Solar is installed on the shared rooftop and the electricity is used to power common areas.

This is often the simplest solution, since only one electricity meter and electricity account is involved. It can also a good option where roof space is limited, or if there are extensive common areas with high energy usage, such as lifts, a gym, pool or large air-conditioned common areas.

It is easy to split the benefit equally, through a reduction in strata fees for common areas. As this option is limited to powering the common areas, there is no reduction to any owner or tenant’s electricity bill.

Another option is to install individual systems connected to the electricity meters of individual units. This can work well for low-rise buildings of three storeys or less, as roof space is allocated for each individual apartment’s solar system.

This can be a simple way for one or more residents to get solar even if not everyone is involved.

Once the systems are installed, this option works just like solar on a freestanding home, with no need for additional metering or monitoring equipment, and no interaction between your solar system and your neighbours’ systems.

New technologies are making it possible to more easily and equitably share the benefits of solar, even in high density buildings.

For example, Richmond-based company Allume Energy's SolShare technology enables residents to share the benefits of a single large solar system and see reductions in their energy bills. This technology splits solar usage equally among participating apartments and businesses in the same building. At the time of writing, Allume Energy is the only provider of this technology.

This option allows residents to opt-in, so it can work well even if not all owners want solar. Because this kind of technology maximises the amount of solar used within the building, it can also be a good option where roof space is limited, relative to the number of apartments.

With new technologies developing, it is expected that more providers will launch similar offers or other solutions for apartments. If this kind of solution seems right for your building, carry out research to find the latest available options.

With an embedded network, all apartments are connected to the grid through a single meter, and purchase electricity from the same electricity retailer.

These are more common in larger, high-density apartments. Better electricity rates can be negotiated through the combined buying power of the whole building. Being part of an embedded network requires all apartments to be involved, and usually means it is difficult or expensive to change energy retailers for individuals who want to opt out.

If you are already part of an embedded network, you may be able to install solar which is owned by the Embedded Network Operator and on-sold to apartments in your building at a lower cost. This can be a good option for buildings with an existing embedded network where all apartment owners want to participate.

Another option is a green embedded network, where the Embedded Network Operator supplies 100% GreenPower to the building at a bulk purchasing rate. New Victorian embedded network regulations mean that more Embedded Network Operators are offering GreenPower plans. Contact your Embedded Network Operator to ask about their GreenPower plans.

Visit the Australian Energy Regulator for more information about embedded networks.

In this option, your owners’ corporation agrees to collectively purchase energy from a renewable source, either from an on-site or off-site solar installation. A Power purchase agreement (PPA) maximises your collective buying power to secure a lower cost of renewable energy.

This option does not require any changes to metering or wiring, but does mean participating apartments will receive two bills – one from your regular electricity provider and one for your portion of energy from the PPA.

If you decide that none of these solar solutions are right for your building, you can still choose renewable energy through your retailer.

When you choose 100% GreenPower from your electricity company, every megawatt hour (MWh) of electricity that you use is matched by a MWh of renewable energy supplied to the Victorian electricity network.

Find out more about purchasing certified GreenPower.

There are a number of new ways to buy renewable energy that are starting to become available. These include virtual power plants, micro-grids, solar gardens and other ‘offsite solar’ solutions, software platforms offering energy trading and sharing, and investing in community energy projects.

Many of these solutions are now in trial or pilot phases, or limited in availability, but may become more widely available as technologies advance and regulations change.