New research supported by German automaker Audi has highlighted how intelligent and grid-optimised electric vehicle charging can relieve stress on the electricity grid, effectively dismissing the claims of EV critics who doomsay street-wide blackouts if multiple EVs charge at the same time.
Audi worked with German IT service provider GISA and other software and hardware partners to simulate an overload scenario on a local power grid – based around multiple electric vehicles charging at the same time and with high power on a street supplied by a local network transformer.
The small-scale test highlighted how intelligent and grid-optimised charging, through the intelligent management of charging procedures, can prevent grid overload.
Specifically, utilising a device known as a smart meter gateway which provides targeted communication between the charging electric car and the grid operator, charging can be scheduled to take place during periods of lesser grid demand.
This technology allows EV charging to be controlled to reduce stress on the grid, and can control charging capacity, charging time, and charging duration.
Audi’s involvement in the test specifically focused on the necessary technology already installed in the Audi e-Tron or Audi e-Tron Sportback, which allows charging capacity to be reduced by up to 11kW as standard and by as much as 22kW upon request.
The specific case scenarios which were proven in the test include the possibility that an Audi e-Tron owner who can charge their car at work may be able to accept certain limitations when charging from home – easing demand on the local grid – and, in return, obtain power from their provider at a discounted price.
Beyond the mechanics of charging electric vehicles, smart and intelligent charging such as this can also lead to further benefits, such as electric vehicles acting as virtual battery storage for renewable generated electricity.
Specifically, as has already been proven possible, electric vehicles with smart charging can charge to full when electricity generated by renewable energy sources like wind and solar is feeding into the grid, effectively storing that electricity, and dispatch it back into the grid when needed – all of which can be regulated by intelligent controls.
Further, the technical requirements for all of this are often already in place. Electric vehicles are, of course, increasing in popularity and number, but smart meter gateways are often already in place.
For example, Germany has already mandated that all households with annual power consumption exceeding 6,000kWh must have such gateways. Such gateways are often part of national digitalisation of the electricity grid, and in time will become commonplace.
All that is needed, then, is for EV manufacturers to follow in the footsteps of company’s like Audi and ensure that all future models include intelligent controls.
Australian electricity retailer Origin Energy announced in mid-2020 plans to roll out smart EV chargers to up to 150 customers to test remote monitoring, control, and optimisation. The $2.9 million trial, partly funded by the Australian Renewable Energy Association (ARENA), was launched to evaluate the needs of EV owners and understand EV driver behaviour.
“EV adoption is expected to increase significantly in the coming years with the price of new EV models continuing to fall and performance and range improving all the time,” Origin’s general manager for future energy and technology, Tony Lucas, said.
“We hope this trial will help us understand how we can maximise the benefits to customers by offering products that reduce their EV charging costs, as well as how we can manage EV charging in a way that helps with grid and network stability.”
Similarly, the South Australian State Government has already initiated plans to explore ways that electric vehicles can act as mobile batteries.
Announced in September, the SA Government announced that it would spend an initial $4.9 million on its EV Action Plan to facilitate private investment in charging infrastructure, boost grid reliability and lower transport and energy costs.
The focus of the plan is to investigate how EVs can act as mobile batteries and as a “solar sponge” – soaking up excess solar during the day for use in the evening.
“What’s clear is that as electric vehicles become more affordable, smart charging can reduce drivers’ fuel bills and reduce the cost of power for all South Australians,” energy minister Dan van Holst Pellekaan said, speaking in September of 2020.
“By charging at low demand and at sunny or windy times, electric vehicles will allow us drive down wholesale electricity prices, reducing the cost of a unit of power for all South Australians,” van Holst Pellekaan said.
“A key action in the plan will be to support electric vehicles being used as mobile batteries which can be filled at low electricity demand times of the day and discharged at peak times.
“Discharge can occur the car into the home or grid in the evening when electricity is expensive and then recharged overnight when electricity is cheap.
“With smart charging infrastructure, time of use tariffs and electric vehicles as “surplus solar sponges”, we can reward customers who charge their vehicle when excess energy is available and prices are low.”