The Electric Hypergrid
By Fred Pearce
NEW SCIENTIST MAGAZINE
When Arab energy ministers met in Cairo in April, there was one thing at the top of their agenda -- plans for a regional electricity grid that would stretch more than 5000 kilometers from Morocco in the west to the Gulf states in the east. And for Maher Abaza, Egypt's energy minister and the meeting's host, that would only be the start. Abaza foresees a network, with Egypt at its heart, that would give the energy-hungry countries of Europe access to the hydropower of Africa's mightiest rivers. Ultimately, he envisages a worldwide power system that would cut the cost of electricity everywhere. This, says Abaza, represents "the hope for the peoples of the developing world."
Abaza is following in the footsteps of Richard Buckminster Fuller, the maverick American architect and futurologist who was born 100 years ago next week. Buckminster Fuller is remembered chiefly for his geodesic domes, but he also dreamt of continents linked by high-voltage pylons and undersea cables. In the mid-1970s he predicted that the world would one day have a global electricity grid. Now engineers are planning the links that could eventually grow into an international network, distributing power from the rain forests of Borneo and the geothermal rocks of Iceland, the Zaire river and France's nuclear power plants.
In Anchorage, Alaska the talk is of a project to bring hydroelectricity from Siberia to North America through a submarine power line. The Bering Strait, which separates Russia and Alaska, is only 85 kilometers wide and 50 meters deep, but the cable could cost some $2 billion to lay. "We've put eight years' work into engineering, geological and environmental studies," says George Koumal, chairman of the Interhemispheric Bering Strait Tunnel Group, which wants to combine the power link with a railway tunnel. Now is he looking for financing and, in September, comes to London for a fund-raising conference.
Last November, plans were revived to harness up to 37,000 megawatts of generating capacity on the Mekong river, which runs for more than 4,000 kilometers from China, through Burma, Laos, Thailand, Cambodia and Vietnam. Power lines already straddle the river, linking the site of the Nam Ngum dam, near Vientiane, to the Thai border, and construction began this year on another, much larger "export dam" in Laos on the Nam Theun river, a tributary of the Mekong. "It is our hope to build a power grid in the region that will allow the six countries to utilize power most efficiently," says Noritada Morita, director of the Asian Development Bank, which is contributing funds.
The Mekong links may lead to a larger southeast Asian grid. Malaysia and Thailand, two of the world's fastest-growing economies, are planning cross border connections. And, next year, Malaysia is due to begin building a giant hydroelectric plant at Bakun on the Balue river in the rain forest of Sarawak on the island of Borneo. The power station, capable of generating 2400 megawatts, will supply electricity to the mainland through a 650-kilometer cable on the bottom of the South China Sea. Any power that Malaysia does not need will go to Brunei or the Indonesian state of Kalimantan, which between them occupy the rest of Borneo, or to Singapore, says the Malaysian government.
The Himalayan kingdom of Nepal is another remote region with a large hydroelectric potential. It currently has the lowest per-capita energy consumption of any nation on Earth -- the capacity of the national system is just 278 megawatts -- but, according to its Water and Energy Commission, could generate more than 40,000 megawatts of hydroelectricity in its steep valleys. The Arun III hydroelectric project, the first of three dams on the Arun river, which will generate 1500 megawatts, is about to receive funding from the World Bank. This is likely to be followed by another, generating 11,000 megawatts and costing $6 billion, in the Chisapani Gorge just 45 kilometers from the Indian border. And Nepal has plans for more then ten other schemes.
But at present, the world's largest exporter of electricity is Paraguay. The Itaipu dam on the River Parana is the world's biggest power complex, with a capacity of 12,600 megawatts, from where power is fed to Rio de Janeiro and Sao Paulo in Brazil.
Such vast projects appall many environmentalists, who point to the ecological damage they can cause. But not all. U.S. Vice-President Al Gore, who is noted for his environmental concerns, says: "A global energy network makes enormous sense if we are to meet global energy needs with a minimal impact on the world's environment."
Intercontinental electricity grids are the only way to harness the planet's great sources of renewable energy and link them to the centers of population, according to Peter Meisen of Global Energy Network International in San Diego. This non-profit organization is dedicated to promoting Buckminster Fuller's vision of a global grid. "Modern transmission lines can efficiently span up to 6000 kilometers," says Meisen. This is enough to bring power to large industrial centers from hydroelectric sites on the great Arctic rivers, such as the Ob and Yukon, Mackenzie and Lena and tidal power sites in Argentina, China, Australia and India. A global grid could also tap solar power right around the tropics, and the geothermal potential of the "ring of fire" round the Pacific Ocean, in Iceland and in the Rift Valley of Africa.
Modern society is founded on electricity. In 1990, the world's power stations pumped out enough power for every person on the planet to run four 60-watt bulbs permanently. And production is growing fast. Output was up 134 percent from 1970 to 1990, while the global population rose by just 40 percent. That puts electricity well ahead of cars (up 124 percent in the same time), cigarettes (75 percent) or oil (41 percent).
More investment now goes into distributing electricity than generating it, and lines of pylons are extending round the world faster than roads. Four billion people, or around two-thirds of the world's population, are connected to distribution networks. Many began as local enterprises, but more and more have become international, so that today more than 50 nations have electrical interconnections with their neighbors.
Such links can be complex. All grids run on alternating current, but the frequencies and other specifications often differ from country to country, so giant transformers have to be installed at borders These usually convert AC power from one country into direct current and then back into AC to meet its neighbor's specification. This is expensive. A link from Germany to the Czech Republic, completed in 1993, cost $180 million.
International links allow countries to share their generating capacity, and smooth out surges in demand. These can occur at various times of day: during the morning switch-on of factories, or the evening rush for the kettle at the end of a popular TV program, for example. A link can reduce the number of power stations both partners need to build to cope with these peaks. Take the submarine cable linking Britain and France, which came into service in 1986. In England and Wales, average winter demand is 38,000 megawatts, but at peak times the load rises to 47,500. France can help out because it has spare generating capacity and its peak load comes at different times from Britain's.
Mix and match
Long-distance power lines may also allow several countries to benefit from a remote source of cheap power. The world's ten largest power stations are all hydroelectric plants, and most of them are far from their markets. Four are in Siberia, three in remote regions of South America and two in northern Canada.
Power links can (also) be a force for peace. Following the Israel-Jordan peace pact last October, the two states plan to join their grids. A World Bank study last year spelled out the advantages. "As Israel and Jordan have sharply different daily and weekly load peaking patterns, interconnection of their national grids would permit mutually profitable trading between power utilities, and reduce the need for costly back-up capacity for each country," the report concluded.
The Bank also proposed connecting Israel to the Jordan-Egypt link now being built under the Red Sea, and a large hydroelectric project for the rift valley between the Red Sea and Dead Sea, the lowest-lying lake in the world. The scheme would exploit the 400-meter level difference between the two seas by building a canal between them and a hydroelectric power plant on the shores of the Dead Sea. The power station would spur industrial development in the region, and power a desalination works that would supply water to farms and resorts.
During the 1950s, the colonial powers in Africa created several international dams. Besides Mozambique's Cabora Bassa dam, built by the Portuguese, the Kariba dam on the Zambezi has, since its construction in the 1950s, been the mainstay of the interconnected Zambian and Zimbabwean electricity grids. And Ghana's Akosombo dam, conceived by the British and executed shortly after independence, exports power to neighboring Togo and Benin.
The Manantali dam on the upper reaches of the Senegal river in the West African state of Mali was completed in 1987. It was intended partly to generate power for Dakar, the capital of Senegal, more than 1000 kilometers away on the Atlantic coast. But the money ran out and the pylon route to Dakar is (now) no more than a line on the map.
The densest network of links is in Europe. The countries of mainland Western Europe own 14 percent of the world's electricity generating capacity and, for around 50 years, they have been joined by a system of AC links known as the Union for the Cooperation of Production and Transmission of Electricity. The system is connected by DC links to a Scandinavian grid via Denmark, and to Britain by the Channel link.
The East European and Scandinavian grids are both connected to the United Power System, which covers the former Soviet Union and taps Siberia's giant hydroelectric plants. Until 1989, the UPS was a major exporter of power to Eastern Europe. Since then, industrial decline has reduced the trade.
But within Europe, international trade in electrical power is rising fast. During the 1980s, when the amount of power generated increased by half, the trade in electricity doubled. Austria, France and Switzerland export more than 10 percent of their production, while Finland, Italy and Portugal import more than 10 percent of their requirements. Germany exports power during off-peak hours, but is an importer during peak periods, especially in summer.
In North America, there are two prime grids, both cross-border, covering the east and west of the U.S. and Canada. Power from Quebec's hydroelectric plants around James Bay, with a combined capacity of 15,000 megawatts, is brought south on five high-energy power lines into the northeastern U.S. The link provides a tenth of New York City's power. Opposition from the Cree Indians, whose land was to be flooded, recently halted Hydro-Quebec's plans to double the capacity of the James Bay complex. "We regard this as a temporary setback," the giant state enterprise says.
Such regional networks could be the potential building blocks of a global grid. Besides the Alaska link, Russian engineers want to export power from their Siberian dams to the industrial centers of China, Japan and Korea, the top priority being a Russia-China link. The two countries plan a cascade of dams on the Amur river in Manchuria, where it forms the border between them, before cutting across Russian territory and into the Pacific Ocean.
While the superpowers shape up for electrical union, the developing world is looking to transnational electricity grids to promote economic development. In 1993, the African Development Bank agreed to pay for a feasibility study into erecting a 4000-kilometer power line from Zaire to Egypt, passing through the Central African Republic, Chad and Sudan. The idea is to turn the Zaire, the second largest river in the world, into a power source for much of northern Africa.
The idea of a single site powering the whole of Africa may be absurd.
But as electricity demand across the planet grows, the case for ever larger
regional grids becomes stronger. "In the future," says Meisen, "it will
be possible to meet Buckminster Fuller's vision of interconnecting continents."
A global electricity grid is too large a project to be built as a single
endeavor. But, like the emerging worldwide grid of highways, it could happen
Reprinted from New Scientist magazine, vol 147, issue 1995, 08/07/1995, page 388