How Much Energy Can a Solar System Generate Per Day?
One of the most common questions homeowners ask when considering solar is: how much energy will my system actually produce each day? The answer depends on several factors, including system size, your location, and how much sunlight your roof receives. Let’s break it down with real examples relevant to Australian homes.
Understanding Solar System Output
Solar panels are rated in kilowatts (kW), which indicates the maximum amount of power they can generate in ideal conditions. A 6.6 kW solar system, for example, can theoretically produce 6.6 kilowatts of electricity per hour of full sun.
However, in reality, the amount of energy generated is measured in kilowatt-hours (kWh), and this depends on how many hours of effective sunlight the panels receive each day.
Sunlight Hours in Australia
Australia is blessed with abundant sunshine, making it one of the best countries in the world for solar. On average:
Sydney receives around 4.5 hours of peak sun per day.
Brisbane enjoys about 5.0 hours.
Perth leads with roughly 5.5 hours.
Melbourne averages closer to 4.0 hours.
These “peak sun hours” are the key to calculating your daily solar output.
Example: 6.6 kW Solar System
Let’s look at an example using a common residential solar system size.
Sydney: 6.6 kW × 4.5 sun hours = 29.7 kWh per day
Brisbane: 6.6 kW × 5.0 sun hours = 33 kWh per day
Perth: 6.6 kW × 5.5 sun hours = 36.3 kWh per day
Melbourne: 6.6 kW × 4.0 sun hours = 26.4 kWh per day
For context, the average Australian household uses around 18–20 kWh of electricity per day. This means that even in Melbourne, a 6.6 kW system can more than cover typical daily usage, with extra power available for storage or export back to the grid.
Scaling Up: Larger Solar Systems
If you have higher energy needs, perhaps due to a larger home, air conditioning, or an electric vehicle, bigger systems provide even more savings.
For example, a 10 kW system in Brisbane would generate about:
10 kW × 5 sun hours = 50 kWh per day
This can easily cover a large household’s needs and support battery storage for night-time use.
Why Your Results May Vary
It’s important to note that output is influenced by:
Roof orientation and tilt – north-facing panels in Australia capture the most sunlight.
Shading – trees, chimneys, or nearby buildings can reduce output.
Seasonal changes – longer summer days boost production, while winter days reduce it slightly.
On average, Australian solar systems generate between 4 and 5 kWh per day for every kilowatt of installed capacity. That means a 6.6 kW system produces roughly 26–36 kWh daily, depending on location.
By choosing the right system size for your household and factoring in your city’s sunlight hours, you can get a clear picture of your potential savings and energy independence.
Get in touch today to start our journey together.
Stay committed!
Damien Frearson
