Arriving in Copenhagen by sea, the first thing travelers see of Denmark is a row of 20 enormous wind turbines gently spinning above the waves nearly two miles from shore. Completed last December, the Middelgrunden Wind Farm is the world’s largest offshore wind power facility. Its wind machines, each with blades 100 feet long, together generate 40 megawatts of electricity, enough to power 32,000 households in Denmark’s bustling capital. It produces no pollution or greenhouse gasses and was designed to have minimal environmental impact on the marine life of the Oresund, the chilly sound connecting the Baltic and North Seas.
Middelgrunden is a fitting symbol for Denmark, a nation of five million that has emerged as a world leader not only in wind power, but also in the effort to create a more sustainable society. Well-maintained bicycle paths complete with road signs and traffic lights connect towns and cities, often running parallel to rural highways.
Recycling centers are ubiquitous, helping Denmark boast that half of its waste is recycled. The country generates 13 percent of its electricity from wind and plans to raise that figure to nearly 50 percent by 2030. Authorities in central Copenhagen have deployed 2,000 free bicycles in public squares and train stations, while a nationwide tax on automobile purchases more than tripled the cost of buying a car. Ninety miles to the southwest, on the windy island of Aero, hundreds of homes get their heat and power from Europe’s largest solar power station.
Across the country, farm manure and kitchen garbage are delivered to biogas plants that produce uniform fertilizer and a methane fuel burned cleanly at power plants. "Planning for the environment has always been popular in Denmark," says Christian Matthiessen, a geographer at the University of Copenhagen, who points to public opinion polls showing that most Danes say environmental protection is more important than economic growth. "We’re an agricultural nation where nobody lives more than 30 miles from the sea. The environment has always played a role for everybody."
Twenty years ago, when industry managers in the small industrial town of Kalundborg realized they were facing a potential water shortage, they got together to see how they might better share resources. What they came up with not only solved the water shortage, it also inspired an entirely new field of scholarly research that promises to revolutionize the way industrial systems are planned and operated.
Starting with water, Kalundborg’s key industrial firms have been finding ways to turn one firm’s waste products into another’s raw resources. Today, waste heat from the local power plant warms fish farms and most of the area’s homes and businesses, while excess steam is piped to a neighboring oil refinery and biotech company. Air scrubbers on the power plant’s smokestack turn sulfur dioxide into gypsum, which is then sold to a neighboring plasterboard factory, which dries it in flare-gas-fired kilns and turns it into wallboard. The power station uses the refinery’s wastewater for cooling and to operate the scrubbers. Sludge from the county’s wastewater treatment plant is sold to a local soil remediation company, which uses it to grow the pollution-eating bacteria that clean contaminated soil brought from across Denmark. Fly ash from the power station is sold to cement makers or firms that extract valuable metals from the wastes.
The companies have all saved money in the process while reducing pollution and slashing consumption of water, energy and other resources. By investing approximately $75 million in this "industrial symbiosis" to date, the firms are saving about $15 million a year.
"We’re all making money from this," says Per Holmgard, manager of Kalundborg’s power station, which has electric cars parked in its lot. "We have a bit of difficulty understanding why the rest of the world isn’t doing it." Kalundborg has since inspired researchers in "industrial ecology," which looks for ways to pattern industrial systems after natural ecosystems, where one organism’s waste is another one’s food.
When the oil shocks of the 1970s forced many oil-dependent nations to rethink their energy strategies, the U.S. and many European countries invested in nuclear power and synthetic fuels. But Denmark turned to an energy source that had been powering its agricultural economy for centuries—wind power—providing tax and investment incentives for the industry’s pioneers.
Today, Denmark completely dominates the booming wind power industry, which was the world’s fastest-growing source of electricity in the 1990s. Danish companies supply more than half the turbines now in use worldwide, making it one of the country’s largest exports and employing more than 12,000 people. Wind turbines dot the Danish countryside like gigantic pinwheels, and many are owned by cooperatives of local residents. Wind power doesn’t release carbon dioxide into the atmosphere, so it has helped Denmark meet its commitment to slash greenhouse gas emissions by 21 percent from 1990 levels by the end of the decade.
"We’ve been able to show the world that wind energy can let you de-carbonize your economy without hurting economic growth," says economist Christian Kjaer of the Danish Wind Turbine Manufacturers Association in Copenhagen. "In certain [foreign] markets, we’re able to compete with existing power sources without any subsidies."
At the same time, Danish energy planners are slowly replacing the country’s large, centralized power stations with a broad network of small, local power generators. This is expected to reduce losses from long-distance transmission and allow rural communities to heat their homes with the residual heat from their local power stations. "We believe smaller-scale power systems will be more flexible and efficient," says Knud Perdersen, deputy director of the Danish Energy Agency. "It’s good for the environment and gives us a more robust economy, so why not do it?"