Powering cities from afar: Can ultra-high-voltage lines fuel the renewable future?

Delivering dependable, clean power over long distances is a major challenge for countries as cities expand and energy demands rise. Ultra-high-voltage (UHV) gearbox technology has been adopted by China, which has built enormous power highways to transport energy from rural, resource-rich regions to crowded cities.

This bold method, sometimes referred to as the “bullet train for power,” is a pillar of China’s renewable energy plan, but it has complicated logistics, high costs, and environmental trade-offs. Is a more regional strategy the solution, or could UHV lines be the secret to a sustainable future?

The arguments

China’s energy system is changing thanks to its UHV lines, which make it possible for large areas to share electricity and open the door for the integration of renewable energy sources. Nevertheless, the cost of relying on UHV is high; an estimated $222 billion has been spent on 33 active lines and more are being built. Furthermore, in order to satisfy dependability requirements, UHV lines frequently transport coal-based electricity despite their potential for renewable energy. Only 27% of China’s UHV-transmitted energy in 2022 came from solar and wind; the majority of the renewable mix was hydropower, which has negative environmental effects such upsetting ecosystems.

Furthermore, the requirement for long-distance electricity imports may decline if cities like those on China’s coast develop their offshore wind and nuclear capacities. Despite their efficiency, mega grids run the risk of experiencing widespread blackouts if one part fails, as seen in the 2003 North American blackout.

The Balancing Act

Although UHV technology is an essential component of China’s energy arsenal, experts advise that it should be used in conjunction with community energy projects and local microgrids as part of a more comprehensive strategy. This combination may minimise expenses, lessen hazards, and encourage local participation in the energy transition. As energy expert Antony Froggatt points out to BBC,  engaging communities in power generation—through rooftop solar and neighborhood wind—is as vital as building cross-country supergrids.

The facts

China has developed ultra-high-voltage (UHV) transmission technology, which enables electricity to be transported over long distances with little power loss, in an effort to meet the country’s rapidly increasing need for electricity.

A prime example is the 1,900-kilometer-long Xiangjiaba-Shanghai line, which links a hydropower source in southwest China with the vibrant metropolis of Shanghai. These lines, known as the “bullet trains for power,” are crucial for delivering energy from isolated regions with abundant hydro, coal, wind, and solar resources to crowded urban areas.

While Europe and Australia are investigating long-distance high-voltage cables for importing renewable power, other countries, such as Brazil and India, are using UHV technology on a lesser scale. By moving electricity from areas with advantageous solar and wind power, the expanding UHV network helps balance volatile renewable energy.