Should You Buy Batteries?
This is a question that I'm being asked more and more.
Before I really dive into it, it is important for you to understand that there are two types of battery storage setups that you can choose for your home:
Off-grid systems mean exactly that - your property is not connected to the electricity grid at all. 100% of your electricity is generated by your solar panels (well, unless you need to fall back onto a diesel generator), and is stored in batteries for use at night. Your property is its own electrically self-sufficient 'island'. No meter. No electric bills.
Note that totally off-grid setups are very expensive - you are looking at $30,000 upwards. This is why most off-grid solar owners live in very rural areas where it can cost tens of thousands of dollars just to connect to the distant grid. In these situations it can be economically viable to invest in a great quality off-grid solar system instead.
But as I explain in another post, for most suburban Australians, off-grid systems make absolutely no economic sense. So from here on in, I'll talk about batteries in the context of hybrid solar systems.
Hybrid systems are setups where your property is connected to the electricity grid. However, hybrid systems will prioritise the use of stored electricity in your batteries over electricity from the grid - because it's a lot cheaper to use electricity you generated yourself instead of paying 31c/kWh to buy it from the grid!
Even hybrid systems are pretty expensive. I go into more detail about the expected payback periods of hybrid systems here, but simply put, adding a decent amount of battery storage to your system (about 7kWh worth of good quality lithium ion batteries) will set you back about $10,000.
Who's the ideal candidate for a hybrid solar system?
In a nutshell? People who want batteries for non-economic reasons.
Let me explain. Battery storage prices are not yet at the level where it makes economic sense for the average Australian to add batteries to their home. You are looking at a 20 odd year payback on batteries with an expected lifespan of 10 years. Ouch.
But not everyone cares about payback when buying batteries. Some people are prepared to spend the money to get their grid imports as low as possible, stick it to the electricity companies and bugger the payback. If that is you - good on ya. By buying batteries now as an early adopter you are supporting the battery storage industry in these early days.
For the rest of us, we can expect batteries to reduce in cost quickly over the next few years. Battery prices are dropping drastically as more and more companies enter the marketplace and the underlying technology becomes cheaper to manufacture. I expect in 5 years time (2021) that batteries will be as prevalent as solar panels.
In the mean time you can prepare for batteries by buying a 'battery ready' solar system.