Getting a rebate on your power bill for driving an electric car is the end game for wooing more customers into zero-emission vehicles.
A taxpayer-funded trial program starting up in the ACT by the end of this year aims to set up a program whereby electric vehicle owners will provide a backup to the grid in times of high power demand.
The program basically aims to identify every electric car that joins the national fleet as a potential power source. By hooking those cars to "smart" chargers, the charge they retain in their batteries becomes a backup supply.
When the grid draws on a car's battery storage, that's when the value of that power goes back into the consumer's pocket.
And if a consumer can generate the power to run the car from a source external to the grid, such as through a home solar panel array, that's when the ownership value equation starts to make good fiscal sense.
The ACT trial program is a slow-burn game-shifter for the electric vehicle industry which has struggled to interest consumers due to the relatively high purchase and leasing costs of the cars, limited driving range and slow recharge times.
The latest electric-only Nissan Leaf, with its 40kW/h battery and extended 315-kilometre range, for instance, costs a minimum of $50,000.
While the range and recharge issues are still ongoing because of slow gains in battery technology, using your car to push charge back into the grid when it sits idle is seen as an important step in attracting new customers to zero-emission vehicles.
The ACT's program is a first for Australia, but there are similar programs operating on a smaller local and regional scale in Japan and parts of Europe. Australia's renewable energy agency is giving ActewAGL $2.4 million to fund the project and its research
Nissan's second-generation electric Leaf, introduced mid-last year, is the only vehicle on the market which has a bi-directional capability and is fully warranted by the factory for that purpose.
The ACT government currently has 15 bi-directional Leafs and will lease 51 more as it steadily replaces combustion engine cars on its fleet.
The technology which allows the batteries to be used as an energy source is known as vehicle-to-grid technology, or VTG. It will allow for what's known as frequency control ancillary services (FCAS) to be provided to the national electricity market.
Power comes into the national grid from a number of energy sources - solar farms, wind farms and coal-burning power stations - but this will be the first time cars will join them.
The Australian National University is a key technical partner in the project. Research leader Dr Bjorn Sturmberg, from the ANU Battery Storage and Grid Integration Program, believes the project has the potential to enable a more resilient energy system with higher levels of renewable energy, like rooftop solar.
"One EV battery typically contains as much energy as an average household uses over two to four days," he said.
His team will create a grid simulator inside the ANU's labs and then push the car's charger to respond to the frequency disturbances that occur when the grid is on the brink of a blackout.
The smart charger known as a Wallbox, made in Spain, is critical to the project. Wallboxes cost around $2000 each. In a blackout, when the grid needs support, these chargers will draw down on the car's battery at the grid's request, leaving just enough charge to allow the car to be driven a reduced distance.