Dear EarthTalk: I've been hearing that wind power is going to play a significant role in our energy future. What's the story?
—Dorothy Raffman, Norwalk, CT
Wind energy is zero-emissions energy, a renewable resource that many environmentalists and alternative energy proponents feel is one of our last, best hopes for staving off devastating climate change. According to the American Wind Energy Association (AWEA), the average wind turbine can prevent the emission of 1,500 tons of carbon dioxide each year.
Globally, wind energy has grown 500 percent since 1997. In 2003, 8,133 megawatts of wind-generating capacity were installed worldwide, according to a recent joint announcement from AWEA and the European Wind Energy Association (EWEA). This brought the world's total wind power generating capacity to 39,294 megawatts, enough to power 19 million European households, according to EWEA. World wind leaders include Germany, the U.S., Spain, Austria and India, each with more than 1,000 megawatts. A number of other countries, including the Netherlands, Italy, Japan and Great Britain, are nearing the 1,000-megawatt mark.
In the United States, there are now wind energy installations in almost every state west of the Mississippi, and in many Northeastern states. California leads with more than 2,000 megawatts of installed wind energy, followed by Texas with nearly 1,300 megawatts. In total there were nearly 6,400 megawatts of wind power in the United States as of January 2004, enough to power 1.6 million U.S. homes, and up 50 percent from the installed capacity in the U.S. at the end of 2001, says AWEA.
Offshore wind has enormous growth potential as well. Germany, for instance, recently finalized an agreement to build a 350-megawatt project (with 70 five-megawatt turbines) anchored on the ocean floor off the island of Rügen. Here in the United States, in Massachusetts, the Cape Wind Project hopes to construct a $700 million, 420-megawatt, 130-windmill development that would stretch for five miles off Cape Cod, though it has drawn opposition from some residents, as has the German project, for fears that it will be an eyesore and could harm migrating birds.
Dear EarthTalk: Which are better for the environment, disposable or cloth diapers?
—Barbara Fritts, White Lake, MI
The "disposable versus cloth" debate has raged among environmentalists for years. Non-degradable disposable diapers can sit for decades, even centuries, in landfills and require thousands of tons of plastic and hundreds of thousands of trees to manufacture. However, the water and chemicals used to clean cloth diapers, and the fossil fuels diaper services consume to transport them, suggest that their relative environmental impact could be a wash.
However, modern advances in water- and energy-efficiency in washing machines and dryers have reduced the environmental impact of diaper laundering. Concerned parents should also consider the issue of sewage. The urine and feces in disposable diapers enter landfills untreated, possibly contaminating the ground water supply. Whether cloth diaper waste is flushed down the toilet or removed in the washing machine, that dirty water will enter a sewer system and, most likely, a wastewater treatment plant.
Also, John Shiffert, executive director of the National Association of Diaper Services (NADS), points out that the chlorine byproduct dioxin, a carcinogen, has been found in trace amounts in disposables.
Those concerned about the environment who want the convenience of disposables can try Nature Boy and Girl, which makes a competitively priced, cornstarch-based diaper that can be composted. Using flushable cloth diaper liners, made by Tiny Tush and other companies, means only the thinnest—and messiest—part gets thrown away. Parents who want to use cloth diapers can hire a cleaning service to do the dirty work. Their numbers have rebounded in recent years. Check the yellow pages, or contact NADS to locate a service in your area.