Hands-on Activity: Greenewables

Contributed by: Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder

Poster includes benefits, costs, statistics and technologies of biomass energy.
Poster presentation on biomass as a source of alternative energy.
Copyright © Physics 102 Class, St. Mary's College, Notre Dame, IN. Used with permission.


Students form expert engineering teams working for the (fictional) alternative energy consulting firm, Greenewables, Inc. Each team specializes in a form of renewable energy used to generate electrical power: passive solar, solar photovoltaic, wind power, low-impact hydropower, biomass, geothermal and (for more advanced students) hydrogen fuel cells. Teams produce poster presentations making a case for their technology and produce an accompanying PDF document using Adobe Acrobat that summarizes the presentation. This activity is geared towards fifth-grade and older students, and Internet research capabilities are required. Some portions of this activity may be appropriate with younger students.

Engineering Connection

Every day we use electricity to light our homes, listen to the radio, keep our food cold, etc. Engineers are concerned about how all this energy is produced and what it is doing to our environment. They are currently developing alternative energy sources and ways to conserve energy. Solar, wind and nuclear power are some of the alternatives to the existing high carbon-dioxide-emitting coal plants. However, no energy source is perfect and engineers are constantly weighing the pros and cons of each energy source.

Educational Standards

Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards.

All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standards Network (ASN), a project of D2L (www.achievementstandards.org).

In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc.

Suggest an alignment not listed above

Pre-Req Knowledge

An understanding of renewable and nonrenewable energy sources, and the concept of energy conservation. A familiarity with Internet research capabilities.

Learning Objectives

After this activity, students should be able to:

  • Use a full range of strategies to comprehend technical writing.
  • Write stories, letters and reports with greater detail and supporting material.
  • Choose vocabulary and figures of speech that communicate clearly.
  • Draft, revise, edit and proofread for a legible final copy.
  • Apply skills in analysis, synthesis, evaluation and explanation to their writing and speaking.
  • Incorporate source materials into their speaking and writing (for example, interviews, news articles, encyclopedia information).
  • Write and speak in the content areas using the technical vocabulary of the subject accurately.
  • Recognize stylistic elements such as voice, tone and style.
  • Recognize, express and defend a point of view orally in an articulate manner and in writing.
  • Apply skills in analysis, synthesis, evaluation and explanation to their writing and speaking.

Materials List

  • poster-making materials
  • computers with word processing and graphics software
  • Internet access
  • printer
  • (optional) Adobe Acrobat software for making PDF documents


Did you know that a pile of cow manure can be used to generate electricity? Or, a field of corn? Or, sewer sludge? Or, a big heap of rotting bananas? That's right. Australian engineers have developed an electricity generator fueled by decomposing bananas (see BBC News story, Bananas Could Power Aussie Homes). They plan to build a "full size, fruit-fired power station" to supply the power for as many as 500 homes. This is an example of how biomass—living material that releases methane gas as it decomposes—is used to power an electrical turbine to generate electricity.

You probably already know that high dams such as the Hoover Dam are used to capture the energy of water falling from a great height to generate electricity. This is called high-head hydropower. But did you know that electricity can be generated in a relatively shallow stream, river or tidal basin? That is called low-head hydro and it is more cost-efficient and environmentally friendly than building high dams. In this case, the motion (kinetic energy) of the water turns the electrical turbine. (For more on low-head hydro, see the literacy activity for Energy unit, Lesson 8: A Case of Innovation.)

In the literacy activity for Energy unit, Lesson 7: Windmill of Your Mind: Distributed Energy Goes to School, you learn how a windmill provides the electricity for a school, again by driving an electrical turbine.

Biomass, hydropower and windmills—These are just three sources of alternative energy for generating electricity that you will investigate in this activity. Let's learn about some new ways to cook up electricity!


biomass energy: An energy resource derived from organic matter. Examples include wood, agricultural waste and other living-cell material that can be burned to produce heat energy. Also, algae, sewage and other organic substances may be used to make energy through chemical processes. Source: U.S. Department of Energy, www.ott.doe.gov/biofuels/student_glossary.html.

carbon neutral: Emitting no net carbon dioxide into the atmosphere. Source: Wordspy, http://www.wordspy.com/words/carbonneutral.asp.

greenewables: A made-up, portmanteau word combining "green" and "renewable," suggesting types of energy that are both green and renewable. Source: Jane Evenson

head: The source, fountain, spring or beginning, as of a stream or river; as, the head of the Nile; hence, the altitude of the source, or the height of the surface, as of water, above a given place, as above an orifice at which it issues, and the pressure resulting from the height or from motion; sometimes also, the quantity in reserve; as, a mill or reservoir has a good head of water, or 10 feet head; also, that part of a gulf or bay most remote from the outlet or the sea.

kilowatt hour: A unit of energy. 1 kWh = the work done by a power of 1,000 watts operating for one hour.

nonrenewable: Of or relating to an energy source or a natural resource that is not replaceable after it has been used. Nonrenewable energy sources include oil or natural gas. A nonrenewable natural resource is metallic ore.

portmanteau: A new word formed by joining two others and combining their meanings. Examples: smog combines smoke and fog, motel combines motor and hotel, brunch combines breakfast and lunch.

renewable: Relating to or being a commodity or resource that is inexhaustible or replaceable. Renewable energy resources include solar energy and firewood.


With the Students

  1. Divide the class into teams of three or four students each.
  2. Tell the students: You are engineers fresh out of college who have just been hired by the alternative energy consulting firm, Greenewables, Inc. You work on a team that specializes in a form of renewable energy used to generate electrical power: passive solar, solar voltaics, wind power, low-impact hydropower, biomass, geothermal and (for more advanced students) hydrogen fuel cells.
  3. Tell the students: Your team will produce a poster demonstrating the benefits of the technology you specialize in and a one- or two-page accompanying summary document in PDF format using Adobe Acrobat software, which incorporates images, graphic elements and appropriate fonts. Or, use a paper template your teacher provides, with a selection of images from which you can choose to cut and paste. Make your best case that your technology will help power the future.
  4. Observing: First, conduct some background reading and research to learn as much as you can about how electricity is generated using alternative fuel sources. The best place to start is the National Renewable Energy Laboratory. Also visit the Alternative Energy Institute and the U.S. Department of Energy's Energy Efficiency and Renewable Energy websites. The TXU Energy's Generating Electricity website provides clear explanations of how electricity is generated using conventional and alternative sources of energy.
  5. Thinking: Supporters of alternative and renewable energy sources, such as the Union of Concerned Scientists, discuss the hidden environmental and social costs—such as health costs and environmental cleanup costs—of conventional fossil fuel sources of energy. These costs are not typically factored into the direct cost of the energy, which to you and your family represents the cost of electricity per kWh.
  6. Renewable energy sources have difficulty competing in the marketplace with conventional sources because they have a higher direct cost to the consumer per kWh. Environmental skeptics challenge supporters of renewable energy sources by saying that the costs of these sources, in terms of maintenance and the inefficiency of operating small plants (called economies of scale) ensure that renewable sources will not be able to compete with conventional, at least not in a timely enough manner to have any impact on global warming or other environmental problems. What do you think? Remember, you are the expert on your Greenewable technology!
  7. Writing: Make your written summary closely parallel your poster presentation, which itself is a summary of your argument for the benefits of your Greenewable technology. Here are a few of the questions to answer:
    • What is the energy source and how is it used to generate electricity?
    • What are the requirements and limitations of the source in terms of availability: Proximity to a geothermal source or river, stream or tidal basin? Reliable wind that is strong enough to turn a turbine, but not too strong to damage it? Unobstructed exposure to the sun's rays? Etc.
    • What environmental impacts are involved in exploiting the source (impact on fish and other wildlife, for example) and what are the "hidden costs" of minimizing any potential damage?
    • What are the pros and cons of the source?
    • How much will electricity cost if it is produced by this source? Can it compete in the marketplace?
    • Will the source generate enough power reliably to make the local plant able to sell energy back to the grid?
    • How does this source compare with others in terms of potential to "power the future"?

Troubleshooting Tips

To get to online news articles in the References section conduct a keyword search on one of these search terms or a combination of the two through any search engine available on the internet: "global warming," "white house report" or "new way to generate electricity."


Pre-Activity Assessment

Call-Out Questions/Quiz: Use call-out questions and a vocabulary quiz to reinforce basic concepts and vocabulary introduced during the Observing session.

Activity Embedded Assessment

Call-Out Questions: Use call-out questions during the Thinking discussion to test students' understanding of the concepts.

Post-Activity Assessment

Posters/Reports: Review the students' poster presentation and summary document to gauge their understanding of the concepts.

Activity Extensions

Greening the red planet? For an interesting spin on the theme of this activity, have students build their poster presentations around energy sources that would be suitable on Mars. Would green considerations still be relevant on the red planet? For some ideas, visit the Mars Millennium Project online. (search via any online search engine).

Go CarbonNeutral: Investigate organizations that provide ways to balance CO2 (carbon dioxide) emissions in the atmosphere to slow down global warming. Learn what you and your family can do to neutralize the carbon contribution you make to global warming. Search the Internet for relevent websites.

How crazy can you get? Electricity from manure, germs... bananas? Go on a hunt for the wildest sources of alternative energy you can find. Do a keyword search (try "new way to generate electricity" for starters) at http://www.google.com.

Have you heard of a bus powered by used vegetable oil from a cafeteria? Research and report on this alternative fuel.

Activity Scaling

Choose teams to reflect an equitable distribution of skills and range of talents appropriate to the tasks.

Additional Multimedia Support

Bananas Could Power Aussie Homes. August 27, 2004. BBC News, UK Edition. Accessed 2005. http://www.rense.com/general56/aasu.htm


Alternative Energy Institute. The Alternative Energy Institute.

Clean Energy Basics: Student and Teacher, "As a student or teacher, what do I need to know about energy efficiency and renewable energy?" National Renewable Energy Laboratory (NREL), U.S. Department of Energy. Accessed 2005.

Clean Energy: The Hidden Cost of Fossil Fuels. Updated August 10, 2005. Union of Concerned Scientists. Accessed 2005. http://www.ucsusa.org/clean-energy/coal-and-other-fossil-fuels/hidden-cost-of-fossils#.WIEWj1MrKM8

Colorado Wind & Distributed Energy: Renewables for Rural Prosperity. April 13-24, 2004. Governor's Office of Energy Management and Conservation, CO. Accessed 2005. http://www.businesswire.com/news/home/20040127005671/en/Colorado-Wind-Distributed-Energy-Renewables-Rural-Prosperity

Cook, Gareth. New Fuel Cell Uses Germs to Generate Electricity. Published September 8, 2003. The Boston Globe. Accessed 2005. http://archive.boston.com/news/local/articles/2003/09/08/new_fuel_cell_uses_germs_to_generate_electricity/

Energy Education & Training. Updated June 2, 2005. Energy Efficiency and Renewable Energy, U.S. Department of Energy. Accessed 2005.

Energy Efficiency and Renewable Energy. Updated September 19, 2005. Energy Information Portal, U.S. Department of Energy. Accessed 2005. 

Energy Information Administration. Updated September 20, 2005. U.S. Department of Energy. Accessed 2005.

Energy Kid's Page. Energy Information Administration, U.S. Department of Energy. Accessed 2005. http://www.eia.gov/kids/

Europe's Leading Eco-Centre. Centre for Alternative Technology. Accessed 2005. http://www.cat.org.uk

Generating Electricity, Educational Programs. TXU Energy, Dallas, TX. Accessed 2005.

Mars Millennium Project: A national arts, sciences, technology education initiative. Accessed 2005. http://mmp.planetary.org/

McKee, Maggie. "White House Report Says People Cause Global Warming." Published August 27, 2004. Breaking News, New Scientist, Reed Business Information Ltd. Accessed 2005. https://www.newscientist.com/article/dn6334-white-house-report-says-people-cause-global-warming/

National Renewable Energy Laboratory (NREL). Updated September 16, 2005. U.S. Department of Energy. Accessed 2005. http://www.nrel.gov/

Our Changing Planet, the U.S. Climate Change Science Program for Fiscal Years 2004 and 2005. Updated August 25, 2004. U.S. Climate Change Science Program, U.S. Global Change Research Program, Washington, DC. Accessed 2005. http://www.globalchange.gov/browse/reports/our-changing-planet-us-climate-change-science-program-fiscal-years-2004-and-2005

R.E.A.C.T. Renewable Energy Activities – Choices for Tomorrow, Teacher's Activity Guide for Middle Level Grades 6-8. National Renewable Energy Laboratory (NREL), U.S. Department of Energy, Golden, CO. Accessed 2005. http://www.nrel.gov/docs/gen/fy01/30927.pdf

Saint Mary's College Year 2100 Energy Project. Introduction to Physics II, Saint Mary's College, Notre Dame, IN. Accessed 2005.


Jane Evenson; Malinda Schaefer Zarske; Denise W. Carlson


© 2005 by Regents of the University of Colorado

Supporting Program

Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder


The contents of this digital library curriculum were developed under grants from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation (GK-12 grant no. 0338326). However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.

Last modified: January 19, 2017