Earlier this month, Tesla unveiled plans to install solar arrays and Powerwall 2 batteries in 50,000 homes across South Australia. Now, a new study reveals just how dramatically Tesla’s new solar project could cut electricity costs for those in the region.

In November 2016, RenewEconomy determined that people living in the South Australian capital of Adelaide could save just a small amount of money if they sourced their electricity from 5 kW of rooftop solar panels and a Telsa Powerwall instead of from the power grid. Thanks to a drop in panel pricing and the launch of the Powerwall 2 in the years since, the difference is now far more pronounced.

According to RenewEconomy’s latest report, the average price of a 5 kW solar array is now $5,500 AUD, falling by almost $2,000 AUD since 2016. The price of storage via a Powerwall 2 is about half that of a Powerwall 1.

Today, the average price of electricity for a customer using 4,800 kWh per year is 42.4 cents per kWh if they take advantage of all available discounts. Through Tesla’s new solar project with the South Australian government, customers will pay just 27 cents per kWh, although the authorities will retain ownership of the panels and the Powerwall 2 batteries.

The end result is that participants in Tesla’s new solar project can expect to pay around $1,300 AUD per year for their electricity, assuming they’re consuming 4,800 kWh annually with the panels installed on a north-facing roof. By comparison, going grid-only will cost them upwards of $2,035 AUD.

The biggest drawback to a project like this one, which is expected to cost around $800 million AUD, is the up-front cost, but RenewEconomy’s report demonstrates the potential long-term benefits.

If other regions in the nation and beyond see that solar can work for the South Australian government and its citizen, they could be empowered to take a chance on the technology themselves, which would be good for the environment and the average citizen.