The use of fossil fuels and the emission of greenhouse gases (GHG) into the atmosphere must be minimised as fast as possible to reach a climate-neutral society by 2050. A vital prerequisite of the de-carbonisation is the rapid growth of renewables. In 2050 more than 60 % of electrical power is expected to come from wind and solar, both significantly more remote located than traditional thermal power generation. To achieve this, efficient grid-integration of renewables across Europe and globally requires the development of high-power transmission systems and components, and more specifically Medium Voltage DC (MVDC) and High Voltage DC (HVDC) switchgear. In existing grids MVAC and HVAC switchgear is filled with the insulation gas SF6, the world's most potent GHG with a global warming potential (GWP) of 24 300. SF6-emissions due to leakages during gas handling or defective sealings / compartments represents a significant part of the grid owners' total GHG emissions. MISSION project will develop and demonstrate three SF6-free products as key-levers for climate neutral power transmission based on the requirements defined by TSOs, filling critical gaps in future hybrid ACDC grids: 1. SF6-free HVAC circuit breaker will be developed and type tested by Siemens Energy and installed and demonstrated by Statnett in Norway and RTE in France reaching TRL 8, 2. SF6-free HVDC GIS will be developed and type tested by Siemens Energy in Germany reaching TRL 8, 3. MVDC circuit breaker will be developed and tested in relevant environment by G&W reaching TRL 6. In addition, MISSION will determine technical properties of different SF6-alternatives for application in AC and DC switchgear for high and medium voltage operation. MISSION will contribute to enable emission-free energy transmission and switchgear technology transition for a resilient and sustainable future electric grid.

To unlock multi-vendor HVDC grids and foster the transition of the European energy sector at large scale, InterOPERA proposes a coordinated approach between a diverse, high-level group of industries at the forefront of RES development and grid management. 4 HVDC vendors, 8 TSOs, 2 wind turbine vendors and 3 wind park developers bring their industrial knowledge and practical abilities to make future HVDC systems mutually compatible and interoperable by design, and to improve the grid forming capabilities of offshore and onshore converters. Foreseen and planned HVDC projects will be analysed to define a demonstrator case study. The resulting system-level design will be usable as a guidance to coordinate offshore network planning. This new way of framing the European grid architecture and topology will ensure forward compatibility for future seamless system expansion. Interoperability of control and protection systems will be de-risked through the execution of all necessary activities concurring to the implementation of a real-time physical demonstrator. Concrete results will be delivered through this practical work: detailed functional specifications for each subsystem, standardised models, simulation platforms and interaction study processes, multi-vendor cooperation agreements. Those frameworks will be generalised into operational and strategic tools available to all European stakeholders for the development of multi-terminal HVDC grids that will enhance offshore wind development and integration. Solutions for multi-vendor project procurement, compliant with existing and future regulations, standards and laws, integrating the technical specifications and interoperability assessment tender stages, will be provided to pave the way to the first real-life projects in Europe. External stakeholders will be involved in two-way consultation workshops to maximise the uptake of InterOPERA’s key exploitable results. Recommendations to grid codes and standards will be issued.