Audi tests grid black-out prevention with e-trons

German carmaker Audi has set up a small-scale test in Germany to mimic one of the ‘horror scenarios’ skeptics of the electric car are projecting for the future: a black-out of the grid. The latter could become likely when several owners of powerful EVs want to charge locally at the same time. The solution, says Audi, is “preventing black-outs with intelligence.”

But the technology promises benefits for the future EV owner, too, as the customer can negotiate from the grid operator a lower electricity price in return for voluntary limiting its charging capacity during peak hours. And that’s only one of several other possibilities.

Audi worked with IT service provider GISA GmbH and other partners to simulate an overload scenario with several e-trons in a particular street in Chemnitz (Germany), supplied by a local grid transformer. This requires intelligence at the car’s side and the grid’s side to avoid a black-out scenario.

Smart meter gateway

The grid’s connection is guarded by a smart meter gateway (SMGW) at the home’s side. In Germany, such an SMGW is mandatory for households exceeding  6 000 kWh electricity consumption per year.

Europe proposed to have 80% of all households equipped with a digital electricity meter by 2020, but the roll-out timing is a matter of the member states themselves. In Belgium, this goal of 80% will rather be achieved by 2035, with Flanders and Brussels already actively installing them since 2019 and Wallonia somewhat trailing behind.

Grid-optimized charging

The so-called ‘grid-optimized charging’ is achieved by having the electric car communicate with the grid operator through the SMGW. In practice, says Audi, this will mean delayed charging, taking into account the desired departure time and the power grid’s actual load.

It’s nice for the car owner to have the car charging at full capacity at downtime when electricity prices are low or when solar panels provide maximum input. The benefit is the cars adjusting their charging when the load is high, preventing an overload and possible black-outs for the grid operator. A win-win at the end of the day, Audi says.

Secure data connection

The Audi e-tron and the e-tron Sportback can be charged up to 11 kW as standard, and up to 22 kW as an option, with the Connect system reducing charging when requested. The cars have the intelligence already built-in, as will all future Audi EVs.

But to enable the car to talk with the grid, it’s mandatory that they at least speak the same language via ‘a highly secure data connection’ through a certified IT backend. In this case, Audi partnered with Robotron Datenbank-Software GmbH to provide the software for the backend, and KEO GmbH to develop the communication interface. EMH metering GmbH &Co KG provided the hardware.

Attractive prospects for an EV owner

This small-scale test focused particularly on ‘grid-optimized charging’ to avoid black-outs, rather than on the benefits it can have for the EV owner. “In the medium term, the new networking technology will allow the charging capacity, charging time, and charging duration to be controlled for each car,” Audi says in the press release.

“Besides, some attractive prospects may arise: A customer who can charge his Audi e-tron at work could accept certain limitations while charging at home, for example. In return, he would obtain the power from his provider at a discounted price.”

This vehicle-to-home (V2H) or vehicle-to-grid (V2G) bi-directional charging is seen as one of the main advantages of the future EV.  There is the possibility to use your EV as a backup battery for your home appliances. Or to sell back electricity to the grid operator when a shortage is threatening. The latter being a backup solution for the grid itself.

You could draw electricity from the grid in off-peak hours when prices are low, or store your own electricity produced by solar panels or a windmill and sell it when prices are high.

One million EVs equal nuclear powerplants

With one million electric vehicles in Belgium by 2030, for instance, a fleet of EVs could deliver a backup solution equalling nearly today’s 5 MW nuclear capacity of the Thihange and the Doel powerplants combined. It’s a line of reasoning that Belgium’s major electricity supplier, Engie Electrabel, keeps in mind.

In July of last year, Audi announced it is teaming up with Hager Group, a German world leader in electrical installations, in a research project to make its e-tron capable of fully bi-directional charging.

In the summer of 2019, Mitsubishi Motors started in Japan, putting the Dendo Drive House on the market. This solution combines solar panels, a home battery, and a bi-directional charger with a Mitsubishi plug-in hybrid or electric vehicle.