Green light for the "Bidirectional Charging Management (BCM)" research project.

Munich. The newly launched Bidirectional Charging
Management – BCM research project brings together companies and
institutions from the automotive, energy and scientific sectors. They
have teamed up to develop technological solutions for making electric
mobility even easier and cheaper for users, with even lower emissions.
By adopting a holistic approach, the project’s interdisciplinary
partners are aiming to interlink vehicles, charging infrastructure and
power grids for the first time in a way that facilitates the widest
possible use of renewable energy – and at the same time increase power
supply reliability. The research project will run for three years
under the aegis of the German Aerospace Centre and with funding from
the German Federal Ministry for Economic Affairs and Energy. Testing
of the first 50 BMW i3 cars equipped with bidirectional charging
technology (i.e. that are capable of backfeeding) is expected to start
under real-world everyday conditions in early 2021.

Not only will electric vehicles with bidirectional charging
capability be able to draw electrical power for their high-voltage
battery when plugged into a compatible charging station or wallbox,
they will also have the ability to reverse the process and feed energy
back into the power grid. This will effectively turn the electric
vehicles’ batteries into mobile energy storage devices that can also
supply electricity when required. Integrating as many electric
vehicles as possible into the power grid in this way calls for myriad
innovations in terms of vehicle technology, charging hardware,
charging management, communication interfaces with energy sector
stakeholders and legal parameters. Bringing about these advances is
the task of the research project, in which the BMW Group is acting as
consortium leader. It is joined by KOSTAL Industrie Elektrik GmbH
(development of charging hardware), transmission network operator
TenneT  and distribution network operator Bayernwerk Netz GmbH (both
energy system services), the Research Institute for Energy (FfE) and
Research Association for Energy (both energy system analysis), the
Karlsruhe Institute of Technology (KIT; research into electricity
market and grid repercussions) and the University of Passau (user research).

Expanding electric mobility enhances power supply reliability.

Although the fleet of electric vehicles on our roads keeps growing,
this only results in a slight increase in the amount of electric power
required. However, there is a growing need to control energy flows
intelligently in order to make optimum use of electricity from
renewable sources. The BMW Group has already succeeded in implementing
methods of intelligent charging control in pilot projects. For several
years, intelligent charging management to meet the needs of both the
customer and the power grid has been undergoing practical trials in
everyday conditions in California with a fleet of 300+ electric
vehicles. This has paved the way for the BMW Group to team up with
power grid operator TenneT to develop an innovative solution in
Germany that allows the charging strategy for electric vehicles to
factor in the customer’s mobility schedule, the availability of green
electricity and the current load on the power grid. It means
plugged-in vehicles can suspend and later resume charging when
prompted by signals from the grid operator.

The bidirectional charging technology (for backfeeding power) now
being explored could lead to even greater benefits. Indeed, it allows
parked electric vehicles hooked up to a charging station or wallbox to
be used as flexible energy storage devices. During periods of
particularly high demand for electricity, these vehicles are able to
feed additional power into the grid, while their high-voltage
batteries are mainly charged at times when overall demand is lower. In
this way, electricity from renewable sources can be tapped and stored
as it becomes available. And the stored energy can, in turn, be
deployed exactly when needed, whether for electric driving or boosting
power grid capacity. Electric mobility can therefore help to stabilise
power grids and limit the need to expand them, keeping electricity
prices stable.

Bidirectional charging assists the energy revolution.

As well as improving power supply reliability, intelligently
controlled integration of electric vehicles into the power grid can
also further increase the proportion of renewable energy in Germany’s
overall electricity consumption. By utilising the storage capacities
made available in the high-voltage batteries of electrified vehicles,
supply and demand for green power can be reconciled more effectively.
Using these electric vehicles as a means of buffer storage allows the
potential of wind farms and solar plants for carbon-neutral energy
generation to be exploited to an even greater degree.

For example, a surplus of solar power can be stored in the vehicles’
high-voltage batteries and later used for driving, fed back into the
customer’s domestic network (“vehicle to home”) or sent to the power
grid (“vehicle to grid”), so that any sudden supply bottlenecks can be
alleviated without resorting to fossil energy back-ups from power
stations. This adds further depth to the role of electric mobility as
an intrinsic element of the energy revolution. Its continued spread
serves to lower CO2 emissions both when driving and when
generating electricity.

Fleet test involving 50 BMW i3 models with backfeeding capability.

In addition to devising systems for vehicles and wallboxes that are
able to backfeed power, the Bidirectional Charging Management – BCM
research project is also focusing on the development of technologies
for energy management systems, plus hardware and software for
controlling charging. The legal and regulatory parameters are being
evaluated, too. Nowhere else has such an all-encompassing approach
been actively adopted. All the relevant elements and variables for
normal operation further down the line are being considered from a
holistic perspective and aligned. The project will enter its practical
phase at the start of 2021. A one-year pilot stage will see 50 private
and fleet customers supplied with a BMW i3 with backfeeding
capability, as well as the appropriate charging hardware and
accompanying digital services, so they can test out the customer
benefits of the solutions developed so far and their usability under
real-world conditions. This will create a platform for subsequently
implementing the technology across the board and so integrate electric
mobility into Germany’s power grid.