Millions of Australian homeowners are making their home more sustainable by switching to solar power, but are solar panels right for you? To help you answer this question, we’ve selected key questions that by answering can help you make an informed decision about your solar panel and sustainable home upgrades.
1. How much energy are you using?
If you’re thinking about installing solar panels, a great place to start is with your current electricity bill. This will help you to determine your daily energy requirements.
For every 1kW of solar panels, you can generate 4kWh of electricity per day on average. So if your household is currently using 20kWh per day on the grid, as a rule of thumb, a 5kW solar system should keep things running nicely.
You can find the average annual electricity usage for households in your area here.
2. When are you using your energy?
Once you know how much energy you are using, the next step is to understand when you are using it. Start by reflecting on your daily routine and cross-checking it against your electricity bill, focusing on these two pieces of information:
Average daily use: On your electricity bill you will see a bar graph representing your electricity usage in kilowatt hours (kWh). If you are on a time of use tariff, you can see your average energy usage during peak, shoulder and off-peak periods.
The usage charge: This will be shown as cents per kilowatt hour (c/kWh).
If you have a time of use tariff, you may observe that your 'peak' usage is high - this may include the use of your TV, air conditioner, dishwasher etc. In such cases, you may consider installing west-facing solar panels to maximise your solar energy production during busy afternoon periods. You could also consider installing a solar battery to ensure coverage into the evenings and to avoid expensive peak tariffs from your energy provider.
3. Is your property suitable for solar panels?
Let’s have a look at the factors that need to be considered:
Roof Type: Every roof material is suitable for solar, except for slate. (Because slate is so fragile, most installers aren’t willing to work on it).
Tiled roof: No tiles are broken, however they are removed for brackets to be inserted and then re-installed.
Metal roofs: Existing screws will be removed in favour of strong, stainless steel screws, a single penetration to run the D.C cable to the inverter is required which is full waterproofed.
Roof Space: A 5kW system (a commonly installed residential system size in Australia) contains 15-20 panels and requires approximately 25-35 m2 of roof area.
Roof Slope: A moderate roof angle is best for solar electricity production. If your roof is either flat or very steep, your solar system may require tilt frames (and thus additional expense) for optimum sun exposure.
Roof Condition: Most roofs in good condition will support the typical solar panel’s 10-20 kg per square metre. However, your roof does have to be in good condition.
Roof Shade: Consider how much shade is cast onto your roof by trees and surrounding structures. Shade can drastically reduce your solar panel system’s efficiency, so it’s a good idea to remove or minimise it as much as possible. Don’t forget to consider shading at different times of the day, as well as when the sun is lower in winter. Your installer may also recommend the use of microinverters or optimisers to maximise the efficiency of your solar system where shading is an issue.
Roof orientation and sunlight hours: With Australia being south of the equator, it is optimal to install solar panels on a tilted, north-facing roof. In homes without a north-facing roof, solar installers can use a strategy called 'follow the sun', whereby panels are placed on the eastern and western sides of your roof to ensure a portion of your solar panels are always facing the sun and providing generation earlier in the morning and later into the evening. South-facing panels are generally not recommended as their efficiency will be significantly reduced, especially in winter.
- A north-facing roof will receive the most sunlight throughout the day.
- An east-facing roof: will receive almost as much sun as north-facing panels, your panels will receive the most sunlight during the morning.
- A west-facing roof: will receive the most sunlight in the afternoon.
Finally, it’s important not to compromise the effectiveness of your solar panels by ‘hiding’ them in areas of your home with reduced sunshine. The design of solar panels is ever-improving, so if aesthetics are your number one priority, then for a price, some companies have started offering solar roof tiles.
Did you know that Australia is one of the best places on earth to install solar panels? Our sunny climate means we have access to some of the best solar energy resource in the world.
Adding solar panels to your home is great step in creating a sustainable home for you and your household. By generating your own energy you rely less on the grid, further optimisations are possible to utilise the energy generated by your solar panels which will optimise your energy savings even further.