Just over a month after the first shipment of US-made Tesla Powerwalls arrived on Australian shores, the Melbourne home of Victorian Greens leader Greg Barber has become the first in the state to install the 7kWh battery.
The Powerwall – Elon Musk’s take on residential battery storage that effectively put a rocket under the global market – was installed by Natural Solar at Barber’s Brunswick West home, alongside a new 5kW solar system, complete with inverter and in-built energy management software.
And it’s all part of Barber’s plan to side-step Victoria’s “perverse” energy markets.
In an interview with One Step Off The Grid on Wednesday, Barber said the low – and still falling – cost of solar PV meant that it was now a clear winner for Australian households wanting to generate low-cost, clean electricity.
“Panels are so cheap now that we just ordered as much as we could fit onto out roof,” he said – but the “lousy price” for solar electricity exported back to the grid meant having solar didn’t make sense for many households, unless they added storage.
“I’m feeding (electricity) into the grid at 5c/kWh and taking it back out of the grid at 25c/kWh,” Barber told One Step. “I can make it on my roof cheaper than they can deliver it. But unfortunately I can’t throw an electricity cord over the back fence and sell my solar to my neighbour.”
The Barber household – which he says has already done all of the “cheap stuff” to maximise the efficient use of energy – uses between 6-12kWh of electricity a day. The solar system, meanwhile, has so far generated as much as 22kWh in one day.
“We’re frugal users, so without a battery we’d be exporting a huge amount – 10kWh – back to the grid. And we would have been importing 7kWh in the evenings, but – provided we don’t go whoopee – the battery will take care of that.”
Still, he adds, “because of the lousy prices for exported electrons, we’ll be looking at other forms of storage, too; storing energy as cold air, or hot water, or in an EV further on down the line.”
As the system stands, however, Barber says he thinks he’s got the right size to make it NPV (net present value) positive, and is expecting to pay it off in 15 years.
“But that’s looking at the system stand alone,” he adds. “I have other revenue streams. If I reduce my gas consumption or get rid of gas, that contributes to my revenue.
And that will be Barber’s next move – to get off fossil fuel gas, for which the fixed-price cost alone is 70 cents a day. This would mean replacing the instant hot water system, perhaps with a heat pump, solar hot water or electric storage.
But switching to solar plus storage was the obvious first step.
“The rules as they operate in the Victorian energy market are perverse. They drive you – they drive you to install your own energy management system.”
Indeed, the effect of this “drive” to solar and battery storage could soon be writ large in Victoria, and many other states around Australia, when tens of thousands of households come off a 25c/kWh feed-in tariff – a sort of “one-for-one” tariff, says Barber, that plus or minus the benefit solar offers the grid, could be considered a reasonable market return.
On this point, Barber is clear: “changing the solar tariff is not about fairness… and it’s not about incentivising solar, because we don’t need to. It’s about re-introducing some rationality into the electricity market.”