Lesson Plan: Energy Conservation
Concepts
1. Energy conservation can be defined as the protection, preservation,
management, or restoration of our energy resources.
2. Conservation is one of the ways we can reduce energy use, thus reducing
the amount of pollutants put into our atmosphere from the burning of fossil
fuels and reducing the negative effects felt from the burning of these fuels.
3. Conservation methods include modifications to our daily behaviors and
choosing energy conscious products.
Key Questions
1. What appliances use the most energy in the average home?
2. What are some ways you can conserve energy in your home?
3. What are some examples of energy conscious products?
Student Learning Objectives
The student will be able to calculate energy use and
analyze how changing their behaviors and appliances
will affect the energy their use.
The student will be able to conduct an experiment and
make comparisons based on experimental evidence.
Standards
National
Sci: A1d, A1e,
A1h, A2c, F5a;
Math: IB2, VB,
IXC;
Tech: 16
Sci: A1c, A1d,
A1e, A1g, A1h,
A2c;
Math: IVB3, IVC1,
VB, IXC
Anticipatory Set
o We use energy in our lives everyday. The energy we use comes
primarily from burning fossil fuels. We use some of that energy in the
form of heat, for example natural gas and oil to heat our homes, and
some of the energy we use is in the form of electricity. In the US,
electricity accounts for about 40 percent of our total energy use
(www.eia.doe.gov). About half of that electricity is generated by
burning coal.
o In our homes, electricity accounts for about 15% of the total energy we
use (see reference tables and chart at end of lesson plan for more
details). Our homes are filled with appliances that use electricity to
work for us. Toasters, microwave ovens, televisions, and computers
are some examples of the electrical appliances we use everyday.
NYS
7
7
o We compare electrical power use in units called watts. A watt is a
measure of the rate of energy use (energy ÷ time). The total energy
these appliances use over a given period of time is measured in Watthours, or more commonly, kilowatt-hours (kW-h), equal to the watts x
the time the appliance is used.
o Looking at the electrical consumption of different appliances helps us
determine which ones use large amounts of electricity and which do
not. Knowing this information helps us to make better energy-saving
choices, either by using appliances less often or by changing out older,
higher energy consumers for newer, more energy efficient models.
o Some of the largest electricity consumers include central air
conditioning, electric water heaters, refrigerators and freezers. Older
models use much more electricity than newer, energy-star models –
the energy savings offset replacement costs when buying new
products.
o Students can develop better energy saving habits if they are aware of
how much energy their “bad habits” cost.
o Many new appliances and equipment “leak” electricity, even when they
are turned off. The average U.S. household spends about $40
annually for electricity leaked by appliances in standby mode.
o Lighting accounts for 20-25% of all the electricity used in the United
States. An average household uses 5-10% of its electricity for lighting.
A commercial industry on the other hand consumes 20-30% of their
electricity in lighting only. Fifty percent or more of the energy used for
lighting is wasted by obsolete equipment, inadequate maintenance, or
inefficient use.
o Energy savings for lighting, as for all appliances, will require either
reduction in use or more efficient usage.
Key Terms
Conservation
Energy Audit
Incandescent bulb
Leaking Electricity
Life cycle analysis
Light emitting diode (LED)
Compact Fluorescent
Lightbulb (CFL)
Watt
Energy Audit
Teaching Plan:
Day 1:
•
Some background
o Most of the energy used in the U.S. comes from burning fossil
fuels. About 1/5 (20%) of all the energy used in the U.S. is used
in our homes, and of that energy, about 15 percent is in the form
of electricity. In the U.S., about half of our electricity is
generated by burning coal (in New York State much of our
electricity comes from large hydropower plants).
o We can reduce our consumption of fossil fuels by making
different choices about the appliances and equipment we use in
our homes. In order to make effective choices, we need to
know how much electricity is used by the different appliances
found in our households.
o Different appliances in our houses use different amounts of
electricity. The biggest electricity consumers are often
equipment that operates automatically, like air conditioners,
water heaters, refrigerators and freezers. Sometimes buying
newer, energy efficient equipment is our only option for saving
energy used by these appliances, and often the energy saved
offsets the cost of the new appliance.
•
Introduce the Home Energy Audit Activity
(note there are 2 approaches to do this activity –students can audit their
actual household or school room, or they can use pictures of a model
home to find appliances for the audit. Model home pictures are provided,
or students can see www.energystar.gov for appliances in a model house)
o In this activity, we will do an energy audit of a house. An energy
audit is, according to the dictionary.com website, an evaluation
of energy consumption, as in a home or business, to determine
ways in which energy can be conserved.” We will look at some
electrical appliances and determine the amount of energy they
use. This will help us discover which appliances use large
amounts of electricity and which ones do not. We will look at
appliances that we have control over, like lighting, TV, toaster,
washing machine, as opposed to things we don’t have control
over like refrigerators and water heaters.
o You will choose one area of your house to focus your audit – for
example, the kitchen, the laundry room, the bathroom, your
computer, stereo and tv system, your lighting, and so on.
o Everyone will bring in the results from their audits, and we will
compare the electricity used by different appliances.
o This will help you determine what kind of home electric energy
savings are possible, and where you can make most effective
choices for saving electricity in your homes.
•
Complete Home Energy Audit Activity (begin the activity in class with
an example. Students may finish the rest as homework)
o Have the students read the activity instructions in (Activity:
Home Energy Audit).
o If students are using the model home, distribute pictures and
have students choose one room to audit.
o If computer access is available, students using the model home
approach can access a different model home at
www.energystar.gov, see “launch energystar@home”), which is
an interactive program that also contains options and tips for
saving energy within the home.
o Discuss the instructions and make sure everyone understands
what to do. Have the students break into small groups and do
one of the examples provided. Go through each step of the
instructions with the students to make sure they understand
what to do for each row.
o When going over the steps of the example, carefully explain the
difference between Watts, which is the power used by the
appliance (rate of energy use), recorded in row 2, and Watthours, row 9 (or kilowatt-hours kW-h, row 12), which is the total
energy used by the appliance. It is important for students to
understand that when we pay our electric bill, we pay for the
energy we use, in kW-hrs. Thus, to save on our electric bill, we
can use appliances that have lower Watt ratings, or we can use
our high-wattage appliances for shorter amounts of time.
o Have the students decide which appliances they will focus their
audit on, making sure that there is a variety done by the class.
Students may finish the activity for homework.
•
(next day, or after students have done the audit) Discuss the Activity
o Share the results of the students’ audits – make a chart on the
board, for example.
o Compare the different electricity/energy uses of the different
appliances.
o For comparison purposes, add the energy use of large
appliances such as refrigerator, water heater, air conditioner,
from the resource tables.
o What did you learn about energy conservation from this activity?
o Are there places in the house where there seems to be more
energy lost than effectively used?
o If you could make one change to save electricity in your house,
what would it be?
o Is leaking electricity important in your overall energy
consumption? What could be done to reduce the leaky
electricity?
Days 2-3:
•
Review the concept of conservation and efficiency. Tell the students
that today, they will be looking at one specific way to conserve energy
– by using more efficient types of light bulbs. (2min)
•
Light and Heat Bulb Activity (30-35 min)
o Break the students into groups of 3-4
o Hand out the activity sheets and go over the procedure (5 min)
o You will provide the lux reading for each bulb
o For Part II it is better to work as a class or in very small groups
(1-2 students)
o At the end of the Activity introduce LED (light emitting diode)
bulbs
- They emit almost no heat
- Use only 1 W for the same brightness as a 40W
Incandescent
- The bulb we have (40 W equiv) cost between $60 and $70
at the time of this printing, but this price is going steadily
down as the technology develops.
o Discuss what the students found. Emphasize that an efficient
light bulb makes light and an inefficient lightbulb also makes a
lot of heat. The heat energy is essentially wasted energy – an
energy conversion that we generally do not capture for our use.
o Go over conservation ideas (perhaps on the board) and spend a
minute or two talking about the final project. Tell the class that
they will need to start developing ideas.
o Also tell the class that they will be moving into the discussion of
alternative energy sources. Have students think about what
they know about both conventional and alternative energy
sources before the next class.
*For the Light and Heat Bulbs you have two options of how to run
things.*
•
Option 1:
o Part 1 of the activity on Day 2
o Home Light Bulb lifecycle cost analysis as homework
o Discuss Part II of the activity on Day 3
•
Option 2:
o Part 1 of the activity on Day 2, and the Incandescent Bulb
Calculations of Part II
- Students take the starting temperatures and turn on the
bulbs
- While the bulbs are heating up, complete the Incandescent
Bulb Calculations on the board as a class
- When the bulbs have heated up the students return to their
set-ups and finish up Part I.
- If there is time, discuss Part I as a class
o Assign the CFL calculations of Part II for homework
o Go over the homework on the following day.
Resources
Resource Tables 1 and 2 (attached)
For more information on household electricity consumption, see
http://www.eia.doe.gov/emeu/reps/enduse/er01_us_figs.html#1
Home Energy Audit Activity, with resource tables
www.energystar.gov, see “launch energystar@home”
Light vs. Heat Bulbs Activity
Light Bulbs Homework
Lesson Assessment
Light Bulb Homework or activity sheet completed in class
Resource Table 1: Energy Consumption, by Source, in the
Average U.S. Household (2001)
Natural
Gas
Fuel Oil
LPG
Kerosene
Million BTU
per
household
Million BTU
per
household
Million BTU
per
household
Million BTU
per
household
Electricity
Energy Consumption
in the Average U.S.
Household, 2001
Million BTU
per
household
Million
kW-hr per
household
Total Consumption, all uses
35.4
10,656
72.4
81.7
40.2
16.1
Space Heating
9
2,637
54.9
68.1
42.8
16.2
Air Conditioning
7.7
2,263
-
-
Water Heating
8.5
2,505
19.7
27.9
15.8
-
Appliances (including
refrigerator and lighting)
23.5
6,894
8.7
-
8.3
-
-
Source:
http://www.eia.doe.gov/emeu/recs/byfuels/2001/byfuels_2001.html#Electricity%20Consumption
Resource Table 2: Average U.S. Household Electric
Consumption for Major Electrical Appliances, along with
some Energystar™ Comparisons
Annual kWh Consumption
per Household
Central Air Conditioning
2,667
Room Air Conditioning
738
Water Heater
2,671
Refrigerator (see side bar)
Standard
500 (new) – 1800 (old)
Energystar™
400
Freezer
1,204
Range / Oven
458
Dishwasher
299
Water Bed Heater
960
Clothes Washer
Standard
99
Energystar™
52
Clothes Dryer
Standard
500
Energystar™
400
Appliance
The energy efficiency of
refrigerators and freezers has
improved dramatically over the
past three decades. A typical
new refrigerator with automatic
defrost and a top-mounted
freezer uses less than 500 kWh
per year, whereas a typical model
sold in 1973 used over 1,800
kWh per year. As of January 1,
2004, full-size refrigerators that
exceed the federal standard by
15% or more (and full-size
freezers that exceed it by 10%)
qualify for the ENERGY STAR
label. Compact refrigerators and
freezers must exceed the
standard by 20% to qualify for
ENERGY STAR. Source:
http://www.aceee.org/consumergu
ide/food.htm
Sources: Lawrence Berkeley National Laboratory. "Standby Consumption Values for Residential
Appliances," table. Internet. Leaking Electricity Home Page: eetd.lbl.gov/leaking. 1998., and
www.eere.energy.gov
Source: http://www.eia.doe.gov/emeu/reps/enduse/er01_us_figs.html#1