What is the cost of inefficiency?

Time Required
2 class periods
Students will learn about work, energy and power and that using electrical appliances and devices has economic and environmental costs.


Students will learn about the concepts of work, power, and energy and how they translate to energy efficiency. Students will also read about energy efficiency and how sustainable energy use translates to cost savings. Through a demonstration of light bulb wattage using a Kill-A-Watt meter, students will be able to get a better sense of how to make small changes that lead to a bigger energy-saving impact.

Next Generation Science Standards

Disciplinary Core Ideas

  • PS2.A Forces and Motion
  • PS2.B Types of Interactions
  • PS3.A Definitions of Energy
  • PS3.B Conservation of Energy and Energy Transfer
  • PS3.C Relationship Between Energy and Forces
  • ETS1.A Defining and Delimiting an Engineering Problem

Cross Cutting Concepts

  • Cause and Effect
  • Energy and Matter
  • Patterns

Learning Objectives

At the end of the lesson students will be able to

  • Define the concepts of work, power, and energy, and provide examples of each
  • Describe the relationship between work, power, and energy
  • Know how to calculate the economic and CO2 savings from using energy-efficient appliances
  • Understand the concepts of energy efficiency and energy conservation and provide examples of each


  • 2 lamps
  • 2 light bulbs of equal brightness
  • Multimeter
  • Calculator
  • Student reading passages and student worksheets

Additonal Teaching Resources