The Energy Transition Is a Grid Transition

The energy transition is often described in terms of generation: wind turbines, solar parks, batteries, hydrogen, nuclear. But from the perspective of someone who has spent fifty years working on power systems—much of that time devoted to overhead transmission lines—I am convinced of one essential truth: the energy transition will succeed or fail on the strength of our grids.

Electricity is the backbone of modern society. According to the IEA World Energy Outlook, global electricity demand is expected to rise by 6,000 to over 7,000 TWh already by 2030, and by 2050 demand in a net-zero scenario could be 150% higher than today. At the same time, around 20% of the world’s population still lacks access to electricity. We are therefore facing a dual challenge: decarbonize existing supply while expanding access to billions.

If we take net-zero ambitions seriously, global electric power demand in 2050 could reach 25,000 to 40,000 TWh. Today’s installed capacity though of all energy sources combined is roughly 10,700 GW, of which only a fraction is carbon-free. The implication is staggering: we would need to add the equivalent of more than 1,000 large 1,000 MW power plants every year until mid-century! Most of this new capacity will be wind and solar, complemented by nuclear. Fusion, despite its promise, is unlikely to contribute at scale before mid-century.

The Grid Is the Real Bottleneck

But generation is only half the story. The real bottleneck is transmission. The global transmission grid—largely overhead lines—amounts to approximately 8 to 10 million circuit-kilometers. To accommodate the energy transition, we will need an additional 1.5 to 2.5 million kilometers of new lines, including up to 500,000 kilometers of HVDC; this is more than the distance of the Earth to the Moon! On top of that, 40 to 60% of the existing network—3 to 6 million kilometers—will have to be refurbished or replaced by 2050. In total, the requirement for high-voltage overhead lines alone could reach 4.5 to 8.5 million kilometers, not to mention investments in distribution. This is an engineering effort of historic proportions. It is comparable to rebuilding the global grid while keeping it fully operational.

And we must do this under increasing stress. Grid operators around the world are already concerned about extreme threats. Surveys show that blackout risks, seismic events, cyberattacks, snow and ice storms, floods and physical security incidents rank among the most actively evaluated scenarios. Climate change is further amplifying weather-related risks, while digitalization introduces new vulnerabilities. The Iberian blackout case demonstrates both the fragility and the resilience of modern systems: rapid restoration was possible thanks to interconnections, restart protocols and robust SCADA (Supervisory control and data acquisition) and protection systems. Which shows, that resilience is not an abstract concept—it is a daily operational necessity.

Technology Helps But Infrastructure Delivers

Digitalization and artificial intelligence will increasingly shape system operation. AI can enhance forecasting, optimize dispatch, detect anomalies and support decision-making. Yet AI is not a substitute for physical infrastructure. Algorithms cannot compensate for missing transmission corridors or aging conductors. Software requires hardware.

One fundamental principle has guided my professional life, which has become more evident in the age of the energy transition: there is only one grid. Generation, transmission, distribution, consumers, prosumers, storage and sector coupling are all part of an integrated physical system governed by the same laws of physics. We cannot electrify transport, industry and heating without massively reinforcing distribution. We cannot integrate large shares of variable renewables without stronger interconnections. And we cannot maintain public trust without reliability.

Public acceptance will become a decisive factor. Building millions of kilometers of new lines and grid infrastructure will require social dialogue, environmental sensitivity and transparent planning. Equally important is investment. Grid investments will need to double by 2030 and continue rising thereafter. This requires stable regulatory frameworks and long-term political commitment. Delays in permitting and inconsistent policies are among the most serious threats to timely implementation.

Finally, we must invest in people. The scale of the transformation demands engineers, technicians, researchers and operators in unprecedented numbers. Knowledge transfer between generations is essential. We must attract young talent and provide them with opportunities to contribute to one of the most meaningful engineering challenges of our time.

The energy transition is not optional. Rising CO₂ concentrations and global temperature trends leave no doubt about the urgency of decarbonization. But the transition will not be achieved through slogans or isolated projects. It will require a systemic approach grounded in engineering reality.

In my view, the defining challenge of the coming decades is clear: we must design, finance, permit and build a resilient, interconnected, intelligent global grid—at a pace and scale never seen before—while maintaining reliability every single day.

The future belongs to electricity. But whether that future is sustainable, secure and equitable will depend on the grid.