Super grid
A super grid (or supergrid) is a very large electricity network that connects countries or even continents. Its goal is to move huge amounts of electricity over long distances, such as from sunny deserts or windy seas to cities far away. These grids often use high-voltage direct current (HVDC) lines because they can carry power over thousands of kilometers with very little loss—about 1.6% per 1,000 km[1].
Super grids help balance energy supply by sharing power across regions. If it's cloudy in one place or calm in another, power can still flow from areas with more sun or wind. This makes renewable energy more reliable and helps reduce greenhouse gas emissions.
History and ideas
The idea of super grids goes back many decades. In the 1950s and 1960s, planners in the United States and the United Kingdom explored ways to share electricity across long distances. One early example is the Pacific DC Intertie, completed in the US in 1970, which delivered power from the Pacific Northwest to Southern California using HVDC technology.
Over time, the term "supergrid" has also come to describe parts of national grids designed for very high voltages (over 200 kV), such as in Britain.
How the technology works
Most super grids use HVDC, which sends electricity in a steady, single direction. Compared to traditional alternating current (AC) systems, HVDC is much more efficient for very long distances. It also allows better control over the flow of power between connected grids.
Some regions consider high-voltage AC (HVAC) for super grids, but HVAC systems become inefficient and costly over long distances. In a few cases, hybrid systems or new experimental technologies—like superconducting cables cooled with liquid hydrogen—are being studied for even better efficiency in the future.
Examples around the world
Several regions are planning or building segments of super grids today:
- Europe is working toward a pan-European super grid. Projects include undersea cables linking Scandinavia, the Mediterranean, and the British Isles, as well as land lines between major countries. These links aim to share power across borders and support renewable energy use in the whole region.
- China has developed ultra-high voltage DC lines that send electricity over 3,000 km—from the west to Shanghai—carrying up to 12 GW. These lines are essential for balancing regional differences in energy production and demand.
- Asia has proposed the Asian Super Grid, which would link China, South Korea, Japan, Taiwan, India, Russia, and Mongolia. Its aim is to share renewable power across all of Asia and reduce outages and waste.
Benefits of a super grid
Super grids offer several key advantages:
- They reduce energy losses, making long-distance power delivery more efficient and cost-effective.
- They smooth renewable energy, because when one area has low solar or wind output, another region likely has more, ensuring a steady supply.
- They lower costs, by sharing power from the most efficient sources across regions and avoiding expensive energy storage or backup systems.
Challenges and outlook
Building super grids faces big challenges:
- Politics and regulation: Projects require cooperation between many countries, each with different rules.
- Public resistance: Long power lines often face opposition over lands and landscapes.
- High costs: Building large HVDC infrastructure is expensive and complicated.
Still, the benefits make super grids appealing in the push toward clean energy. Today’s efforts in Europe, Asia, and China show growing progress toward larger, smarter energy networks. As more renewable energy comes online, super grids offer a promising way to connect it across regions, improving reliability and cutting climate impact.
Super Grid Media
A proposed 765 kV AC transmission grid designed to carry 400 GW of wind power to cities from the Midwest at a cost of $60 billion.
