Rejlers drives innovative electric vehicle charging technology forward

In collaboration with Oslo Municipality and Norway’s Center for International Climate Research, Rejlers has conducted a research and development pilot project into bidirectional electric vehicle charging, with a focus on vehicle-to-building and vehicle-to-home charging.  

Bidirectional electric vehicle charging allows a vehicle battery to both receive and supply power. This turns electric vehicle batteries into mobile energy-storage units that offer economic, operational and environmental benefits. It allows electric vehicle owners to use their car batteries to load shift, for example by supplying their homes with electricity during peak consumption, thereby optimising self-consumption, and even sell electricity back to the grid. This can reduce energy costs, ease grid stress, increase the use of alternative energy sources and limit the need for costly infrastructure upgrades.

The technology is of increasing interest in Norway where electric cars account for approximately 90 percent of new car sales. But while several studies have shown the benefits of bidirectional charging, there is a lack of knowledge about the technical solutions, regulatory requirements and usability.

“When we presented the idea for the project, the municipalitywas curious to find out how mature the technology is and if it could be used within the city as a way of reducing emissions and improving sustainability,” says Lisa Jonsson, Advisor, Electric Power, Rejlers Norway.

Rejlers was engaged to lead the R&D pilot project due to its strong electrical engineering competence, knowledge of electric vehicle charging and smart energy systems, as well as its ability to design, implement and evaluate a full pilot installation. Rejlers also has the capacity to analyse regulatory and electrical-safety aspects.

“We wanted to illustrate the real-world feasibility of deploying bidirectional charging and address challenges such as a general lack of knowledge about the technology, lack of interoperability between cars and chargers and incomplete standards,” says Jonsson. “We also wanted to use the project to assess the technical, regulatory and market barriers, understand user needs and benefits and build knowledge for future energy-flexibility initiatives.”

Rejlers undertook thetechnical design of the pilot project, installation, testing and troubleshooting, coordination of all partners and analysis and documentation of results.

“The physical installation of the pilot project was successfully completed,” says Jonsson. “Due to the early-stage development of both vehicles and chargers, we were unable to achieve full energy flow during testing. The project nevertheless delivered critical insights, validated infrastructure and enabled a clear roadmap for further development. The project also showed how Rejlers is committed to developing energy system innovations, bridging gaps between technology, regulation and practical implementation and supporting our clients to adopt solutions that accelerate the transition to a more flexible and sustainable energy system. It is a concrete example of how Rejlers drives innovation at the intersection of mobility, buildings and the power system.”

The project was carried out in collaboration with CICERO, with contributions from Oslobygg, NAF, Zaptec and Ørnulf Wiig Installasjon.