Four years ago, Tesla installed its first ever Powerwall battery pack in an Australian household, and now the residing Pfitzner family has revealed just how much of an impact the energy-saving measure has made.

When combined with a solar panel system, Powerwall allows users to store any excess energy generated by the panels in order to use it at times when the sun alone can’t provide the necessary power.

While this effectively allows a home to operate self-sufficiently, there is a still a need to rely on the main power grid when the battery depletes due to extended periods of inclement weather or similar.

Over the course of four years, this resulted in the Pfitzner family saving a total of about $5,700 (AU$8,463) on their electricity bills, paying an average of just 30 cents (AU$0.46) per day.

As for the environmental impact – the ability to store reserve energy in a battery pack has the potential to reduce household carbon emissions by up to 6 tonnes per year, which would be a significant figure if the technology was installed in masses of homes.

The Pfitzner’s house is described as having “four bedrooms, internal laundry, air-conditioning, state of the art appliances, a pool, and outdoor entertaining area”, so it’s likely more resource-intensive than the average household.

It’s worth noting that the family spent AU$16,000 (about $10,800) installing the battery, solar system, and any related hardware to the home, so it hasn’t quite paid itself off yet.

While the initial estimates for the return on investment were around the 20-year mark, it’s now set for just seven years, which is much more promising for the development of household battery technology in the future.

[via Natural Solar]