What Size Solar Panel System Do I Need?
Teenage climate activist Greta Thunberg reached New York last week after sailing the Atlantic for fifteen days on a zero-emission boat powered by solar panels and underwater turbines. Perhaps Greta’s zest for sustainable living has got you thinking – ‘What can we do to reduce our carbon footprint?’ As a homeowner, one way to achieve that goal is to consume clean energy by installing solar PV panels on your roof.
Installing solar PV (Photovoltaic) panels on your rooftop makes good sense both from the perspective of reducing your carbon footprint and lowering your monthly household expenditure on electricity.
Is this the year to Go Solar?
To answer your concerns, we just published a blog on the economics of installing solar PV panels. As a general rule, if you have a quarterly power bill of at least $400, installing a solar system for your home will give you enough savings to recover the cost of installing solar PV panels in a span of around three to five years.
As an Australian homeowner, installing solar PV panels is a win-win situation for you. Here is how you benefit from installing solar PV panels on your rooftop –
- Reduce your power bill: Firstly, the generated solar energy will power everything that is connected to mains power, excluding anything connected to an off-peak supply such as some electric hot water systems and pool pumps. Using solar power directly reduces your power bill as you are no longer buying power from the grid. The more power you use during the day, the more solar power can help.
- Feed-in-tariff (FiT): If you don’t use the solar power generated, it is automatically fed out to the grid. As a payment, you can receive a feed-in tariff credit on your power bill from the energy retailer. The FiT rate varies from around 8 cents up to 16 cents per kWh depending on your location and the agreement you have with your retailer. We have many customers that have installed the largest possible system and then maximised their system’s impact by negotiating a high FiT with their retailer to the point where they don’t pay a power bill. More on that here: How to eliminate your power bill with solar power.
- Solar installation rebate:As an added bonus, when you install solar PV panels, you also earn a certain number of STC’s or small-scale technology certificates. Depending on the prevailing STC price, the value of the STC’s is deducted from your overall installation cost. Even with the solar rebate being phased out, installing a solar power system at home in 2019 will still save you around thirty percent of the gross installation cost.
Sizing up a solar system
If you are keen on going solar, first measure the current daily power usage for your household to determine how much power you need to generate from the solar PV panels (the average Australian household consumes 20-30kWh of electricity each day). Next, assess what purpose do you want the solar system to serve. Do you only want to generate enough power to run your home during the daytime? Or would you also like to have the capacity to store excess solar power in a battery to keep your home running on solar at night?
Detailed information: How to size up a solar system
Maximize the Solar Potential of Your Roof
The size of your solar panel array is a crucial determinant in the power generation capacity of a home solar system. The most popular residential solar PV panel sizes available in 2019 are – 5 kW, 6kW, 6.6kW, 8kW and 10kW, with the average having doubled in the last few years to now be over 6kW.
Generally, the larger the size of the panel array, the more power your solar system will generate. That, in turn, delivers lower dependence on the power grid, greater capacity to earn a feed-in tariff, and a faster return on your investment. But before you conclude that ‘bigger is indeed better,’ you must evaluate which system size is ideal for your home.
For instance, a 3kW solar system may be adequate to power your home during the day with little or no excess exported to the grid. However, for most customers, a larger system generates excess power that can either be fed out to the grid or stored in a battery for use at night time. Given that the price per kW generally gets smaller the larger the system, most customers are now sizing up their solar system to generate their average daily usage to give them flexibility to add batteries later on.
We know from experience that there is no one-size-fits-all solution for PV solar panels. It really depends what you are trying to achieve, with the main two options being to reduce your power bill by as much as possible or to get the optimal return on your money.
We’d be happy to offer a customized solar power solution for your family’s home if you share a few details with us. The Solaray Team has access to detailed digital aerial photos to assess if your home’s roof is suitable for solar power. We can accurately measure how many solar PV panels will fit on your roof, although a site visit may also be required to confirm the measurements.