This video is one of a series produced by the Switch Energy project. It highlights the use of biofuels as a renewable source of energy.

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

This Energy Flow Charts website is a set of energy Sankey diagrams or flow charts for 136 countries constructed from data maintained by the International Energy Agency (IEA) and reflects the energy use patterns for 2007.

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

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 interactive diagram from the National Academy of Sciences shows how we rely on a variety of primary energy sources (solar, nuclear, hydro, wind, geothermal, natural gas, coal, biomass, oil) to supply energy to four end-use sectors (residential, commercial, industrial, and transportation). It also focuses on lost or degraded energy.

This is a hands-on inquiry activity using zip-lock plastic bags that allows students to observe the process of fermentation and the challenge of producing ethanol from cellulosic sources. Students are asked to predict outcomes and check their observations with their predictions. Teachers can easily adapt to materials and specific classroom issues.

This short video touches briefly on the future of global energy and which energy sources best meet four energy-choice criteria: affordable, available, reliable, and clean.

This video stitches together nine separate videos about energy sources (hydro, coal, geothermal, nuclear, wind, biofuels, solar, natural gas, and oil) from the Switch Energy site. Videos can be viewed as a group, or separately, each under their own title.