Earth contains a variety of plants to provide food, medicine and, most importantly, energy sources for humans. In this lesson, students will categorize plants by their components and shapes. Additionally, they will learn the mechanisms...

A video workshop looking at the world's use of fossil fuels as an energy source. Includes discussions about the limits of fossil fuel use and the importance of teaching energy conservation and investing in alternative energy sources.

Learn about the process of generating solar electricity from photovoltaic cell and concentrating solar power technologies. [3:57]

This video segment illustrates a variety of energy sources used to generate electricity, some of which are in use and some of which are under exploration. [6:09]

Cellulosic ethanol? Cyanobacteria? Algae? Microbial fuel cells? Join a discussion about current research into biofuels, and where the field is headed.

Ira talks with several researchers looking at innovative ways to harvest energy from plant materials, including gasoline-like chemicals, ethanol, and hydrogen production.

Join Ira Flatow in this hour of Science Friday for a discussion of alternative energy and biofuels.

A good argument for the use of wind power lays out both the benefits and the challenges of using this alternative energy source. [2:33]

Find out what obstacles still stand in the way of alternative energy sources. Jennifer Kurtz discusses the current state of hydrogen fuel technology.

Find out what wave energy is, and how it works. [2:17]

A new report says wind turbines have the potential to supply all the world's energy needs. Sciene Friday talks with the authors of the report about their findings, and the barriers to putting such a plan into practice.

In a state known for oil, can a city change its energy habits? San Antonio's mayor says he wants to make his city a hub for alternative and renewable energy businesses. Ira Flatow and guests discuss how a city can change its energy habits.