This video is one of a series of videos from the Switch Energy project. It describes three types of geothermal sources -- rare ones in which high temperatures are naturally concentrated near the surface, deep wells that require fracturing the rock and then circulating water to bring heat to the surface, and low temperature sources that use constant temperatures just below the surface to heat or cool a building. The latter two are more widely available but cost-prohibitive today.

This carbon calculator, developed by the EPA, guides students in calculating their carbon footprint and then using that information to make decisions about how to reduce their carbon emissions.

This fuel cell animation demonstrates how a fuel cell uses hydrogen to produce electricity, with only water and heat as byproducts. The animation consists of four parts - an introduction, fuel cell components, chemical process, and fuel cell stack.

In this activity, students conduct a life cycle assessment of energy used and produced in ethanol production, and a life cycle assessment of carbon dioxide used and produced in ethanol production.

This video reviews the benefits and drawbacks associated with growing corn to make ethanol.

This short video shows how humanity uses energy today; what sources we use; and why, in the future, a growing global population will require more energy.

This video is from the Energy 101 video series. It explains the process for converting micro-algae into fuel and makes the case that algae-based biofuels hold enormous potential for helping reduce our dependence on imported oil.

In this video clip from Earth: The Operators' Manual, host Richard Alley discusses China's efforts to develop clean energy technologies and to reduce CO2 in the atmosphere, by building coal plants using CO2 sequestration technology. (scroll down page for video)

Sankey (or Spaghetti) diagrams parse out the energy flow by state, based on 2008 data from the Dept. of Energy. These diagrams can help bring a local perspective to energy consumption. The estimates include rejected or lost energy but don't necessarily include losses at the ultimate user end that are due to lack of insulation.

This activity leads students through a sequence of learning steps that highlight the embedded energy that is necessary to produce various types of food. Students start by thinking through the components of a basic meal and are later asked to review the necessary energy to produce different types of protein.

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