Should you buy Battery Storage with your Solar System?

Interest in battery storage for homes increasing rapidly as families seek to take control of their energy.

2018 was Australias best year for battery storage and it looks as though 2019 will be better! Batteries are in high demand thanks to the promise of energy self-sufficiency and back-up power in the event of blackouts, but are they safe? Solar battery storage, regardless of wether its lithium ion, lead acid, flow or aqueous hybrid ion, is perfectly safe if it is installed by an accredited electrician.

Safety checklist –

  1. Know what type of battery storage system (i.e. battery chemistry, power and energy size) you are having installed. Different battery types have different requirements.
  2. Use a Clean Energy Council Accredited Designer/Installer with the ‘battery storage endorsement’ to design and install your system.
  3. Understand what you will be using your battery for, and the amount of energy available for your use (this is usually less than the manufacturer’s rated total amount of energy labelled on the batteries).
  4. Monitor your system regularly (at least once a month) and ensure that you: a. have a system in place – for example, an appropriate battery monitoring system, a log book, and a visual and audible alarm b. know what to check for when doing a visual check or taking meter readings.
  5. Batteries do not perform well with sudden changes in ambient temperature, so they must be appropriately housed with adequate airflow. On extremely hot or cold days, you may need to do additional monitoring; ensure you have a system in place to remind you to do this.
  6.  Ensure your batteries are not accessible to children, are vermin proofed and are separate to the living areas of the house. Do not store items on top of or lean items against your batteries or enclosures, because they could be a potential electrical fire risk. Consider installing signs to remind you of this.
  7.  Ensure your batteries have the correct safety and warning signs for the battery type, and that you know how to follow their instructions (e.g. emergency shutdown procedure and emergency action plan).
  8.  Keep manufacturer and installer and warranty information to refer to as needed, and use only accredited installers and professionals to alter the system. Revisit your whole system periodically and replace or upgrade components as required. Your accredited installer should be your first point of contact for maintenance. Keep the installer’s contact details.

Mercedes home energy storage

Battery storage, a good investment?

About 80% of batteries installed are lithium ion which generally have a 10 year warranty. If your serious about installing battery storage you must at least break even on your investment over that period.

Example of a ‘worth it’ investment.

For the purpose of this exercise we won’t take into consideration the credit you will receive from the energy you export back to the grid that would normally offset your nightly usage. As the energy stored in your battery will only be used at night we will calculate the cost of energy use at night to see how many years it would take to ‘break even’ on your investment.

  • Average cost of solar battery storage including installation – $7000
  • Average use at night – 15kWh or $3.30 (depending on your state) $3.30 x 365 days = $1204
  • Average payback period – $7000 divided by $1204 = 5.8 years.

With the cost of batteries decreasing, and safety not being an issue we will begin to see a mass uptake of the technology and see Australians take control of their energy.