In countries around the world, there is a growing need to move what is expected to be significant amounts of wind, solar and hydro-generated electricity from sparsely populated remote regions to the cities where demand is great.

This has ignited a quest for new high-voltage and ultra-high-voltage transmission systems that can carry more electricity longer distances. And to be sure these systems work properly, there is a growing need for test facilities to evaluate and certify the new transmission products and technologies.

Certainly, the idea of ultra-high-voltage transmission systems is not new. There have been many notable deployments in Russia and Japan, and experimental systems are being tried in several countries.

But there is now added urgency to deploying such systems. "Our electricity is going to be generated farther away from its use," said Bill Babcock, director of the utilities practice at the consulting firm LECG. "You have losses moving power long distances, so if you are putting in a new system, use the best or most efficient transmission technology available."

That's the reason for the new interest in new ultra-high-voltage transmission systems. Their desirable properties are a good match for anticipated new generation scenarios. AC and DC ultra-high-voltage transmission systems have rated voltages of 1,000 kilovolts alternating current, 800 kilovolts direct current or more. And the higher voltage systems can carry more power longer distances with less loss than their lower voltage counterparts.

These capabilities nicely complement new generation worldwide. Countries such as China and India are expected to vastly increase power generation of all sorts. Europe, Africa, and the Americas are expected to add significant renewable capacity to meet mandates that, in many countries, demand that 20 percent of the power come from renewable sources. In the United States, it's not just getting solar from the southwest to New England or wind energy from the Dakotas to New Jersey, there is also a desire to get hydro power from Quebec to Boston and wind power from sparsely populated Hawaiian Islands to the population centers.

In China, vast hydroelectric power resources in the west and coal plants in the northwest are expected to help meet the country's booming demand for electricity. That demand is and will be primarily in urban areas in the east and south. Ultra-high-voltage transmission systems offer lower power loss over great distances, thus making a great fit for the situation.

"China's explosive load growth is a classic case of generation in one region, load center in another," said Wade Malcolm, transmission and smart grids director, utilities industry group at Accenture.

Keeping Pace

To address this issue, the State Grid Corporation of China plans to invest more than $14 billion in the next three to four years to build and expand an ultra-high-voltage network. Longer-term, the country anticipates investing about $88 billion in ultra-high-voltage development between now and 2020.

Through the work of the State Grid, currently one ultra-high-voltage transmission circuit is operational and three more are under development.

To support the higher voltage transmissions requires new switchgear. To that end, about three years ago the State Grid Corporation of China set out to demonstrate the feasibility of AC power transmissions at ultra-high voltage.

Over a two-year period, switchgear provider ABB, working with Chinese technology partner Xian Shiky High Voltage Electric, designed, tested, and commissioned gas-insulated switchgear for the project. Pushing the envelope further, ABB more recently commissioned switchgear rated to handle more than 1 million volts. According to ABB, "The equipment has a switching capability of 6,900 megawatts, which means it can turn power equivalent to the average electrical consumption of Switzerland, a country with more than 7 million inhabitants, on or off within milliseconds."

One point that has emerged in this work is the need for testing and certification to keep pace with the new products and technologies. "The move to higher voltage transmission impacts transformers, breakers, and other transmission and distribution equipment," said Mike Bahrman, ABB's high-voltage and ultra-high-voltage transmission expert. "As we go to higher frequencies, there are all sorts of new standards, testing standards, and test requirements."

He pointed out that testing is really a people business, meaning technicians must be competent, possess special skills and know the certification process.

To help meet the demand for the testing and certification, KEMA opened a new lab in the Netherlands last year. At the lab's opening, Peter Bus, managing director of KEMA's transmission and distribution testing services, said, "We expect the lab to play a major role in helping companies worldwide make strategic decisions about infrastructure development."

The new facility will function as an independent laboratory for testing and certification of high- and medium-voltage components used in electrical infrastructure. From the lab, KEMA will issue type test certificates and reports for tests on cables, cable accessories, insulators, power transformers, instrument transformers, switchgear, gas-insulated switchgear and panels.

Although the move to high-voltage and ultra-high-voltage transmission seems to be a sure thing, other scenarios might or should be considered. For one, alternative technologies might play a role. For example, several transmission system demonstrations and trials are going on around the world using superconducting cables. Such cables offer very low loss and very high capacity. They are likely to find use in urban settings such as New York City, where they would carry electricity shorter distances than the ultra-high-voltage circuits.

And, although they are not a major factor now, conservation and energy efficiency efforts could help reduce power demands. However, few think the reductions would be significant enough to negate the need for the new ultra-high-voltage systems.

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