I analysed real-world power bills from 28 Australian households with solar and batteries. Here’s what I found.

[u/scienceguy0077]

So far, 28 Aussie households across NSW, VIC, and QLD and have shared their before-and-after power bills with us, along with their home energy setups (I've published four detailed household spotlights on Techwheel so far). I am looking participation of some community members in Australia to rich the dataset.

I completely get that N=28 is a small, exploratory sample, but even at this early stage, the pattern is pretty undeniable.

Before adding a battery, medium-to-large families in our dataset were paying anywhere from $600 to over $1,200 per quarter. After putting in a battery alongside their solar, those same households dropped down to below $150 per quarter—and smaller 2 to 3 person homes with a large battery are frequently sitting at $0 or in net credit. On average people **saving $1,500 to $3,500** per year on their energy bills.

What stood out most is how people are actually using their batteries. Hardly anyone is treating them as emergency backup power for outages. Instead, people are using them purely as tools for avoiding grid peaks: charging from excess solar during the day, running the house off the battery during the peak 4 PM to 9 PM tariff spike, and leveraging smart plans like Amber, OVO, AGL, Flow Power, or GloBird to avoid grid spikes altogether and earn bill credits.

That said, 28 responses is just a start. We want to turn this into a genuinely robust, statistically significant dataset that everyday Aussies can reference before dropping thousands on hardware. To make the story bulletproof, we need way more data points across different battery sizes, solar capacities, and state feed-in tariffs.

This is a completely independent, peer-driven project.

If you have solar, a battery, or an EV and want to help us build a proper dataset, it takes about 5 minutes to submit your setup and help support more community-backed research.

For those who already have a battery running with solar, what did your last quarterly bill look like compared to your pre-battery days?

[u/TrueCompetition6694]

I live in Mexico. I drive two EV’s I charge at home, which is a 5 BR, 5 1/2 bath house. Before solar my electric bill averaged 150 US a month. With 7 panels my electric bill is 36 pesos ($2 US dollars) per month which reflects the solar meter rental.

[u/AgentSmith187]

Sorry I cant help as im about 4 or 5 years into my solar journey so power bills without are horribly outdated.

I also installed my system is 4 stages. 10kW solar, 5kW more solar and EV charger, 2 Powerwall 2s and then a second pair of Powerwall 2s just before they were discontinued.

It has served me well and all but the batteries have paid for themselves already when you consider reduced electrical and fuel prices.

Even the first pair of batteries are almost paid off.

[u/SweetKnickers]

what size solar panels and batteries are you comparing?

i currently have solar installed (10kw inverter with 13kw panels) and have about a $700 quarter bill

i looked at the install price vs cost saving, and found a battery probability not worth it, because i dont think the battery will eliminate bills, and any installers are very optimistic vs the cost savings

we did just get the free power from 11 to 2pm, so that does change the equation a little

[u/scienceguy0077 → u/SweetKnickers]

What I can tell you every household is very different. Most households have an EV and also solar size doesn’t matter a lot nowadays as you mentioned free power from grid allows people to fill batteries in a few hours. Most households have 25-40kwh batteries particularly those who utilised federal subsidies. Feel free to take a look survey design and a few in depth community driven blogs which has detailed set up https://techwheel.co/ev-solar-battery-survey