Batteries: An energy storage solution

Battery technology is used to store solar and wind energy in the form of electricity so that the electricity can be used day, night, or on overcast days when the energy sources are not in use. The lack of such steady supply of electricity is why there is a need for large energy storage systems (ESS). Energy storage systems require load levelling or grid storage batteries in order to provide a seamless flow of electricity.

Lithium Ion (Li-ion) Batteries

Lithium ion (Li-ion) batteries are preferred for their Load Levelling capabilities due to the small footprint, long life, and low maintenance. Even though Lithium ion batteries are more expensive than lead batteries, Li-ion batteries do not suffer from sulfation like lead acid batteries when not fully charged periodically. This is a problem on a mine site where demand often exceeds supply. The benefits of Li-ion batteries are that they are light weight and easily transportable to remote locations. The drawback to Li-ion batteries is the high cost. The batteries best suited for ESS are lithium ion or redox flow batteries.

Figure 2, Lithium ion battery cross section

Vanadium Redox Flow Batteries

Vanadium Redox Flow batteries (VRB) are fuel cells designed to store electricity. The fuel cell contains an electrolyte (metallic salts) that gets pumped through a core that consists of a cathode and an anode that are separated by a membrane. Electricity is generated by an ionic exchange that occurs between the cathode and anode.

Industrial types of flow batteries consist of an electrolyte that is made of sulphuric acid with vanadium salts. Vanadium is often used as it keeps corrosion under control. Large scale flow batteries are capable of between 100KWh to 60MWh and can be used for frequency regulation. Vanadium batteries are excellent at storing energy for large power systems.

Figure 3, Vanadium Redox Flow Battery

Battery Management Systems (BMS)

Wind turbines have an energy output between 1-10MW averaging out around 5MW. Most wind farms contain several wind turbines that produce between 30-300MW and require battery management systems. Battery management systems (BMS) keep the batteries at 50% charge to absorb energy during windy days whilst delivering on high load demands. Modern BMS can switch from charge to discharge in less than a second in order to stabilize the voltage on transmission lines.

With the network undergoing an exciting transformation, we’re evolving to give customers more choice around how they generate, use and store energy. One way we’re doing this is with community batteries. As part of our community battery program, we’re rolling out various batteries across Perth metro and regional WA to deliver immediate benefits to the local community and the grid. There are currently 13 community batteries across the network. Batteries are transforming the grid and play a big part in connecting WA to a brighter energy future.

There are currently three types of large-scale energy storage systems being used across our network:

  • Large network batteries that form part of a microgrid, like the one in Perenjori
  • Community batteries located in suburbs store unused solar power to smooth power flows
  • PowerBank batteries are a form of community battery that allow customers to store their excess solar energy and use it later when energy demand is high

How does a community battery work?

Community batteries benefit the entire community, whether you have solar panels or not. This is because they are placed in areas where the network needs upgrading or adjusting to maintain power reliability and quality. For example, for an older part of the network, there might be too much pressure on a transformer to accept two-way flow of power.

Community batteries solve this problem. They soak up any excess solar power and smooth the flow, improving power reliability and quality to customers. It’s a win-win for customers and the grid. One of the benefits is that it provides opportunities for residents to trial innovative storage solutions, such as the PowerBank, a virtual solar storage option. Participating households feed their excess solar energy into the battery, then draw the energy back to power their homes during peak times.

What makes a community battery so appealing?

Some of the benefits of community batteries include:

  • They can help balance electricity supply and smooth out the flow of power on the grid
  • In the case of a microgrid battery like in Perenjori, they can be used as a backup power supply, which will assist when there is a fault on the main electricity network, power disruptions due to severe weather, or as part of an independent microgrid
  • They can reduce the high cost of upgrading existing power infrastructure in areas that have high energy demand during peak demand hours
  • PowerBank batteries can potentially help reduce your electricity bill and generate revenue at the same time
  • Support a higher uptake of renewable energy allowing more homes to install solar panels

Driving forward WA’s battery industry

Storing solar power in a battery is nothing new. But the application of it at a community level is world leading. Discover the WA council and the Busselton-based company that have helped us drive battery storage forward in WA.

How a WA community became 221 times more sustainable:

  • Home to more than 88,000 people, the City of Mandurah is no stranger to renewable energy, which is why the city gladly welcomed its first community batteries on the grid.

Energising a battery industry from the ground up:

  • Battery technology is gaining momentum in WA. We’ve been key players in the battery industry for a while now, but there are some players that have played an important.

The PowerBank Trials

In partnership with Synergy, PowerBank batteries were trialled in Meadow Springs in 2018. The second trial saw two more PowerBanks installed in Falcon and Ellenbrook. These trials provided participants with an alternative energy storage option to expensive in-home batteries. PowerBanks use Tesla battery technology made of lithium ion. Entrepreneurs like Elon Musk, the founder of Tesla, are leading the way in new lithium ion battery technology and the future of electric vehicles. In 2021, a third PowerBank trial was announced. It was the largest trial to date and saw nine of the 116KW community batteries transition into PowerBanks.

Around 2.2 million Australian households have solar. So, for many the next step is to consider a battery. There has been increasingly more interest in batteries and electric vehicles, except that none of it is really new. What is new is the viability of this tech in WA. Batteries are a win-win for the community and the grid, and this technology is creating new models for how we use the grid.