AK Target grades: 3-5 AK GLEs: Reading [3] 1.4.1 [4/5] 2.4.1 [3] 1.6.1 [3] 1.6.2 [4/5] 2.6.2 Set up time: 15 minutes Class time: About one class session Overview: The teacher will provide a basic summary of how energy we use comes from the Sun, and students will then draw energy flow diagrams using provided formulas that outline this process. Students will also write a paragraph to explain their diagrams. Objectives: Students will learn about sources and forms of energy and then make energy flow diagrams that describe how energy makes its way from the Sun into the forms that humans commonly use. Materials: Pencils Markers or colored pencils Energy Flow Diagram student worksheet Notebook paper Scissors Glue stick Background: The Sun provides warmth and light, and it drives the natural processes that occur on the earth, such as wind, plant and animal growth, and precipitation. Without the Sun, life on earth would not be possible. It can be hard to imagine when we fill up our car or snowmachine with gasoline or when we eat a moose or salmon meal to provide energy for our bodies that the Sun made that possible. The following lesson will help students understand the path that sunlight takes to eventually become electricity or other usable energy. Examples of different processes of transforming solar energy into other usable forms of energy include: Wind: Wind is created by the uneven heating of the earth s surface by the Sun. This uneven heating is due to variations in the shape and reflectivity of the earth s surface (mountains, oceans, lakes). As areas of the earth s surface are heated by sunlight, the air above becomes warm and, because it is lighter, rises. Cold air then rushes in to fill the space where the warm air once was. This movement of air makes the wind blow. Wind turbines capture this movement of the air to power
2 generators, which produce electricity for our homes and buildings. There are plenty of windy places in Alaska, and several wind farms are being built to generate electricity, such as the Fire Island wind farm near Anchorage and the Eva Creek wind farm near Healy. Photosynthesis: Sunlight is a form of electromagnetic energy. When light is absorbed by plants, the process of photosynthesis takes place in the plant cells; light energy is converted to a chemical called ATP. In turn, ATP is used to convert carbon dioxide and water into oxygen and glucose, a source of energy that helps the plant grow. Humans and animals need oxygen to breathe and plants (and other animals!) are an important source of food for both. Precipitation: As the sun heats water in oceans and lakes, some of the water on the surface evaporates. It is converted from liquid to gas, enters into the atmosphere as water vapor, and forms clouds. These clouds eventually become dense enough that gravity pulls the water back to the earth s surface in the form of rain, sleet, or snow, collectively known as precipitation. The water from rain or melted snow helps plants to grow; it also allows lakes to maintain normal water levels, and supplies the water that keeps rivers flowing. Hydroelectric ( Hydro ): Hydropower plants capture the kinetic energy in moving water to produce electricity. Precipitation that enters dams, rivers, and streams spins turbines connected to a generator and produces electricity. An example of a hydroelectric facility in Alaska is the Bradley Lake project on the Kenai Peninsula. Passive Solar: One of the simplest ways to use energy from the Sun, which does not involve electronic or mechanical devices, is passive solar design. This method uses solar radiation as a mean to passively heat homes. By collecting and storing solar energy in structures such as floors and walls, the energy can then be distributed and used as heat when it is needed. Through proper orientation, placement, and design, buildings can take advantage of the natural heat from the Sun. Coal Formation: Over time, plants decay and form peat, which becomes buried and hardened under the earth s surface. Over millions of years, the pressure and heat from the top layers compress this peat into lignite and eventually coal. Coal is then dug up from mines and burned in coal-fired power plants to produce electricity and heat. Petroleum: Millions of years ago, tiny plants, diatoms and animals in marine environments died and decayed on the ocean floor, then became covered by silt and sand. They were buried deeper and deeper under the surface until heat and pressure from the top layers helped convert this decayed matter into petroleum, which literally translates to rock oil or oil from the earth. Petroleum, or crude oil, is extracted from deep wells and brought to the surface. It is refined into many different products, including fuels such as gasoline, propane, and diesel. Companies drill for petroleum on Alaska s North Slope and send it through the pipline to Valdez. Natural Gas: Natural gas is formed in the same way as coal and petroleum, and is found in the same deposits as these two other resources. Like petroleum, it
3 is extracted from deep wells and brought to the surface through pipes. Natural gas can be burned to produce heat and electricity. Vocabulary List: atmosphere - the mass of gas that surrounds the earth, held in place by gravity; the atmosphere plays a key role in how the Sun s radiant energy is absorbed, retained, or deflected by the Earth. crude oil - a liquid fossil fuel formed from dead organisms (usually zooplankton and algae) that were buried underground under heat and pressure for millions of years. Crude oil is a mixture of different lengths of hydrocarbons (long molecular chains of carbon and hydrogen atoms) that can be separated out depending on the length of the hydrocarbons to produce many different fuels including diesel and gasoline. coal - a fossil fuel formed from dead organisms (mainly ancient plants) that were buried underground under heat and pressure for millions of years. Coal is classified depending on its properties, including how much energy it contains. evaporation - a phase change in water from a liquid into a gas caused by energy transferred to water molecules. Through evaporation, water moves from land and water masses into the atmosphere as part of the global hydrological cycle. hydropower - energy derived from the kinetic energy in falling water and converted into electricity (hydro-electric power) or another form of work (irrigation or a mechanical device such as a mill). kinetic energy - motion energy (as opposed to potential energy); kinetic energy includes radiant, thermal, motion, sound, and electrical energy. natural gas - a fossil fuel formed from dead organisms that were buried underground under heat and pressure for millions of years. It is in a gaseous state because of its low number of carbon-carbon bonds. It is comprised mostly of methane, which is a carbon atom bonded to four hydrogen atoms. peat - water saturated organic material comprised of partially decomposed plant matter which can be dried and burned as fuel. photosynthesis - the process by which plants convert energy from sunlight into chemical energy by producing energy-rich carbohydrate molecules from water and carbon dioxide. precipitation - the portion of the global hydrological cycle where water falls to the Earth as rain, sleet, snow, hail, or mist. wind - movement of air created by the uneven heating of the Earth s surface by the Sun. Wind contains kinetic energy that is derived from radiant energy provided by the Sun. Gear Up: Explain to students that energy is all around us, but it changes forms. The Sun, a massive ball of flaming gases, helps to make life on earth possible and is the
4 main source of energy for our planet. The Sun provides heat and light, and it influences natural processes and cycles on Earth. Review examples of the different processes from the background information. Activity: Explain how the Sun is a source of heat and light for our planet and how the natural processes resulting from this heat and light help humans to produce and use energy. Next, explain the different processes detailed in the Background section, perhaps writing the explanations on the board. Hand students the Energy Flow Diagram worksheet and explain that they are to illustrate the formulas with pictures (picture, arrow, next picture, etc.) and write a paragraph explaining the process on a separate sheet of notebook paper. Students could cut and paste their diagrams onto the top of the notebook paper before writing the paragraph explaining the diagram. Another option for this assignment is to assign a diagram to each group of students and have them cut pictures from magazines to create their diagram. Depending on the available resources, this activity could also be done on a computer using a drawing program. If class time is running short, have students pick 2 or 3 formulas to illustrate and explain, then assign the remaining ones as homework. Extension: Have students work in groups to present one source of energy that we use, using library and/or internet research along with their diagrams. Students should explain where the resource comes from and the various ways that we use the energy derived from this source. Students can include their own ideas for ways to use the resource more efficiently. Additional Resources: Weather Wiz Kids This website provides fun information about the fascinating world of weather for students, teachers and parents. Wind http://www.weatherwizkids.com/weather-wind.htm Precipitation http://www.weatherwizkids.com/weather-rain.htm Information on winter storms http://www.weatherwizkids.com/weather-winterstorms.htm Biology 4 Kids: Photosynthesis This website provides a basic explanation of photosynthesis. http://www.biology4kids.com/files/plants_photosynthesis.html
5 U.S. Energy Information Administration Energy Kids This website provides background information and lessons on non-renewable resources. http://205.254.135.24/kids/energy.cfm?page=nonrenewable_home-basics The Alaska Energy Wiki Contains pages on energy resources in Alaska which would be a great way for more advanced students to better understand how we capture energy from natural resources and convert it into electricity and heat. http://energy-alaska.wikidot.com/resources Alaska Grade Level Expectations addressed: Reading Performance Standards The student restates/summarizes information by: [3] 1.4.1 Retelling or dramatizing a story after reading it. [4] 2.4.1 Retelling a story in correct sequence or identifying the correct sequence of events in a story. [5] 2.4.1 Restating and summarizing main ideas or events in correct sequence after reading a text (e.g., paraphrasing, constructing a topic outline, using graphic organizers) or identifying accurate restatements and summaries of main ideas or events or generalizations of a text. The student follows written directions by: [3] 1.6.1 Completing a simple (1-2 step) task by following written directions. [3] 1.6.2 Identifying the sequence of steps in simple directions. [4] 2.6.2 Identifying the sequence of steps in multi-step directions. [5] 2.6.2 Identifying the sequence of steps in multi-step directions. Acknowledgment: This material is based upon work supported by the Department of Energy under Award Number DE-EE0000827. Disclaimer: This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.