Framing the European energy system

High-Voltage Direct Current (HVDC) stands as a globally employed technology for the efficient transmission of substantial electrical power quantities. To align with European objectives of seamlessly integrating renewable energy sources and phasing out thermal power plants, a rapid expansion of HVDC projects is imperative. Given that current HVDC projects operate as point-to-point connections, the evolution of meshed DC grids becomes essential. This whitepaper delves into the enduring role of HVDC and meshed DC structures, particularly Multi-Terminal, Multi-Vendor (MTMV) HVDC grids, within the transformative landscape of the European energy system.

In a collective commitment to transform the EU into a climate-neutral entity by 2050 and reduce carbon emissions by at least 55% by 2030, EU member states recognize the pivotal role of HVDC technology. The pressing need for a massive expansion of Renewable Energy Sources (RES) generation capacity, notably offshore wind power, is highlighted, with the North Sea countries setting ambitious targets of at least 120 GW by 2030 and 300 GW by 2050 in the Ostend Declaration. HVDC cable transmission emerges as the primary technology for bringing offshore wind power to European shores, tapping into an estimated potential of 380 GW in northern European waters.

The Ostend Declaration targets necessitate a tenfold increase in installed capacity from the present to 2050, underscoring the magnitude of offshore wind and HVDC development. This growth trend is anticipated to persist, potentially escalating in the coming years. HVDC’s significance extends beyond offshore wind power evacuation, encompassing cross-country interconnections for energy trading. Onshore HVDC, both through overhead lines and underground cables, plays a vital role in long-distance transmission and cross-country interconnection, aligning with the needs identified in the Ten-Year Network Development Plan (TYNDP) of ENTSO-E.

Another crucial aspect of HVDC’s role is its ability to replace certain grid-stabilizing functionalities of existing AC assets, such as the inertia provided by synchronous generators. When considering all these use cases and factoring in current HVDC growth rates, projections suggest a potential total HVDC-based transmission capacity approaching 1 TW by 2050.

Recognizing the necessity for a robust European transmission grid to integrate renewable power generation, balance variable energy outputs, and accommodate the anticipated rise in power consumption, the question arises about the need for an HVDC “supergrid” spanning multiple European countries. Visions for the future European grid vary, with an incremental approach gaining traction over earlier top-down planning for a large-scale HVDC grid. The emergence of the first multi-terminal HVDC systems reflects a pragmatic strategy, allowing for gradual extensions and the realization of meshed MTMV HVDC grids. This approach contrasts with the initial pursuit of an extensive HVDC grid covering regions like the North Sea.