So you’re finally ready to install a battery at home. There is much to consider – from cost and capacity to the behavioural changes that can boost efficiency. Here, Guardian readers make it easy by sharing their experiences and offering key pieces of advice for how to get the most out of it.
How to maximise cost savings
Sign up to a wholesale power price retailer so you can charge and export power when it’s financially advantageous. Also, if you have an EV, you can charge for free from solar, or buy super-cheap (under 10c/kWh) power from the grid when it’s windy, sunny and not too hot.
– Mark, Woodend, Victoria
It is unlikely that you will be entirely off the grid with a battery so I recommend hunting for the lowest possible grid electricity prices (what you pay) for when you need to draw off the grid, and don’t worry about the feed-in tariff (what the grid pays you for your surplus) as feed-in tariffs are always stupidly low and make no discernible difference to your bills.
– Peter, Burrawang, NSW
We always keep 25% in backup; since installing the battery to our existing solar system we have saved $11,846.
– Alan, Port Pirie, South Australia
Join a retailer that allows you to access the wholesale market, just like the big batteries. That way you can sell energy from your battery during price spikes for up to $17/kWh (yes, dollars not cents).
– Søren, Canberra, ACT
Consider how much capacity you’ll need
I have a 10kWh battery with micro inverters on the roof. Mostly off-grid now except for winter mornings. Will add more battery capacity later. We need 10kWh plus for a house with electric heating and cooling.
– Alan, Murrumbeena, Victoria
Bigger is better. I have 16kW and it is just enough to heat a well insulated house in winter.
– David, Moe, Victoria
Go big. I have a 22 kW solar system with 54 kW of battery storage and an EV. I have not paid a power bill since 2017. I am now around $10,000 a year better off. I charge the car at home overnight (I’ve never paid to charge it), on average 8 kW a charge. We abolished gas so the house is fully electric. We have no problem running air con and heating. Our house is 100 years old.
– Anonymous, Brisbane, Queensland
Shift your mindset
The one thing to be aware of is that jumping into solar/battery needs a behavioural change. If you’re expecting a set-and-forget solution you will get a very small benefit from the whole thing. You need to check power prices during the day, when is a good time to sell, to charge from the grid when prices are low, to use your power-hungry appliances, etc. The mindset shift is critical, way before installing anything.
– Jorge, Caringbah south, NSW
To ensure you are using only battery-stored power, monitor your use of appliances in the household to avoid drawing too much power at once. This can all be done in your phone app. For example, wait until the cooking of a meal on the stove is over before charging the electric car. This will prevent your system having to draw from the grid. In other words, don’t use too many appliances all at the same time.
– Bruce, Fawkner, Victoria
Resilience in rural areas
Make sure you get a system that will power your house during a blackout, and not find out later that you have to pay more for that function.
– David, east Gippsland, Victoria
We live in a rural area with occasional power cuts that can last more than a week after a flood. Only a few battery systems can accept power from solar panels when there is a power cut. Resilience is very important to us, and such a system does allow one to disconnect from the grid in the future … provided there is also the capability to accept a generator input during an extended period of cloud. Our system is six years old, and doesn’t have that capability. If we are off the grid in cloudy weather for an extended period, we would use gas for cooking and eek out our limited power.
– Bunny, Darkwood, NSW
It’s more about security for me – we have had some big blackouts. But I enjoy playing with the app, working out which appliances use the most power, and shifting them to sunlight hours.
– Anonymous, Coromandel Valley, South Australia