someone home during the day.