Owners of solar systems connected to Western Australia’s Horizon Power network are being incentivised to rethink how their home PV plants are exporting electricity to the grid at times it is least needed.
Under the state government’s new Distributed Energy Buyback Scheme (DEBS), electricity exported between 3pm and 9pm will earn 10c/kWh, more than three times the 3c/kWh it will pay at all other times.
The announcement is the government’s attempt to manage grid stability in a state where high penetration of rooftop solar is seeing its coal and gas fleet, which generates at least two-thirds of the state’s power, manage an increasingly steep ramping up to evening peak load.
The buyback includes exports from batteries and electric vehicles, which should boost investment in storage. It also favours those whose panels are oriented westwards.
“This strategy aims to better integrate new technologies, enabling a greener grid for the benefit of all Western Australians and avoids the risk of needing to limit new solar installations,” the government said in a fact sheet for owners of PV systems.
The new tariffs will apply from November 6, to allow time for installers to recalibrate inverters to match up with the opportunity to maximise revenue.
Systems with a generating capacity of 5kW or lower are eligible, as is a 6.6kW system with a 5kVa inverter. Home batteries or EVs that can discharge into the grid (and not many can, yet) can be any size.
“The new rates encourage households to use more of their own solar energy generation in the middle of the day when it is plentiful, and to install west-facing panels that will generate electricity later in the day … producing more renewable energy when it is in high demand,” the government said. “These new incentives will enable the grid to become greener by integrating more renewable energy systems whilst keeping our electricity system reliable and secure.”