78 Now We're Cooking!-Mid

Now We're Cooking! FOCUS Question How do energy resources used for cooking affect the environment?

Let's Get Cooking! People have been cooking for thousands of years, Cooking changes the taste, texture, and nutritional content of food. It can also make food safer to eat by killing bacteria. Some cooked food lasts longer or is easier to digest. When people cook, they can combine different ingredients easily. They create delicious new flavors. To cook food means to heat it, which requires energy. For most of human history, there was only one way to cook— using fire. And there was one main natural resource— wood. Now there are many different cooking methods that require different types of energy resources. Each one impacts the environment.

Cooking with Electricity Think about the food you eat. How is it cooked? Your home or school may have an electric stove or oven. It may have a toaster or microwave oven. These appliances run on electricity— energy created by moving charged particles. People make electricity from nonrenewable resources. These resources cannot be replaced after they are used. They include fossil fuels such as natural gas, coal, and oil. Nonrenewable resources also include the uranium used to produce nuclear energy. People also make electricity from renewable resources. These resources include sunlight, wind, and moving water. They never run out. Safety! Be very careful when you cook. Food, pans, utensils, and appliances can become extremely hot and burn you. Never light a fire or cook without an adult.

Nonrenewable resources have a lot of drawbacks. Getting and using them destroys natural habitats. It harms and kills living things. Burning fossil fuels pollutes the air. It gives off gases that cause global warming and make people sick. Producing nuclear energy leaves behind dangerous waste products. Renewable resources cause much less harm to the environment. People build dams across rivers to produce electricity. Fan-shaped machines called turbines make energy from wind. Solar panels use sunlight to make electricity. Using water, wind, and sunlight doesn't give off any air pollution. However, building dams, wind turbines, and solar panels can change the land and water. These changes can harm living things and their habitats.

Cooking with Gas Many stoves, ovens, and grills cook food by burning gas. Natural gas is mostly methane, but it also contains other gases such as propane and butane, which are removed and used separately. Most outdoor grills use propane from a tank. Some camping stoves use a mix of propane and butane from a can. About half the homes in the United States use natural gas for cooking or heating. In cities, underground pipelines transport natural gas to homes and businesses. Rural areas don't have gas pipelines. In these areas, people use liquid propane stored in large tanks. When the liquid is released, it becomes gas for burning.

Natural gas is a nonrenewable resource. It can't be replaced once it's used up. Burning this fossil fuel gives off carbon dioxide, a greenhouse gas that contributes to global warming. It produces less air pollution than burning coal or oil, but getting and using natural gas still harms the environment. People find natural gas trapped in rocks under dry land and oceans. They drill deep holes in the ground called wells through which the gas can flow to the surface. Drilling destroys habitats and pollutes water. Sometimes people use fracking to help gas flow through wells. They force water, sand, and chemicals into wells to crack rocks and release the gas trapped inside. Fracking causes air and water pollution, which harm people and other living things. Word Wise Fracking is short for "fracturing" or "hydraulic fracturing." It refers to the cracking of rocks that occurs during the process.