National Science Standards

Science as Inquiry: Content Standard A:
All students should develop:

Abilities to do scientific inquiry

Physical Science: Content Standard B:
All students should develop an understanding of:

Conservation of energy and increase in disorder
Interactions of energy and matter

Life Science: Content Strand C:
All students should develop an understanding of:

Matter, energy, and organization in living systems

Earth and Space Science: Content Strand D:
All students should develop an understanding of:

Energy in the earth system

Science and Technology: Content Standard E:
All students should develop:

Abilities of technological design
Understanding about science and technology

Science in Personal and Social Perspectives: Content Standard F:
All students should develop understanding of:

Environmental quality

Learning Objectives

Each student will:

Describe the components of an HVAC system.

Determine which factors that influence the efficiency of an HVAC system have the greatest impact.

Make and test hypotheses about HVAC systems and cost effectiveness.

Make and test hypotheses about HVAC systems and energy efficiency.

Background Information, Vocabulary and Materials

Background Information

Modern air conditioning has only been widely available since after World War II. Short histories of air conditioning are available through web sites such as the Air Conditioning and Refrigeration Institute and About sites, at:

You can use these or other sites as homework reading before this lesson to help students understand HVAC systems.

Back in lessons 2 and 3, we introduced the concept of the building envelope system and briefly noted that the HVAC system is used to “deal with what’s left”, to make a building comfortable and productive after the envelope systems get us part of the way there.

In this lesson we want to provide additional information about how typical HVAC systems work, and then discuss several factors that help determine how efficiently an HVAC does its job. We will do this using the HVAC.ppt PowerPoint presentation. Familiarize yourself with the presentation, and be sure to read the notes given for each slide (available as you review the presentation in slide or outline view) that will help you understand and explain the concepts to the class.

Note here that lighting is also important in achieving comfortable and productive spaces. However, since we will be concentrating on lighting by using the Lighting in the Library audit in lessons 6-9, we won't focus on it now.

There is also an optional exercise designed to pull all the material from Lessons 1-4 together by benchmarking how well your school is doing on energy consumption compared to other schools. See the Student Activity section of this lesson for more details on this comparison and the link to the benchmarking web site.

Finally, we will use EnergyGauge^&reg again to see how much an efficient HVAC system can reduce energy use costs compared with the Base Home and Efficient Envelope Home. See the Student Activity section for details.

Vocabulary

SEER

HSPF

COP

Duct Leakage

plenum

Materials

HVAC.ppt presentation (3.9M PowerPoint)
EnergyGauge^® Student Edition software

Lesson Procedures

Presenting the Information

This lesson refers to Advance Organizer slide number five. Discuss homework on the history of air conditioning if assigned.

Review how the HVAC system is used to “deal with what’s left” to make a building comfortable and productive after the envelope systems get us part of the way by reducing heat transfer and infiltration. Refer back to the Advance Organizer and note that this is the second part "Improving the Solution." First we improve the envelope, now we'll look at adding efficient HVAC systems.

In this lesson we want to provide basic information about how typical HVAC systems work, and then discuss several factors that help determine how efficiently an HVAC system does its job.

Use HVAC.ppt presentation to show students how residential air conditioners and heating systems work and introduce HVAC efficiency. Make sure to have reviewed the notes that accompany the presentation (notes are viewed within the presentation in slide or outline view) first to help you explain the slides to your students.

Student Practice/Activity

Run the EnergyGauge USA^® Base Home and Efficient Envelope Home for your climate again to review energy costs, and then run the Efficient Envelope and HVAC Home. Discuss your results. How much do you save by improving the HVAC system? What if electricity costs were 10% or 33% higher than they are now? Do you think such increases could occur within the next 5 years? You can experiment with changing the HVAC systems and system efficiencies and see how the changes affect energy costs.

[Optional: Run the EnergyGauge warm climate Efficient Envelope and HVAC home and the cold climate Efficient Envelope and HVAC home each in both Miami Florida and in Minneapolis Minnesota. To change the climates, change the Design State and Design Location on the Climate screen. Do the results surprise you? The point here is that an efficient house up North will be different than an efficient house in the South! The difference is mainly due to the fact that in cold climates we're mostly concerned with winter temperature differences (between indoors and outdoors), while in warm climates we're mainly concerned with summertime heat gain from the sun.]

[Optional: “Benchmark Your Building” activity using Oak Ridge National Laboratory’s benchmarking tool to compare the energy use of your school with other schools. Go to: http://eber.ed.ornl.gov/benchmark/intro.htm. After completing the on-line activity, discuss how your school compares with other schools.]

Feedback

Take several minutes to review HVAC systems and answer any questions.

Handouts and Worksheets

None

Critierion-Referenced Test

This material part of final test. See Testing Blueprint in Teacher's Guide for details.

Individual pages from this web site may be printed and duplicated for
student classroom use provided that proper credit is given to
the Florida Solar Energy Center (FSEC).