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Sustainability Lesson Clearinghouse

Hybrid Vehicles: Cut Pollution & Save Money

Lesson Description:
Alternatives to internal combustion engines have been tried over the years, but none have outlasted or replaced the gasoline- or diesel-powered internal combustion engine. The Stanley Brothers produced steam-powered automobiles between 1902 and 1927, but even their aggressive advertising campaign could not halt the popularity of the "internal explosion engine," as they called it. Chrysler experimented with turbine-powered vehicles from 1954 to 1979, but abandoned the effort because of difficulties matching the stop-and-go requirements of an automobile with the constant-speed preference of a turbine. Presently, several automotive companies are doing research on fuel cells, which combine hydrogen or methane with oxygen to create electricity without combustion, but the technology is still a few years away from being economically feasible. Electric vehicles have been around for nearly a century, but because of limited energy-storage capacity (batteries) and the resulting limitations on range and power, they have never been popular as replacements for internal combustion engine powered vehicles. in early 2007, an entrepreneur in San Jose, California, announced the introduction of an all-electric sports car.

Rising gasoline prices and the need to cut back on emissions (or pollution) from automobile engines have caused automakers, automotive industry researchers and consumers to take another look at alternatives to the internal combustion engine.

One contemporary, popular alternative is the hybrid electric vehicle, which combines an internal combustion engine with an electric motor, a large bank of batteries, and a computer controller.

By the end of this module, students will:
  • Know the definitions of internal combustion engine, hybrid electric vehicle, emissions, and pollution.
  • Be able to calculate the percentage reduction in emissions achieved by a hybrid electric vehicle.
  • Be able to calculate the increase in fuel mileage, or the decrease in fuel consumption, for a hybrid electric vehicle.
  • Be able to calculate the payback period for purchase of a hybrid electric vehicle.
  • Understand the difference between a part-to-part ratio, a part-to-whole ratio, and a rate.
  • Bee able to set up and solve proportions using rates and ratios.
  • Bee able to set up and solve percentages as proportions.
  • Be able to describe a linear relationship in terms of rate and starting point, using a graph, a table or an equation.
  • Be able to find the y-intercept and the x-intercept of a linear relationship, using a graph, a table or an equation.

Lesson Type:
  • Other

Sustainability Topic:
  • Energy
  • Waste Reduction

Standards Addressed:
Colorado Model Content Standards for Mathematics, amended 9-15-05, Colorado Department of Education.

Standard 1
  • Students develop number sense and use numbers and number relationships in problem-solving situations and communicate the reasoning used in solving these problems.
  • Benchmarks
    • Use the relationships among fractions, decimals, and percents, include the concepts of ratio and proportion, in problem-solving situations.
    • Use number sense to estimate and justify the reasonableness of solutions to problems involving integers [and] rational numbers.

Standard 2
  • Students use algebraic methods to explore, model, and describe patterns and functions involving numbers, shapes, data, and graphs in problem-solving situations and communicate the reasoning used in solving these problems.
  • Benchmarks
    • Represent, describe, and analyze patterns and relationships using tables, graphs, verbal rules, and standard algebraic notation.
    • Describe patterns using variables, expressions, equations, and inequalities in problem-solving situations.
    • Analyze functional relationships to explain how a change in one quantity results in a change in another (for example, how the area of a circle changes as the radius increases, or how a person’s height changes over time).
    • Distinguish between linear and nonlinear functions through informal investigations.
    • Solve simple linear equations in problem-solving situations using a variety of methods (informal, formal, graphical) and a variety of tools (physical materials, calculators, computers).

Standard 5
  • Students use a variety of tools and techniques to measure, apply the results in problem-solving situations, and communicate the reasoning used in solving these problems.
  • Benchmarks
    • Estimate, use, and describe measures of distance, perimeter, area, volume, capacity, weight, mass, and angle comparison.

Standard 6
  • Students link concepts and procedures as they develop and use computational techniques, including estimation, mental arithmetic, paper-and-pencil, calculators, and computers, in problem-solving situations and communicate the reasoning used in solving these problems.
  • Benchmarks
    • Use models to explain how ratios, proportions, and percents can be used to solve real-world problems.
    • Select and use appropriate algorithms for computing with commonly used fractions and decimals, percents, and integers in problem-solving and determine whether the results are reasonable

Materials Needed:
  • The minimum information needed to complete this module can be found in this packet. additional information, which the students will need to collect, include the following: 
  • Up-to-date prices of normal gasoline-powered vehicle and a hybrid electric vehicle.
  • Up-to-date prices of gasoline and diesel fuel
  • Average monthly distance traveled by a typical family car, in miles
  • Fuel milage of a typica family car, in miles per gallon.  

School or Group:
Energy Education and Workforce Development
Contact Email:
Located in: Science

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