Over 1.5 million of Australians now live under solar rooftops. Household solar systems vary in their capacity and the number of solar panels that they use. So how do you figure out how many solar panels do you need for your home?
Every solar photovoltaic (PV) system has a certain number of panels, but system size is not usually discussed in terms of the number of panels used. This is because not all solar panels are created equal: some will produce more energy than others.
The amount of energy that a panel can produce in a given location is a function of both panel size (i.e. the square meter area of the panel) and its efficiency (i.e. how effectively can it convert sunlight into usable energy). Combined, these two factors equate to a panel’s ‘capacity’, which is usually described in kilowatts (often written as kW).
Panels from about five years ago tended to be both smaller in size and less efficient than modern-day panels. Similarly, the capacity of solar PV systems from this period also tended to be on the small side by today’s standards, at around 1.5 – 2 kW as opposed to 3 – 5 kW. An older 2 kW system, for example, usually contained more panels (around 10 – 12) than a modern 2 kW system (around 8-10.)
The table below gives some examples of how solar systems of the same capacity could contain a different number of panels. (N.b. 1 kW equals 1000 watts, W.)
|System capacity||Number of panels (at 200 W per panel)||Number of panels (at 250 W per panel)|
This shows that it’s more meaningful to talk about solar power in terms of capacity instead of the number of panels. A capacity figure will immediately give you an idea about the system’s energy generation potential, while the panel count won’t.
In fact, if you’re shopping around for solar, for this reason you’ll almost always see systems marketed in terms of their kilowatt capacity, and not the number of panels.
You’ll need to look at the capacity of the system rather than the number of panels.
The right amount of capacity your home depends on a range of factors. These include:
Without insights into your daily energy usage patterns, it’s hard to know in precise terms how effective a solar system will be at helping you save money on your bills, or what size system would be optimal for your home.
Over 1.5 million Australian homes have made the switch to solar, and most of them have done so without the data to help them make a well-informed decision. As a result, these homes may have systems that are either too large, too small or otherwise not living up to their full potential.
This is where carbonTRACK can help. Our units can be installed before you get solar (or batteries) to help you decide on a system that is best suited to your needs. In fact, our platform can even help you find ways to save energy and money before you go solar and effectively use your solar energy once your system is installed.