IEA Enard: - International collaboration on developments in transmission systems R&D

This paper reports the ongoing activities in IEA ENARD’s Annex IV “Transmission Systems”. The Annex was formally adopted by the ENARD Executive Committee in September 2008, with the aim to establish a long term vision for developments in transmission systems beyond 2020. On this background the objective is to address the main barriers towards the necessary development of transmission systems and to identify the most promising solutions related to the various operational, planning, technological, and market aspects, including the need for development and application of new methods and tools. Finally the Annex is expected to address the specific R&D activities needed as a result of the vision. There is a need for new solutions to deal with variable and less controllable generation and to cope with the distance between generation and the main load centres. The solutions rely on development of transmission capacity and storage, taking advantage of further technological developments such as VSC-HVDC. In order to enable necessary investments it is equally important to establish a suitable regulatory framework and market design, allowing close coordination among the involved entities and reducing the investment risk. Further, more refined methodologies and tools need to be adopted to identify the best options for grid expansion. The future development will require significant changes in the way power systems are operated and controlled. A main barrier is the uncertainty related to management of reserves and balancing control, ranging from secondary control in the minute range to tertiary control and intra-day markets. A key message is that there is a need for a better understanding of the various challenges related to balancing the increasing variability in power generation and load demand on this time scale. New tools and analysis techniques must be developed to properly address these issues.