What is a community battery?

A community battery, also sometimes referred to as a “neighbourhood battery”, is a type of energy storage that can increase the accessibility and availability of renewable energy for a surrounding neighbourhood.

These batteries are bigger than a home battery. A typical household battery (often used to store rooftop solar energy) might have a storage capacity of up to about 10 kilowatt-hours (kWh). This might be enough to power your average household for a day. On the other hand, community batteries range from 100 kWh to five megawatt-hours (MWh) in capacity, enough to power a small neighbourhood for a few hours during peak demand, typically in the evening.

Community batteries can be connected ‘in front of the meter’ to the electricity network; that is, they are located outside of your home or property and connected to the local network as a standalone unit. A community battery would typically be located at the street level close to where electricity is being consumed and generated.

Community batteries can be owned by electricity distribution businesses or third parties such as community energy groups, electricity retailers, and private investors.

What does a community battery do?

• Allowing more solar installations: they can enable the network to support more rooftop solar by storing electricity generated by nearby solar systems during the day and discharging it during the evenings when local demand is highest. This can enable people to generate and consume more renewable energy locally and support emissions reductions targets.
• Network support: They can be used to avoid costly network upgrades by proving services that help to manage electricity congestion in the network. Lower costs of maintaining and upgrading the network put downward pressure on electricity costs.
• Community batteries can provide a wide range of social, environment, economic and technical benefits, including:
  Market services: They can participate in spot price arbitrage in the wholesale electricity market (buying electricity when prices are low and selling when they are high), which can help put downward pressure on electricity prices for everyone. They can also provide services that help maintain the security and reliability of the electricity system and reducing the risk of blackouts.

How much energy does a battery store?

Community or neighbourhood scale batteries range in storage capacity from approximately 100 kilowatt-hours (kWh) to five megawatt-hours (MWh), and may service as few as 20 homes up to a small town, depending on the size. YEF’s Fitzroy North community battery has a storage capacity of 309kWh and supplies power to approximately 200 homes during evening peak demand.

How does the battery itself work?

Excess solar energy that is exported to the local network by local properties is absorbed by the battery as it charges from the same local network. This energy is then discharged during times of peak demand – usually in the evening. When little or no locally generated solar is available (for example, on cloudy days), the battery charges from the grid. Typically, this electricity has fewer associated carbon emissions since more renewable energy is generated across the grid during the day (for example, by remote wind or solar farms). The battery itself uses lithium-ion technology, the industry standard form of electricity storage for batteries. This is the same technology used for smartphone batteries and electric vehicles. Read about the battery hardware.

What are the noise levels?

The battery unit does make noise when it is charging and discharging. This occurs during the day when the sun shines and in the evening, especially during peak demand, and not at night. Battery systems will typically include an air conditioning unit which will also contribute to the noise levels of the battery.

For example, the noise from the battery in Fitzroy North (a Pixii PowerShaper) is extremely low. With the installation design co-created by YEF, the local community, and supplier (Pixii), we ensured that noise is not an issue for local residents, even those living closest to the battery. At the time of procurement, we assessed the PowerShaper as one of the best for inner-urban residential environments.

Generally speaking, a community battery (depending on the model and size) could range from about 50-70 decibels at 1 metre from the unit. 50 dB can be equated to the sound of a conversation at home, and 70 dB can be equated to a vacuum cleaner. Note that 50 dB is only 25% as loud as 70 dB because dBA is on a logarithmic scale.

Whether this sound is an issue in practice will depend on:

• Sound treatment within the battery cabinet itself
• Which direction the battery is facing (where is sound projecting and how might it reflect off surfaces)
• The natural acoustic properties of the in situ environment (e.g., is it concrete, grass, vegetation, brick walls, or open space)
• Any environmental sound treatment or insulation as part of the installation
• The distance from the battery to nearby properties (and how sound will degrade over that distance)
• Any competing ambient sounds (like traffic in the distance) that would drown out the sound of the battery

Noise can be managed by installing acoustic panels within or outside of the battery unit. For the Fitzroy North community battery, steps to protect the neighbourhood from noise pollution was a priority for project management and planning, and was managed in consultation with a Community Reference Group made up of local residents.

Are community batteries safe?

Yes, the batteries that YEF has installed are safe. Our selection of suppliers and our testing of their technology follow a rigorous process to ensure that they operate safely and do not pose a fire threat and operate within Australian standards for Electro-Magnetic Fields (EMF).

For the Fitzroy North community battery, YEF worked with a team of engineers from CitiPower (the network distributor), , Pixii (the battery supplier), and Ventia (the installer), to ensure safe installation of the battery.

How can community batteries help facilitate the adoption of electric vehicles?

Community batteries provide storage just as EV charging stations do. The step to adding chargers to an installation is not difficult, but it is not in-scope of the Fitzroy North community battery project.

Community batteries can be seen as helping suburbs to become “EV-ready” and are likely to be a key consideration for future community battery rollouts. YEF is investigating the addition of a co-located EV charger for another community battery slated for installation at Burnley Backyard community centre in Richmond, as part of round 2 of the Victorian Government’s Neighbourhood Battery Initiative.

Will the batteries be derived from the usual Lithium, if so, is there a sustainable source available?

The battery selected for the Fitzroy North community battery, the Pixii PowerShaper, is by far the most sustainable battery model from a lifecycle analysis point of view out of more than a dozen options evaluated through an exhaustive assessment and evaluation process. The battery module manufacturers (Polarium) are the first in the world to announce manufacturing of battery modules made with 100% renewable energy and up to 95% of the physical materials used in the PowerShaper are recyclable. Read more about the battery selection.

Can community batteries be used for embedded networks?

They can, however, it is up to the embedded network operator to initiate the process for embedded network customers. If the community battery was installed outside the embedded network, the embedded network operator could benefit and could pass on the benefit to all of their customers. Communities and developers should engage early in new developments to explore how future communities could benefit from community batteries.