Install solar for your apartment
You can place solar panels on your building and wire them directly to your apartment, providing power and reducing your personal energy bill.
Installing a solar system to power your own apartment presents an excellent opportunity to cut your energy bills and protect yourself from rising electricity prices.
What will it cost?
A small 2kW system might cost around $4,5001. Appropriately sized systems can pay back your up-front investment within five to nine years2.
Is my apartment suited to solar?
The installation of solar systems is recommended for apartments in buildings:
- with four storeys or less, and
- where each apartment has its own electricity meter and receives individual bills
Buildings higher than four storys are okay as long as installers have somewhere to safely work from and a way to get their equipment up.
If you don’t receive individual electricity bills for your apartment you might live in a building that has an ‘embedded network’. In these cases sub-meters are used to measure the exact amount of energy used by individual apartments and common property. It’s a good idea to talk to your strata manager or executive committee if this is the case.
Note that installations to multi-story buildings can sometimes incur additional installation costs due to the difficulty and infrastructure sometimes required to get the solar equipment in place.
Steps to installing your solar system
Check your apartment building for places where solar panels could be mounted: the roof, external walls, facades, or even above windows.
Solar panels need as much sun a possible so ensure surrounding buildings or trees will not overshadow them. Consider where the shadows of buildings and trees fall at different times of the year, and watch out for smaller objects such as TV antennas. If even one panel is shaded, the performance of other panels can be severely impacted.
Consider future shadows due to building developments – are high rise developments or building extensions planned for neighbouring properties? Call your local council and chat with neighbours to gauge future plans.
Your panels will perform best when they face the sun. North-facing panels generate the most energy but North-West facing panels are also appropriate for apartments because residential energy use typically increases during the late afternoon.
How much space?
The average solar panel is about 1.6 metres long and 0.8 metres wide.
A 1kW solar panel system will require around 8-10 square metres of space, and a 1.5kW solar panel system requires around 12 square metres of space.
One of the first questions you need to answer before starting your solar project is: who owns the roof, wall or façade where the system will be installed?
The roof and external walls in apartment buildings are often collectively owned by the owners corporation. In this case you will need to work closely with your owners corporation to get your solar project approved.
You may want to consider the following questions to help you communicate with your owners corporation:
- Is it fair for one owner to claim a section of the shared space?
- What if other owners want to use that space in the future?
- Is there enough space for all owners to have a certain sized solar system in the future?
A planning permit is not usually required to install solar unless your building has heritage significance and is covered by a Heritage Overlay in your local council’s planning scheme. Check with your local council to make sure the local planning requirements allow for solar.
Understand energy use
You may need to consult an expert to determine the right size solar system for your apartment. Alternatively, an installer may also offer advice. Before you consult an expert you will need to understand how much energy you use at home.
If you look at your energy bills you will see that your electricity consumption is measured in kilowatt hours (kWh). There are three ways to understand how many kWh of electricity you use each day:
- Many energy distributors and retailers have online portals that allow you to view your electricity use in real-time and will show you how many kWh you use each day and if this varies from season to season
- Look at your electricity bills for the past year - most bills will have a graph that shows your average daily kWhs
- Quote the National Meter Identifier (NMI) number when you contact your electricity retailer or distributor to ask for the detailed data recorded by your electricity meter
If you live in Victoria then check this list to see if your retailer or distributor has an electricity portal or you could just phone your retailer.
You will get the best value from your solar system if you size the system to match your daytime energy use. The amount of energy you use will vary throughout the day as appliances are switched on and off and also across seasons.
Choose the right solar system
For quickest payback, you should match the size of your solar system to your daytime energy use. Your installer will also be able to provide advice about the best size system for your apartment based on your billing data.
The more solar panels your system has the more renewable energy it will generate . However, the payback period for a large system may be longer because it may take longer to pay for itself in the form of energy bill reductions.
Another important consideration is the amount of space available for solar panels to be installed on your building. In the future, other apartment owners in your building might also like to install solar panels and it could work in your favour to only use your fair share of the available space.
If your building has limited space you might consider using high-efficiency panels, which cost more than standard panels but generate more electricity per square metre.
Solar panels must be mounted securely to resist high winds. Most roofs and external walls are strong enough, but the installer will check this. If you or your installer have any doubts, it is best to obtain advice from a structural engineer. Some roofs, walls and facades require specialised equipment to install or maintain solar systems, for example, a high-rise apartment block or steeply pitched roof can mean a more expensive installation.
Where panels are easily accessible to residents, they should be fenced off for safety purposes.
Some roofs and walls have a waterproofing membrane. Penetrating the membrane when installing solar panel should be avoided wherever possible. There are less invasive solar panel mounting systems designed specifically for flat roofs.
Where membrane penetration cannot be avoided, they should be kept to a minimum. Consideration should also be given as to how a membrane would be repaired or replaced in future. It is best to discuss waterproofing with your solar installer and determine who is responsible if leaks occur.
In strata buildings, shared walls between apartments are often rated for fire-proofing. You should check with the installer about whether solar cabling would compromise this. It may be possible to lay the cabling externally. Any penetrations holes that might impact on fire safety separation between apartments, or between apartments and common areas, should be discussed with the building’s fire services company.
Tips for choosing a trusted supplier
Ensure your solar supplier is accredited by the Clean Energy Council
Ask lots of questions, the Clean Energy Council has some tips and a list of questions to help when choosing a supplier
Choose a supplier with experience in designing and installing similar systems for apartment buildings, and seek references from those buildings
Obtain at least three detailed quotes and ensure your quotes are for the same size system
Seek independent advice on panel quality from you local sustainability organisation (eg Alternative Technology Association)
Ask for detailed contracts and agreements
Insist on seeing the warranty details (products and service) before signing
Ensure local suppliers are available to fulfil any warranty claims that may arise in the future
Visit the Smart Blocks ‘Contractors and quotes’ page for more information and templates you can use for requesting a quote.
2 Souce: Alternative Energy Association
1 National average after STC rebates. Source: Solar Choice