Audi has developed an innovative generation of smart power meters that could help avoid a growing electric car fleet crashing local power distribution grids at peak times – a popular criticism by EV opponents.
The new grid-optimised charging system establishes ‘intelligent’ communication between electric vehicles, households and the power suppliers, through a network of Smart Meter Gateways (SMGs) that relay critical information regarding energy requirements and demand.
With this real-time data, the system identifies high load periods on the distribution network and staggers the delivery of power on an individual basis, eliminating a spike caused by multiple EVs being plugged in at the same time.
It’s the same problem sometimes encountered on hot days when many households switch on air-conditioning simultaneously – normally about the time residents are returning home from work.
Audi’s solution has one key difference. While the cooling effect of air-conditioning is required immediately, Audi’s system recognises that electric vehicles do not necessarily need to commence charging as soon as they are connected to the power supply.
The system effectively creates an adaptable roster during which the connected vehicles all receive power, but not at the same time.
One potential problem with that approach concerns vehicles with large battery capacities and longer charging times, requiring continuous charging overnight to receive their maximum range. But Audi has a solution to this.
Customers who are able to charge their EVs at work, for example, would be offered electricity rate discounts to partially or fully top up their battery during the day and eliminate the need for a full eight-hour connection each evening.
That option might not work for everyone but the German carmaker says it will only be necessary in a handful of cases. Overload simulations and testing conducted by Audi has demonstrated the system has the potential to keep everyone happy.
“The electric car uses downtime to fully charge with dynamic charging capacity adjustment, while also relieving the power grid without restricting the customers' mobility needs,” Audi said.
Crucial to the success of the test and future commissioned systems is a universal communication language used by all components in the chain.
Using special modules, a home energy management system (HEMS), smart gateway, Audi Charging System Connect and the grid all use the same code to form a ‘highly secure’ data stream.
In collaboration with the other system stakeholders and partners, Audi is also developing its electric models to seamlessly plug in, including the e-tron which is already being manufactured with the relevant software to connect.
Audi’s Grid-Optimised Charging is the latest in a number of ventures that seek solutions to a looming grid overload problem – a challenge that will only get harder to overcome as the number of EVs on roads and driveways increases.
Last year, the Australian Renewable Energy Agency (ARENA) contributed $838,000 to a $2.9m project to install and commission 150 smart chargers locally. While that’s a relatively small number, the pilot will help ARENA better understand the demands of Australian EV drivers and enable a more targeted expansion of the network when the demand increases.
A key part of the Australian smart charger project is to also gauge the public’s willingness to hand over data regarding energy use to a third party, a potential stumbling block for any ‘intelligent’ energy management solution.