A booming market for home solar energy systems is bringing battery storage into the spotlight, but households are being urged to crunch the numbers first.
While solar panel prices have dropped sharply and can now pay for themselves in less than four years, battery systems — which store solar energy for use at night — don’t deliver the same financial benefits yet.
Batteries alone can still take 10-15 years to recover their cost, but solar specialists say there are other reasons tempting buyers, including environmental benefits and protection from blackouts.
Home solar system numbers surged 12 per cent nationally last year to 2.02 million, costing as little as $5000 for a large system. But a typical battery costs about $15,000.
ZEN Energy founder Richard Turner said new players were coming into the battery supply market, which would bring down costs.
“The market I think will get very competitive in the next 12 months and pricing will continue to tumble, like solar has,” he said.
Not all batteries deliver blackout back-up, but households wanting to go green are still signing up, with help from energy incentives in some states.
“Instead of 30-40 per cent of energy from solar you are getting 70-80-90 per cent of your energy from the sun — that’s driving a lot of people,” Mr Turner said.
Home battery customer Jim Young said he had cut power bills by 50-60 per cent since having his battery installed. “The battery makes it possible to spread the efficiency of the system into the evening hours when there’s no sun being generated,” he said.
Solar Quotes founder and CEO Finn Peacock said it was a “big myth that solar isn’t worth it without batteries”.
“People are putting off buying solar because they see batteries as too expensive. They’re not buying something with a four-year payback because they’re waiting for something with a 15-year payback,” he said.
“Batteries make so much sense intuitively, and it feels great, but people have struggled to separate the warm and fuzzies from the financial sense.
“A Tesla Powerwall 2 costs $15,500 installed and it stores about $4 worth of energy,” Mr Peacock said.
But the savings could be less because of foregone feed-in tariffs, he said. “My Powerwall 2 is saving me 90c a day.”