Grid-optimised charging, aligned with users’ needs, can help to increase the acceptance of electric mobility further– that’s the goal of the dynamic and connected charging developed by Audi.
If all electric vehicles in circulation were charging at the same time, the power grid would suffer a blackout – that is one gloomy vision of the future that electric mobility skeptics love to paint. But in response to this pessimistic vision Audi is developing intelligent charging integrated with the grid.
This solution means electricity loads in power grids can be optimised, ensuring electric mobility is not restricted. Smart charging is already supported in the Audi e-tron range and by the Audi e-tron charging system connect.
To simulate and evaluate overload scenarios, Audi collaborated with GISA GmbH, a specialist in providing electric mobility services. The simulations used an overload scenario in the local power grid: multiple electric cars charging simultaneously and with high power on a street supplied by a single transformer, thus risking a blackout. Connected grid-optimised charging is designed to counteract this scenario through the intelligent management of charging procedures, thereby preventing a grid overload.
Electric cars and grid operators communicate in real time, allowing the charging procedure to be managed remotely and adapted to current requirements. In practice this means delayed charging, dynamically adjusting energy demand and taking into account both the actual load in the power grid and the user’s desired time of departure.
Audi’s solution means that electric cars use downtime to fully charge with dynamic charging capacity adjustment while also relieving the power grid – all without restricting the user’s mobility needs. It’s a win-win situation for everyone.
Smart Meter Gateway
What makes the intelligent integration of recharging procedures and the power grid possible is a device known as a smart meter gateway (SMGW), which establishes a highly secure connection between the house and the grid operator as well as providing detailed information on energy consumption. All necessary information and control signals are transmitted either to the home energy management system (HEMS) or to the Audi e-tron charging system connect.
This means users’ energy demand is constantly under control and charging speed can be adjusted according to remaining capacity, without the risk of overloading the grid. To give a practical example, for the Audi e-tron1 and e-tron Sportback2, which are equipped with the technology, charging power (capable of reaching up to 22 kW) can be reduced as required.
The networking technology will allow the charging to be personalised for every single car, in terms of charging duration, the time the process starts and finishes, and in terms of charging capacity, thus opening new prospects. For example, customers who are able to charge their Audi e-tron at work could accept certain limitations while charging at home. In return, they would obtain the power from their provider at a discounted price.
For this reason, intelligent charging is an important element in boosting electric mobility and expanding the charging infrastructure. Provided that its potential is exploited to the full, it may also be possible to use electric cars as flexible storage devices for renewable energy – a resource with very inconsistent availability, especially in the case of solar and wind power.
To exchange information between houses and grid operators and enable grid-optimised charging technical standards are necessary. Audi has been involved in developing these through the EEBUS initiative.
It aims to promote a common communication protocol so that photovoltaic systems, charging infrastructure, electric cars and domestic air-conditioning systems are able to communicate with each other without interference.
The carbon neutral future
Audi is one of the first automobile manufacturers to sign up to the Paris Agreement on climate change. For this reason, it is pursuing a number of initiatives to lower its CO2 emissions and boost sustainability in the automotive world, including the goal of launching around 20 fully electric models by 2025 and making all its activities carbon neutral by 2050.
1) e-tron 55 quattro – 22.3/26.0 kWh/100 km – 371/437 km – 0 to 100 km/h in 5.7 seconds – 200 km/h top speed
2) e-tron Sportback 55 quattro – 21.9/25.7 kWh/100 km – 375/446 km – 0 to 100 km/h in 5.7 seconds – 200 km/h top speed
Figures relative to consumption recorded in WLTP combined cycle and expressed as a range subject to differences determined by equipment.
Source: AUDI AG