This video discusses how methane digesters turn waste from dairy cows, food garbage, and other organic matter into usable gases and other fuels.

This short video reviews how nations and individuals can work together to reduce the emission of CO2. It discusses strategies to reduce greenhouse gas emissions (energy conservation, renewable energies, change in energy use) and the role that government can play in this process.

This suite of short video clips is part of a series produced by the Switch Energy project. There are several video segments that discuss different perspectives of biofuels as a renewable source of energy.

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

This animated slideshow introduces biodiesel as a fuel alternative. With concern about the use of petroleum-based fuels at an all-time high, biodiesel is experiencing a popularity surge. And algaeâotherwise known to some as pond scumâ are grabbing headlines as the next potential biodiesel superstar. But how and why do algae make oil? And why do they make so much of it? In this audio slide show, U.C. Berkeley's Kris Niyogi describes the process and its potential.

In this activity, students explore the basic living requirements of algae (phytoplankton)through hands-on experience and an interactive game. Students investigate what algal biofuels are, how they are made, where they can grow, and, most importantly, why this topic should be investigated. Algal biofuels are an emerging source of renewable energy.

This is a team-based activity that teaches students about the scale of the greenhouse gas problem and the technologies that already exist which can dramatically reduce carbon emissions. Students select carbon-cutting strategies to construct a carbon mitigation profile, filling in the wedges of a climate stabilization triangle.

In this activity, students explore real data about renewable energy potential in their state using a mapping tool developed by NREL (National Renewable Energy Laboratory) to investigate the best locations for wind energy, solar energy, hydropower, geothermal energy, and biomass.

This video describes how geothermal heat resources in California have been tapped to supply 850 MW of electricity. Images and animations show how the area known as The Geysers has been developed to capture steam, produced from trapped rainwater and heated by the earth. Major challenges include finding suitable geothermal resources to develop, and ensuring that underground water is replenished.

This hands-on activity introduces students to the process of fermenting different carbohydrate sources into ethanol. Teachers demonstrate yeasts' inability to metabolize certain food sources.