Where our power comes from
Dusk falls. You flip on the 75-watt light bulb on the ceiling of your front porch. Twelve hours later, the sun blazing strong, you start the coffee, walk out sleepily to pick up the morning paper and flip off that light.
The 12 hours of warmth and safety that light bulb provided on your porch seem so innocent. You can't see any smoke. You can't smell any odor.
Yet the 0.9 kilowatt hours of electricity you just used up do impact the world. The plant that produced that power could be as close as a little "peaker plant" on the outskirts of Elgin. It could be as far away as a dam in Maryland. But far from your sight, far from your nose, some kind of more basic energy had to be roped in and converted into electrical current to keep your bulb burning. And every kind has some negative impact on the world.
Impacts -- both negative and positive -- are gaining increasing attention as efforts are taking place on a variety of fronts to develop renewable energy sources in the Fox Valley and elsewhere.
Amount of effect?
To tell how much negative impact comes from our 75-watt light bulb, we must figure out where the bulb's power came from. With America's power delivery system interconnected in myriad ways, it's almost impossible to say that the electrons flowing into a given house came from this plant or that plant. ComEd spokesman Peter Pedraza said there are 30 generating plants within ComEd's territory and that any of those can feed power into the ComEd grid. If the entire ComEd area runs short, it in turn can borrow power from other utility companies linked to it in an interlocking network called the PJM Grid. To give you an idea of how far PJM extends, its name originally was an acronym for "Pennsylvania, New Jersey and Maryland."
ComEd itself is now purely a power delivery company and doesn't own any of the plants that make its power. But every three months, ComEd averages out what fuels were used to produce the power that fed into its system over the previous year. Extrapolating from ComEd's report for the 12 months that ended last June 30, running just that 75-watt bulb for 12 hours would cause the various power plants that feed ComEd to emit:
• A little over a half pound of climate-changing carbon dioxide. Over a month, that adds up to 19 pounds. Over a year, it may come to more carbon dioxide than your body weighs.
• .003 pounds of acid-rain-causing sulfur dioxide. That adds up to about a pound a year.
• .001 pounds of ozone-causing nitrogen oxides, or about one-third of a pound a year.
Your light also would cause Northern Illinois' six nuclear power plants to create .000006 pounds a day of "high-level nuclear waste" and .00000004 cubic feet of "low-level nuclear waste."
A nuclear state
During those 12 months, ComEd reports, 62 percent of the power it delivered came from nuclear plants. Six are in the ComEd service area and are owned by Exelon Nuclear, which, like ComEd, is a subsidiary of Exelon Corp. Exelon owns more nuclear plants than any other company and Illinois is the most nuclear-power-intensive state.
The closest to the Fox Valley include the nation's first private nuclear plant, the 50-year-old Dresden Generating Station near Morris; Byron Station near Rockford; and Braidwood Station in Will County.
One big advantage of nuclear plants is that they produce no greenhouse gases. The uranium that fuels them comes from the U.S. and can't be cut off by foreign enemies. Exelon says that if all nuclear plants were replaced by coal-burning facilities, it would increase the carbon dioxide going into the air as much as doubling the number of passenger cars.
Nuclear plants also produce power more cheaply than any other type of large-scale power plant; according to the Nuclear Energy Institute, that cost was 1.87 cents per kilowatt hour in 2008, compared with 2.75 cents for coal, 8.09 cents for gas and a whopping 17.26 cents for oil.
Yet no new nuclear plants have been built in the U.S. for decades. That's partly because the radiation-spilling accidents at Three Mile Island in 1979 and Chernobyl in 1986 made people afraid of them. If a plant's controls go awry, or it runs into terrorists or an earthquake, leaking radiation could be disastrous.
Also, the nation still has not worked out a way to take care of the radioactive waste, which will remain dangerous for hundreds of years. So far, the waste is simply being stored inside each plant in water-filled pools and sealed casks. Efforts to develop a permanent storage site in Nevada have stalled.
On the other hand, nuclear plants don't produce huge amounts of such waste. Exelon says that after 50 years, all 10 of its plants "safely store" their spent fuel in "a space equivalent to two Olympic-sized swimming pools."
King Coal
ComEd says 32 percent of its power came from coal-burning plants. This is the dominant form of power in most of the U.S. For example, coal-fired plants feed in 90 percent of the power used by the St. Charles City Electrical Department. Most nowadays burn low-sulfur coal from strip mines in Wyoming.
Coal's greatest virtues are that 1.) it is cheap, making electricity almost as economically as nuclear plants and 2.) it is found in gigantic quantities in our own country. The United States has been called "the Saudi Arabia of coal."
Downsides are that burning it creates more climate-changing carbon dioxide than any other fuel -- 996 tons per million kilowatt hours, according to Exelon, versus 809 tons from burning oil and 476 from burning gas. Although modern coal-burning plants scrub out most of the smoke and sulfur dioxide, some environmentalists also complain that there is "no such thing as clean coal." Poisonous mercury believed to come from coal exhaust has been found in water and soil. And digging up coal creates either ugly strip mines or dangerous underground mines.
And the also-rans ...
• Four percent of ComEd power in 2008-09 came from plants burning natural gas. Most of these likely are small "peaker plants" that go into action only when some special situation makes bigger, less-costly nuclear and coal plants run out of capacity. Burning gas produces less than half as much carbon dioxide as burning coal and poses few other pollution problems. Gas is relatively plentiful inside the United States. But power from gas costs three times as much as power from coal, and five times as much as nuclear.
• One percent comes from "biomass," a vague term that refers to burning or digesting any organic material other than a fossil fuel. No one contacted by The Courier-News seems to know just what is being burned to produce this 1 percent. Because of the way the statistic is compiled, it's possible that most of this is being produced outside Illinois in the other 12 states served by the PJM grid. The only biomass-generating operations known to be operating in the Elgin-Chicago area burn methane gas from the decaying garbage inside landfills. One giant plant in Florida burns fiber from sugar cane plants and lumber waste from home builders.
Burning such materials does emit carbon dioxide. But it doesn't contribute to climate change because, unlike coal or oil or gas, it's not spewing out carbon that had been sitting in the ground for centuries. By simply growing more sugar cane or wood, or turning more paper and food into garbage, the carbon in biomass's carbon dioxide can quickly be taken back out of the air. Thus, biomass is considered a "renewable" fuel.
• One percent comes from hydro power. Again, local officials don't know where this is being done in the Chicago-Elgin area, and that 1 percent statistic may really reflect PJM Grid production in other states. Local businessmen Chuck Emmert and Jack Roeser have proposed setting up small generators along the Fox River.
Hydro power causes no pollution, leaves no waste and theoretically never runs out. But it can be used only at a limited number of locations, and some naturalists claim its dams disturb a stream's animals and plants. Fluctuating water levels also makes dam power unreliable.
• Less than 1 percent comes from burning oil. Oil is just too expensive -- 10 times as costly as nuclear power -- to use for electricity. Oil also is increasingly found mainly in foreign countries and might be better saved to power moving vehicles.
• Less than 1 percent comes from wind power -- so far. But this figure is likely to start going up quickly. Pedraza said ComEd is already connected to wind farms totaling 1,027 turbines, capable of making enough power for 330,000 homes. Free of carbon dioxide and pollution, wind power is limited only by complaints from neighbors about noise and flashing shadows, and by the intermittent nature of wind. But as with hydro and solar, the expense of making electricity this way varies from one operation to another.
"Wind is more expensive," said Glynn Amburgey, head of St. Charles' electric department. Wind generators are smaller than traditional generating plants, he said, so "you don't have the power of scale."
• Less than 1 percent comes from solar power. Largely a phenomenon of more-sunny, warm parts of the country, solar cells can be mounted on a home; and if they make more electricity than the owner needs, the owner can sell the excess to ComEd.
Going green
One thing for certain is that in coming months, renewable energy such as biomass, wind, solar and hydro will become more prominent in ComEd's energy mix. A 2007 state law that set up the Illinois Power Agency to buy power for ComEd requires that by the end of this year, 5 percent of that power should come from renewable sources.
One other thing is sure, too. If you simply replace that 75-watt incandescent bulb with a compact fluorescent bulb, you'll get 75 watts worth of light but use only about 20 watts worth of electricity. Instead of adding 228 pounds of carbon dioxide a year to the air, you'll add more like 60 pounds.
