Yesterday, about 40 miles upstream of Natchez, Mississippi we passed the tall, wide, steaming cooling tower of a nuclear power plant and we got to talking about electricity production. As we travel downstream, we pass tree-lined banks and sandy shores which provide critical habitat for critters that live along the river: bald eagles, deer, turkeys, woodpeckers, coyotes, muskrats, dragonflies, snakes, bobcats, insects, beavers, and more. Under the water, there is a wide variety of fish species, as well as mussels, crawfish, and other aquatic life who contribute to the diverse river ecosystem.
One animal species that relies on the Mississippi River is the human. The river's rich biodiversity helps support healthy human life from source to sea. The Mississippi provides drinking water for 18 million people, a shipping route for commodities such as coal and grain, and water for industry. Importantly, many electricity-producing power plants exist along the river. People rely on electricity for a variety of purposes: lighting homes, cooking, charging devices, and lots more. In what ways do you use electricity? Have you experienced a time when electricity did not work or it wasn't available?
There are many ways to create electricity. Throughout our journey we have seen coal and natural gas fired power plants as well as power plants that use nuclear energy. Cooling with water is one step in the process of creating electricity, which is why many power plants are located adjacent to bodies of water. Power plants use water to produce steam, which moves a turbine, and then they dispose of that water by putting them back into lakes or rivers nearby. When the water re-enters the river it is warmer than the river water. The fish and invertebrates (bugs) that live in the water are adapted to specific temperatures. Warm water from the power plants changes the water temperature and therefore interrupts the lives of species that rely on a specific range of water temperatures. Since the food web is interconnected, this affects not only the plants, fish, and invertebrates that live in the water, it also affects the birds that eat the fish, and the animals that eat the birds, and so on. The water temperature increase due to water entering the river from electricity production is harmful to water quality and therefore to all life that depends on the river.
What this means is that you can help protect the plants and animals near your home. Depending on where you live and where your electricity comes from, you help protect the water quality of the Mississippi River, or a different body of water. There are many ways you can conserve electricity: turn off the lights behind you when you leave a room, limit the amount of time the refrigerator or freezer door stays open, turn the water off while brushing your teeth (it requires electricity to run water!), or line dry your clothes rather than in a drying machine. By conserving energy, you are directly protecting the health of the environment around you, and in turn, your own health. What are other ways that you can reduce electricity use? Where does the electricity that supplies your home come from? What about your school? What type of fuel is used to create electricity? Where does that fuel come from? What are ways that energy producers can mitigate the effects of electricity production on water quality?
If you are interested in other ways to conserve energy use, check out the resources at the Minnesota Energy Challenge (http://www.mnenergychallenge.org/For-Kids.aspx) Their mascot, TOLBY (stands for Turn Out Lights Behind You) the firefly, is full of ideas! Also, if you live in Minnesota, he could come and visit your classroom!