In this program, we introduce students to the concept of efficiency, which is a measure of how much useful energy you get out of something compared to the amount of energy that you put into it. We answer a bunch of questions including: How much light energy do we get out of light globes compared to the amount of electrical energy that goes into them? Hint: it’s not much; they should be called heat globes! How much kinetic energy do we get out of cars compared to the amount of chemical energy that we put into them? Hint: it’s a bit more, but not that much more! And how do our arched feet make us the long-distance running champions of the animal world? This video is the most energy-efficient way of learning everything that you need to know about energy efficiency!

Originally released by Liacos Educational Media, 2018. Streaming video file encoded with permission for digital streaming by Infobase on March 22, 2018.

Part A: Introduction (2:24); --Part B: Power (in Watts) (5:21); -- Part C: Improving Efficiency (6:15); -- Part D: Heat Wastage and Energy "Loss" (9:09); -- Part E: Efficiency in Nature and Industry (6:34); -- Credits: Shedding Light on Energy: Episode 3—Energy Efficiency (0:37);.