What size solar system do I need and how to evaluate it?

So, you have decided to harvest sunlight to get green solar energy for your home. The first thing you will ask yourself is, what size solar system do I need? This question is crucial, but the answer creates further questions and we are here to answer them. Investing in a renewable energy source like solar for your home requires some prior planning. The maximum electricity output of a solar system is its size or capacity. Let’s evaluate some key aspects first before answering your question.
What size solar system do I need

Assess home electricity loads for solar system capacity

Knowing your electricity load during the day and its variation in a year is crucial before sizing your solar system.  Kilowatt-hours (kWh) is a primary energy unit to calculate home electric loads.  To give you a better understanding of kWh, let’s use the example of  of an electric heater of 1000 watts (1kW) which is operating for one hour.  It means the heater uses 1 kWh of energy whilst a 100-watt bulb lighting for 10 hours will use the same 1 kWh.  You don’t need to calculate the energy usage of every electrical device to assess solar system size to meet the requirements.  You can find monthly usage on the utility bill, and it will help you estimate your daily usage.

How many solar panels do I need?

If you have no space issues, buying more panels is a wise choice as they come cheaper. More panels will help you produce more power resulting in more offset on electric bills. As a result, the higher feed-in tariff will also save you more money and give you an excellent ROI value.

As an example, for the Ultimate Energy Australia 6.6 kW solar system size, you will need twenty 370W solar modules. Each module requires 1.7 m², and for t panels, you will need 31 m² of free space.

Is 6.6 kW solar enough?

A 1-kW solar system produces around 4 kWh of energy on a sunny day whilst the daily usage of an average Australian house is around 20 kWh. This means the 6.6kW capacity solar system that Ultimate Energy Australia offers is more than enough for an average home.

The solar system size impacts its upfront cost significantly. But in the long run, solar systems with more power output offer more savings and higher ROI. As you go for more power output in solar, you pay for per kilowatt cost reduces significantly.

With the declining prices of solar PVs and lucrative government incentives, you can save up to one-third of your upfront cost. To learn more about solar energy’s rebates and financial benefits, read our article on Solar Rebate NSW 2021.

To wrap things up, What size solar system do I need? You should go for a 5-kW plus solar system capacity for your home. A 6.6 kW solar system bundled with a 5-kW inverter is an excellent choice and a future proof option.

Scroll to Top