a home battery energy storage located in a garage with a sunny background with lawn car, family house and big city.

Is battery storage right for me?

Battery storage allows you to store electricity generated by solar panels during the day for use later. It’s an exciting technology and there are many things to consider before you invest in a system for your home.

Benefits of battery storage

Installing a Battery Energy Storage System (BESS) can provide a number of benefits when used in conjunction with an existing or new solar panel system.

A battery storage system can:

  • store excess solar energy so it can be used at night (depending on your feed-in tariff)
  • help further reduce your reliance on fossil fuel-based electricity from the grid
  • offset the increased cost of power used during peak times, such as during the evening
  • save money by storing energy from the grid overnight when prices are low to use during peak times when prices are high (depending on the agreement you have with your retailer)
  • provide electricity to your home during power outages (depending on your system).

Choosing the right BESS for you

The type and capacity of your battery storage system will vary depending on whether you're looking to:

We understand that sometimes the household or business budget can be tight and you're looking for ways to reduce everyday essential costs like electricity. We also know that you can't live without it. So you may decide to get a battery storage system to reduce your power bills.

Here's what you'll need to consider:

  • Which appliances you wish to run from your battery and for how long - including the maximum usage, or peak demand, at any one time. This is so your battery installer can work out what 'usable energy' and inverter size is required to meet your needs
  • What tariff you're on – for example a time of use tariff offers lower electricity costs at off-peak times
  • Your electricity usage
  • How much electricity the battery storage system uses – as a storage device it actually consumes some electricity
  • If you already have a solar PV system, you'll need to look at what battery systems work best with it and this may affect price
  • The pay-back period of a battery storage system, including installation and maintenance costs.

Today's lifestyle relies on having electricity around the clock; both at home and at work. We want to be able to switch on our appliances when we wish. Power outages are inconvenient, so having a back-up electricity supply could be an option to keep you out of the dark.

If you're considering a battery storage system for back-up power, you'll need to think about:

  • The electrical appliances you'll need during an outage, and the battery capacity required to run them. Even if just essential appliances are needed (ie. refrigerator, freezer, one light per room and the TV) a small battery storage system may not be able to power them all for very long in back-up mode
  • The length of time you would like to have these appliances available - 6, 12, 24 or 48 hours? Once you know the number of hours and total electricity these appliances can use, including if they were all on at once (peak demand), your battery installer can work out what usable energy and inverter size you need
  • What circuits your battery storage system can connect to. You may need a split electricity switchboard featuring 'essential' and 'non-essential' circuits. This ensures the best outcome for your system in back-up mode
  • Not all battery storage systems offer back-up power.

  • If you are thinking of purchasing a battery storage system to power your entire premises, have a look at our go off-grid information. Off-grid battery storage systems must meet Australian Standard AS4509 Stand-alone power systems.

Renewable energy generation technologies, such as solar PV systems, are a great way to help you achieve a more sustainable lifestyle, but solar energy can only be used during the day. In the morning and evening electricity has to be bought from the electricity grid.

With a battery storage system you can work towards your sustainability goals by storing excess renewable energy for later use.

When considering combining renewable energy generation and battery storage, you'll need to think about:

  • How much electricity your renewable energy source can generate and do you need to increase its capacity
  • How much electricity your premises needs over a typical 24 hour period
  • Your typical maximum daily electricity usage or your peak demand.

Your system installer will help you understand BESS functionality and choose a system appropriate for your requirements. The decision will be based on your energy use and tariff, the size of your solar panel system, and what you are wanting from the system.

Here are some key factors to think about and discuss with your installer.

  • Calculate the cost of the battery system itself and the likely payback rates, as well as the potential energy savings, to get a complete picture of the total installed cost of the system.
  • Learn more about the technology. Do you know how much excess energy you generate from your solar panels each day? Are you comfortable using an app or portal to manage your BESS?
  • Do you have appropriate space to install the battery? For example, manufacturer requirements might dictate the battery’s distance from the meter box, the size of the PV inverter or access to an internet connection.
  • Do you have an appropriate location to install the battery? Talk to your installer about the requirements of Australian Standard AS5139.
  • Can the battery store and supply enough energy for your needs? This will depend on the nature of your household appliances, and your household energy usage patterns. Shift workers may have different needs from a family who all get home from work or school at the same time.
  • How do you expect to use your battery system? Is your aim to save money in the long term? To contribute to sustainability? Or have a back-up plan for blackouts?
  • Is the supplier a reputable company who can deliver on any potential warranty claims? Be sure they offer adequate after sales support and advice when you need it.

To get the most out of your solar and battery system, you may choose to reduce the amount of electricity you use in the evenings or overnight so you only use solar or solar-charged battery power. For example, you could run your washing machine or dishwasher during the day when your solar panels are generating power.

How much power you need from your BESS

When thinking about what you need from your battery energy storage system, there are two key concepts to understand:

  1. power – how fast energy can be supplied (kilowatts, or kW)
  2. energy – how much energy is stored by the system (kilowatt-hours, or kWh).

Some people like to think of this as the difference between your car’s speedometer and odometer. The speedo tells you your current speed (how much power you are using right now) [kW], while the odometer tells you how far you’ve gone (how much energy you’ve used in total) [kWh].

Your power requirements across the day will change depending what appliances you are using, when they’re switched on, and how long you run them for. Getting smarter about how your household uses power can lead to a reduction in your overall energy needs, which impacts your BESS requirements. Visit our Save money & electricity for tips and tricks.

Most battery systems currently on the market have a power rating around 5-12 kWh. Multiple systems can be used to scale this up if necessary. A ‘typical’ house may use around 18 kWh of energy per day, although this can vary significantly.

Remember that as long as you stay connected to the grid, your battery storage system doesn't need to provide for all of your needs. The BESS and the grid can work in tandem to ensure you have all the power you need, when you need it.

Typical maximum power requirements of some high-power appliances are:
AppliancePower requirements
Air-conditioner2 - 12 kW
Water heater3.6 kW
Clothes dryer2.4 kW
Electric kettle2.4 kW
Hair dryer1 - 2 kW
Dishwater1.5 kW
Washing machine1.5 kW
Microwave oven1.5 kW
Plasma TV0.8 kW
LED TV0.2 kW
Lighting:
Incandescent
Dichroic
LED

100W
50W
6W

As a general rule of thumb, any appliance that cools or heats will need more power than other appliances.

FAQs

There are different types of battery energy storage systems (BESS) on the market, and each has distinct benefits and characteristics.

To choose the right BESS for your needs, it’s useful to understand the features of this type of battery technology, as well as the different models of battery available.

For more information read our FAQs.