The power grid must be expanded to meet the demands of the green transition. With new EU regulations on the phase-out of the insulation gas SF₆, this means that future grid expansion must be carried out using completely new switchgear technologies and new insulation gases. It is vital that this expansion proceeds without compromising the grid resilience or the equipment lifetime.
The NEMEGIS project will collect and report existing user experiences from SF₆ free switchgear operating in the Norwegian and European power grid.
The project will also carry out experimental and theoretical studies of the new insulation gases to obtain an improved fundamental understanding of their properties, both in a short- and long-term perspective. The gases will be tested both in their “as new” state and after accelerated ageing in the laboratory.
Background
During the green transition, distribution and transmission system operators (DSOs and TSOs) are intensively maintaining and expanding their grids to meet the increasing demand for electrical power. As an increasing number of utilities run on electric power, it is imperative to ensure security of supply. Switchgear are essential in this task, as they reroute the flow of energy and interrupt fault currents.
Most switchgear are electrically insulated using sulphur hexafluoride (SF₆) gas, which is the most potent greenhouse gas known. It has a global warming potential (GWP) of 24 300, an atmospheric lifetime of ~3200 years, and is the largest source of direct greenhouse gas emissions (scope 1) for most transmission system operators.
Consequently, the European Commission has set deadlines for installing new SF₆ based switchgear, which are rapidly approaching. From 2026, all new switchgear ≤24 kV must be SF₆ free. For high voltage (HV) ratings, the closest deadline is 2028 for switchgear ≤145 kV, and then further in 2032 for all switchgear at all voltage levels (with a few exemptions). This means that future power grid expansion will be carried out using completely new switchgear technologies, and it is vital that this expansion proceeds without compromising the grid resilience or the equipment lifetime.
KSP NEMEGIS builds on the previous KSP-project New gases for GIS.