Solar + flow batteries take Brisbane home off grid, no back-up required

A Brisbane doctor has tapped home grown zinc-bromine flow battery technology to take his dream home on Tambourine Mountain off-grid and 100 per cent renewable powered – no back-up generator included.

James Emmett has installed three of Brisbane-based Redflow’s 10kWh ZCell batteries at his home in the hills – one during construction to supply power for the builders, and another two when construction was completed.

Teamed with a Victron inverter-charger, a Fronius inverter, and 13kW of ground-mounted solar panels, Emmett says he is cruising through off-grid living, with plenty of energy to power his three-bedroom home, his Hyundai Kona electric car, and his electric lawnmower.

James said he chose Redflow’s zinc-bromine flow batteries due to their durability and ability to withstand extremes of temperature.

“My reasons for choosing Redflow batteries were their heat tolerance and capacity to be at any state of charge without damage to the battery,” he said.

“I have no backup generators here, so the system has to do black starts occasionally. As an example, one night I left the car charger on by mistake and we got down to 1 per cent of stored energy in the morning before it started charging again when the sun rose.

“I like that I don’t have to worry about a full discharge damaging the battery whereas with a lithium or lead-acid battery, that could damage it.”

All up, the solar and flow battery system is enough to power the lighting, air conditioners, ovens, washing machines and home entertainment systems – and to charge the car and mower.

Emmet said that while cloudy days could cause some mild anxiety, he was determined to get by without a diesel-powered back-up generator.

“One thing I really value is the ‘smart battery’ capabilities provided by the Redflow BMS (Battery Management System),” he said.

“I can monitor the batteries from an iPad in our kitchen to see their state of charge and, if I am away from here, I can use the Victron portal on my mobile phone.

The doctor also values the sustainability of Reflow’s batteries which, as well as retaining their full storage capacity throughout their operating life, can be easily recycled or reused.

He’s also been very happy with Redflow’s remote system monitoring service.

“They have helped to set up and configure the system. On one occasion, I didn’t even realise I had a problem, but they called me to say they had spotted an issue and were sorting it out.

“Redflow’s remote monitoring really pays dividends. Having an Internet connection and monitoring the batteries helps with their maintenance.”

Sophie Vorrath

Sophie is editor of One Step Off The Grid and deputy editor of its sister site, Renew Economy. Sophie has been writing about clean energy for more than a decade.