Global warming concerns, government policies, and money-saving efficiency benefits have spurred clean energy systems to spring up all over the world. But a giant wind farm in the middle-of-nowhere North Dakota doesn’t do much good if there aren’t transmission lines to connect the power with the more populated areas that need it.

Europeans are facing similar distribution and reliability issues with their burgeoning renewable energy growth, and some see a continent-wide grid as the solution. Dr. Jurgen Schimd of ISET, a renewable-energy institute at the University of Kassel in Germany, says a transmission system that stretches across Europe is the answer. It could, for example, move electricity generated from a Spanish wind farm to the Netherlands where the wind is not blowing.

Norway is key to Dr. Schmid’s plans, as the Scandinavian nation is well-supplied with hydroelectric plants that can store energy from sources like the wind. For instance, the wind power is used to pump water up into the reservoirs that feed the hydroelectric turbines, so the power is “on tap” when needed. According to Dr. Schmid, even if the wind died and wind farms shut down all across Europe, Norway’s hydropower would leap to action and fill in the gap for up to four weeks.

This continent-wide transmission system for renewable energy has also sparked a renewed interest in direct current (DC). Over 100 years ago, when power grids covered shorter distances, alternating current (AC) transmission was favored because it loses less electricity than DC. However, as transmission lines have grown longer, high-voltage DC lines now suffer lower loses than AC. So using a DC transmission system would allow electric grids to be restructured more efficiently, losing less energy while transmitting it from Point A to Point B.

Some nations have already started work on a DC transmission system. A group of Norgwegian companies have begun building high-voltage DC lines between Scandinavia, the Netherlands, and Germany. An Irish wind power company called Airtricity proposes what it calls a Supergrid that would link offshore wind farms in the Atlantic Ocean with customers in northern Europe.

The electric grid in the U.S. is in sore need of an upgrade, and we should consider ideas that utilize the different forms of renewable energy abundant across the country (like hydroelectric in the Northeast, wind in the Midwest, solar in the Southwest). It’s a combination of these renewable sources – along with crucial upgrades in efficiency – that will provide a clean, reliable network of distribution in the 21st century.

Thanks to Working Dad at Housekept for the tip.

The Economist
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