Surviving blackouts: As trees fell on power lines, I turned to the EV sitting in my driveway

Last Saturday night, according to the headline, some 30,000 Tasmanian homes were without power. Moments later  a tree outside my window toppled into power lines, bringing them crashing down in a rain of sparks to block the only road into town.

As my freezer slowly and silently defrosted on a Sunday filled with the buzz of chainsaws and generators, I thought about how the 40kWh battery in the Nissan Leaf sitting in the driveway is more than capable of running my household’s electrical needs, and that of the neighbours as well.

Australia has around 15.3 million passenger vehicles registered and on the roads (plus nearly 4 million light commercial vehicles), and as we switch to Electric Vehicles (EV) to decarbonise our transport, there is an amazing opportunity for these vehicles to assist the wider energy grid as it weans off fossil fuels.

Vehicle to Everything (V2X) technologies allow us to use EV batteries just as we would use a home battery such as a Tesla Powerwall, a community battery, or a grid scale battery.

This could allow EV owners to use their home solar energy at night, make money from the energy markets, and may even reduce the need for new transmission lines or large scale storage projects such as pumped hydro.

V2X is the catch all term for several functions; Vehicle to Home (V2H), Vehicle to Grid (V2G), or Vehicle to Load (V2L). V2L is already available in many EVs on the Australian market, and means running an appliance, such as a computer or a kettle, from a power point built into the car.

During 2023 Christmas storms in Queensland, several EV owners used V2L to run essential home appliances during 2023 storms in Queensland, and to power the dialysis machine needed for a sick child. But V2L can only be used for stand alone loads, not to feed a grid connected system.

V2H allows for a vehicle to power a home or building; self consumption of energy created from home solar or on boarded during off peak hours.

The average Australian household uses 18.7kWh (kilowatt hours) a day, and the average EV battery holds 70kWh, so a house run entirely from an EV battery overnight will use less than 20% of a battery capacity. For comparison, a Tesla powerwall is 13.5kWh.

V2G takes this a step further and enables owners to sends energy back to the power grid during peak hours, when power prices are high.

Home solar systems receive a low feed in tariff, as they are selling energy when solar is abundant. Home batteries can participate in a Virtual Power Plant (VPP), sending energy to the grid when prices are high (but retaining enough energy for home functions).

V2G will use the same VPP technology to interact with the grid, but when most vehicles are electric, the virtual power plant can be your local suburb- creating power through rooftop solar during the day, drawing a little from each vehicle at night.

This could even protect local energy networks in severe weather events, allowing homes and businesses resilience to continue functioning through long network outages.

Speculation on the future role of V2G is very exciting, but more needs to be done to bring the technology to fruition.

Trials are being conducted in Australia and around the world, and developments involve the coordination of energy retailers, vehicle manufacturers, charging hardware suppliers and VPP operators to create a functional system that ensures the best deal for vehicle owners and the best benefit for our energy systems.

To bring this technology forward, the Tasmanian and Australian governments, and power infrastructure companies such as Tasnetworks, must fund research and development on these technologies, and ensure they are utilised for the good of the community.

Perhaps next time a tree takes out my power lines, I’ll have my electric car ready to keep the freezer running, look after my neighbours, and make a cup of tea for the council workers clearing the road.

Andrea Persico is an EV consultant with Amped Consulting, and a Carbon Zero Clean Energy Champion.