This introductory video describes the basic principles of residential geothermal heat pumps.

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 animation illustrates how heat energy from deep in Earth can be utilized to generate electricity at a large scale.

This is a series of 10 short videos, hosted by the National Science Foundation, each featuring scientists, research, and green technologies. The overall goal of this series is to encourage people to ask questions and look beyond fossil fuels for innovative solutions to our ever-growing energy needs.

This video segment explores whether, in principle, renewable energy resources could meet today's global energy needs of about 15.7 terawatts.

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.

This Flash animation describes how hybrid-electric vehicles (HEVs) combine the benefits of gasoline engines and electric motors and can be configured to obtain different objectives, such as improved fuel economy, increased power, or additional auxiliary power for electronic devices and power tools.

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 interactive, students can investigate a typical hydrogen fuel cell prototype car from its fuel cell stacks to its ultracapacitor, a kind of supplementary power source.

The limited-production vehicle seen in this feature is a Honda 2005 FCX, which is typical of the kinds of hydrogen fuel cell cars that some major automakers are researching and developing.

In this activity, students use Google Earth to investigate a variety of renewable energy sources and select sites within the United States that would be appropriate for projects based on those sources.