How much can a family living in a four-bedroom house save by using the Tesla Powerwall and good ol' solar power? The figure has come in at $2110.46 a year for the Pfitzner family. Here are the details.
Tesla introduced its Powerwall battery unit that can store solar energy to Australia last year.
Natural Solar helped the Pfitzner family installed the 7kW Tesla Powerwall battery back in January 2016 along with an array of 5kWp solar panels. The company also installed a SolarEdge inverter and implemented a cloud-based power monitoring software.
The family, based in Sydney, has since managed to reduced its total power costs by 92.2%, amounting to an annual saving of $2110.46.
The family's average power cost was $572.29 per quarter in 2015. It has now dropped down to $44.68 per quarter. In October, the Pfitzner's power bill was in credit $50.25.
But the Tesla Powerwall and supporting hardware are not cheap. The Powerwall and solar panels will set you back around $14,000 (that's excluding GST) from Natural Solar. That's just the starting price. Nick Pfitzner told CHOICE that he paid $15,990 for his system. it's a huge investment, even when you can pay it off gradually on a payment plan. You can get two 300cc motorcycles with that much of money (sorry, I couldn't help myself).
However, the Powerwall does kind of pay for itself - it will just take some time.
The Pfitzners sell their unused electricity back to the grid. Nick Pfitzner told CHOICE:
The system will power whatever the house needs first as a priority, then it will fill the battery as a second priority and then anything over it'll export," he tells CHOICE.
The aim is to try and export about three times of what I import because my electricity cost is about three times [as much].
The rate for selling electricity back to the grid is usually around 8c per kWh, but since the family spent an additional $800 to installed a Reposit monitoring system, they are able to bump that price up to around $1 per kWh, depending on demand.
According to Natural Solar managing director Chris Williams, based on the Pfitzner's first 12 months of power bills, the return on investment and payback period would be six years. The Pfitzners said it may take eight years.
"With Tesla Powerwall 2 installations expected to occur in a matter of weeks, the anticipated ROI of solar and battery combined will only improve as the market mature," Williams said.
Are you considering getting a Tesla Powerwall for your home? Let us know in the comments.
Back in May, 2015, we crunched the payback figures for the Powerwall, based on an assumed Australian cost and example electricity prices. Now there are local installed costs available, we have broken out the calculator and gone over the figures. The question is, can the Powerwall give a decent payback time?