Two new publications on transmission and distribution system operator coordination as a result of ACS' participation in ISGAN WG6.

The International Smart Grid Action Network (ISGAN) is an international platform for experts to develop and share knowledge and expertise on smart and flexible power grids of the future. ISGAN's national experts come from 26 countries and include engineers, scientists, and industry and policy leaders and decision makers. In collaboration with the International Energy Agency (IEA), ISGAN is committed to identifying advanced technologies and operational concepts. Within thematically clustered working groups, international knowledge exchange is promoted and coordination between stakeholders is facilitated. RWTH participates with ACS and IAEW in working group 6 "Power Transmission & Distribution Systems".

The interaction and coordination between transmission and distribution grids is becoming increasingly relevant, as the decommissioning of large power plants and the expansion of generation based on renewable energies shift flexibility potentials from the transmission to the distribution grid. Consequently, in order to maintain secure grid operation, it is not only necessary, but also potentially economically and ecologically beneficial, to strive for coordinated interaction between transmission and distribution grids. In the future, coordinated interaction could be used to provide ancillary services, to manage grid congestion, or to reduce grid losses.

The advantages and opportunities of coordinated interaction between the transmission and distribution grids are offset by a low level of implementation from today's perspective. ACS and IAEW have developed a discussion paper on the challenges and barriers of implementing coordination concepts. For this purpose, national and international research projects on EU level were analysed in detail and expert interviews with selected contact persons of the research projects were conducted.