Choosing a battery to suit your needs
Choosing a battery to suit your needs
Batteries store electricity in a chemical form, inside a closed-energy system. They can be re-charged and re-used as a power source in small appliances, machinery and remote locations. Advances in battery technology may one day help to solve our energy crisis. The articles on this page explore advances in battery power technologies
Whether you already have a solar system and you'd like to use more of its energy, or you want your own back-up supply, battery energy storage may be worth considering.
There are different types of battery storage systems, however most households use lithium-ion technology.
How battery storage systems work
Battery storage used together with solar power can help reduce your electricity bills by storing the solar energy you generate during the day so that you can use it when you need it. Watch the video below to see how batteries work with solar power.
Is storage right for you?
If you're thinking of installing batteries to save money on electricity, it's worth weighing up the whole-of-system cost against how much you're likely to save over time. This will help you work out if installing a battery is right for you.
It's important to be aware of the following:
- Batteries have a limited lifetime: they will only last a certain number of years and can only be recharged a certain number of times.
- To preserve the life of your battery, you may not be able to use all of its charge. For e.g. some batteries should only be discharged to 50% (this is called 'depth of discharge').
- As electricity moves in and out of your battery, some energy is lost along the way. How much energy is lost when your battery is used (also known as its round trip efficiency) will depend on the type of battery.
- Some household battery systems are designed to be scalable, which means the amount of electricity stored can be increased by joining batteries together (like adding panels to a solar system). This can help meet changing energy needs over time.
- A special room or enclosure may need to be built to house the batteries.
- Consider the amount of batteries you need, and whether they'll be able to supply the immediate power (start-up current) required for your appliances.
Battery manufacturers publish detailed information on expected life, depth of discharge and round trip efficiency for their products.
This video explains more about choosing the right sized battery for your needs and how battery storage can work with a solar system to save money on electricity costs.
Choosing a battery to suit your needs
When choosing a battery for your home, one of the first things to think about is how you want to use it. For example, you may want a battery to:
- Use more of your solar energy instead of exporting power to the grid (saving more money).
- Provide back-up power during a blackout. This may require special wiring by an electrical contractor, and if you plan to use your current system you may need a different inverter.
- Save on grid electricity costs by buying and storing energy at off peak times (when the price is cheaper) and using the battery during peak periods (when electricity is more expensive).
- Power your entire home (i.e. go off grid). If used together with a renewable energy source, batteries can provide power in remote areas where it is expensive to connect to the electricity grid or the electricity grid is not available.
Understanding how much electricity you use (and when you use it), the tariffs you are charged to buy electricity from the grid, and the size of your solar system will help determine how a battery might benefit you. Using this information, you and your installer can work out what size and type of battery is best to meet your needs.
Checklist for getting started
- Find out what type and size of battery will best suit your household needs.
- Get several quotes before you buy.
- Choose a good quality battery and a reputable installer: you're more likely to get a good outcome.
- Check the licence details of any electrical contractor involved in the installation. They should also be accredited by the CEC to ensure they are specifically trained in relation to these systems.
- Read through and understand the battery manufacturer's technical and safety information, including installation location/requirements.
- If you already have solar on your roof, ask if you need your current inverter replaced or a second inverter installed to retrofit the battery to your system.
- Find out what the costs are for a maintenance plan. You should also know the expected life of the battery and disposal costs. You may void the warranty if your battery system is not operated as specified or properly maintained.
- Contact your home and contents insurance provider to make sure you have adequate cover.
- Connecting your battery to the electricity grid may require approval. Check with your installer and/or electricity distributor before agreeing to buy a battery system.
Finding an installer
Batteries can be dangerous if not designed, installed and maintained safely and properly, and according to the manufacturer's requirements. It's important that you deal only with properly licensed and accredited installers. Here are some things to think about when looking for an installer:
- Check the installer is a registered/licensed electrical contractor in Queensland
- What battery design and installation accreditation does your installer hold? This is different from their qualifications and accreditation to install solar.
- How much experience does your electrical contractor have designing and installing battery storage systems?
- Does your installer work for a reputable business that will be around long term in case you have warranty issues?
A good place to start is the Clean Energy Council's register of accredited solar installers. The Council is currently developing guidelines and an accreditation regime for grid connected battery storage system design and installation.
Questions to ask your installer
Ask your supplier/installer the following questions:
- What is the length and what are the terms of the battery warranty?
- What maintenance regime is required under the terms of the warranty?
- If problems arise with the battery, who is responsible for conducting repairs or replacement under the warranty?
- What happens to the warranty if the supplier goes out of business?
- Do they provide an optional service agreement to maintain/service the battery system regularly?
- What performance guarantees do they offer for the battery system?
- What workmanship and product guarantees do they offer?
- How long has the product manufacturer or importer been making batteries? Do they have an Australian office?
- What safety hazards relate to the battery technology and how does their installation address the safety hazards?
- Does the battery comply with standards for safety and performance?
- Has there been independent accredited testing and certification of the batteries and other components?
- Do they check their products to ensure the quality is ok and the batteries are the same as those tested by the manufacturer?
- Can the manufacturer track down batteries by batch number if they find a quality assurance fault, to rectify the issue?
- Does the installer register the batteries installed with the battery supplier/manufacturer?
- Do they or the battery supplier have Australian recall insurance or can they prove that they can afford to conduct a recall?
- Do they install components (other than the battery) from reputable suppliers who have Australian certification, or adequate testing, for their components and have recall insurance (or can afford to conduct a recall if needed)?
- Where do they locate the batteries so as to not inconvenience the home owner, and prevent inadvertent access or damage?
Find out more
Battery safety and maintenance
Batteries can be dangerous if they are not used and looked after properly. Your battery energy storage system should have an instruction manual and a maintenance schedule provided by the manufacturer.
Talk to your installer about setting up a regular maintenance plan (and how much this might cost) so you can get the most from your battery storage system.
Note: all photovoltaic systems require routine maintenance. If you haven't had your current system maintained since it was installed, consider engaging a contractor to inspect your system to keep it running efficiently and safely.
- The Clean Energy Council has further information about safety, and sets out what you need to know about safely installing and maintaining a battery system.
If things go wrong
For minor incidents such as a fault alarm or a system malfunction, contact your installer for assistance. If a serious incident occurs (like a fire), call 000 immediately. If an incident does occur, wherever possible you should also advise emergency services about the type, size and location of any battery energy storage system at your property.