courtesy, MÉTA

goal: raising awareness about the (voluntary and involuntary) electricity households’ wastage and their implications in terms of carbon dioxide emissions; stimulating energy saving consumption habits.

risk: energy is very often perceived as a global and quite complex issue, where individual responsibility counts very little. You should make students aware that it’s not energy use, but abuse (wastage) to provoke major environmental and health problems: energy saving is a big issue that calls for both individual and global solutions.

YXC level: 2nd level (first community), 3rd level (community at large)

YXC materials: looking ahead [BAREFOOT COLLEGE | Soweto's House | Choose Positive Energy | Climate Neutral Network] - awakening your soul [IS HARRY POTTER GREEN?] - looking for a place [Bedzed | Green House Kit | Eco-Logic Design] - social belonging [Midrand-Ecocity] - facts & figures, GENERAL DATA [Eco-Footprint] - facts & figures, ENVIROMENT [energy/Global Consumption | Energy Facts & Tips | Global Warming | renewables/INTRO | Geothermal | Solar | Biomass | Hydropower | Wind] - department store [20,000 Hours Bulb | Artificial-‘Natural’ Light | Carbon Calculator | Ecofan | Fluorescent Tubes | Solar Panel Minikit |Solar Web Provider | Tubular Skylights] - job opportunities [Development Alternatives | Ecovillages | Fabio Rosa] - trainer’s room [welcome/Classwork Sample | Burn It Up] - test & play [A Changing Climate | Global Warming? ] - links [environment/Energy | housing/Interior Design | empowered consumers/Eco & Ethical Labels]

subject areas: Science & technology | Economics & biz | Health & well-being | Social studies | Workshops

work planning: Phase 1, testing students knowledge of the issue; Phase 2, intro to the issue; Phase 3, individual homework; Phase 4, team work; Phase 5, monitoring & reporting.

testing student knowledge (with key questions): these questions should be discussed in the form of class brainstorming before any subsequent introduction to the topic.


bullet What’s the relation between energy consumption and global warming? bullet Do you know the difference between renewable and not renewable energy sources? bullet Please, enlist all types of renewable energy sources that you know… bullet What do you need electricity for? bullet In the area you live in, which kind of energy sources are the most used to produce electricity? Please, order by importance: a) fossil fuels, b) nuclear, c) renewables (please, enlist: biomass, solar, wind, etc.). bullet Broadly, do you know in which percentage each? bullet Which is the best way to address energy needs? a) reducing consumption (changing lifestyles), b) increasing renewable sources, c) increasing energy efficiency, d) all the above.


bullet In your opinion, energy is well managed or wasted in your neighbourhood? bullet At your home, which items consume the greatest amount of energy? bullet How could you reduce your electricity bill? Please, complete and order by importance: a) switching off lights and appliances when not in use, b) avoiding any wasteful use of the heating/cooling system, c) optimising appliances’ use (low temperature, full charge, etc.), d) avoiding water wastage, e) increasing home energy efficiency (through sustainable building design, energy saving appliances, light bulbs, etc.), f) other measures? bullet Could energy saving play an important role in your country’s economic future?

intro to the topic (background): it's hard to imagine life without electricity. In our homes, we rely on it to power our lights, appliances, and electronics. Many of us also use electricity to provide our homes with hot water, heat, and air conditioning. But as we use more electricity in our homes, our electric bills rise and our planet becomes more and more sick. Most electricity in fact comes from coal, nuclear, or other fossil fuel power plants. These plants contribute to a variety of environmental and social problems, including air emissions, water consumption, solid waste and noise. In turn, they can affect the environment by altering the global climate, threatening biodiversity, producing toxic waste, and causing human health risks such as cancer and respiratory disease. Moreover, the continued reliance on and depletion of fossil-fuel resources threatens our energy security.

For these reasons, energy saving is a big issue that calls for both individual and global solutions. There are many things that we can do every day to cut down on the energy we consume in the household. Moreover, apart from the environmental benefits, saving energy can also save money...

did you know?

  • In the USA, about 35% of all electricity is used to run homes;
  • in Europe, in 2001, housing accounted for 26.2% of the total EU15 energy consumption (compared to 27.7% for industrial use). Taking into account the energy needed to produce building materials, that amount exceeds 40% of total energy consumption;
  • for every kilowatt of electricity you use, one and a half pounds of carbon dioxide are released into the atmosphere*;
  • the sunlight coming through a standard-sized window can supply the same amount of light as thirty 100-watt bulbs*.

A home energy audit is the first step to assess how much energy your home consumes, and to evaluate what measures you can take to make your home more energy-efficient. You can easily conduct a home energy audit yourself. With a simple but diligent walk-through, you can spot many problems in any type of house. When auditing your home, keep a checklist of areas you have inspected and problems you found. This list will help you prioritise your energy efficiency upgrades.

1) Insulation and Air Sealing - You can reduce your home's heating and cooling costs through proper insulation and air sealing techniques. Any air sealing efforts will complement your insulation efforts, and vice versa. Proper moisture control and ventilation strategies will improve the effectiveness of air sealing and insulation, and vice versa. A proper balance between all of these elements will also result in a more comfortable, healthier home environment.
  • Locating Air Leaks - First, make a list of obvious air leaks (drafts). The potential energy savings from reducing drafts in a home may range from 5 to 30% per year, and the home is generally much more comfortable afterward. Check for indoor air leaks, such as gaps along the baseboard or edge of the flooring and at junctures of the walls and ceiling. Also look for gaps around pipes and wires, electrical outlets, foundation seals, and mail slots. Check to see if the caulking and weather stripping are applied properly, leaving no gaps or cracks, and are in good condition. Inspect windows and doors for air leaks. On the outside of your house, inspect all areas where two different building materials meet. Check the exterior caulking around doors and windows, and see whether exterior storm doors and primary doors seal tightly.

  • Insulation - Heat loss through the ceiling and walls in your home could be very large if the insulation levels are less than the recommended minimum. In the attic, determine whether openings for items such as pipes, ductwork, and chimneys are sealed. Make sure that the attic vents are not blocked by insulation. Checking a wall's insulation level is more difficult. Only a thermo-graphic inspection can do it properly. If your basement is unheated, determine whether there is insulation under the living area flooring.

2) Heating/Cooling Equipment - Heating and cooling account for about 56% of the energy use in a typical US home, making it the largest energy expense for most homes. Many heating and cooling systems have certain supporting equipment in common, such as thermostats and ducts, which provide opportunities for saving energy. Inspect heating and cooling equipment annually, or as recommended by the manufacturer. If the unit is more than 15 years old, you should consider replacing your system with one of the newer, energy-efficient units. A new unit would greatly reduce your energy consumption, especially if the existing equipment is in poor condition.

3) Lighting - Artificial lighting consumes almost 15% of a household's electricity use. Examine the wattage size of the light bulbs in your house. You may have 100-watt (or larger) bulbs where 60 or 75 watts would do. Incandescent lights (or bulbs) should be turned off whenever they are not needed. Nearly all types of incandescent light bulbs are fairly inexpensive to produce and are relatively inefficient. Only about 10%–15% of the electricity that incandescent lights consume results in light - the rest is turned into heat. Turning the light(s) off will keep a room cooler, an extra benefit in the summer. For energy savings of 60%–75%, many incandescent lamps can be replaced by compact fluorescent lamps (CFLs). A standard 18-watt CFL replaces a 75-watt A-type lamp. CFLs are especially economical in spaces where lights are needed for longer periods of time.

  • Maintenance is vital to lighting efficiency. Light levels decrease over time because of aging lamps and dirt on fixtures, lamps, and room surfaces. Common lamps, especially incandescent and fluorescent lamps lose 20%–30% of their light output over their service life. Dirt collects on surfaces, which reduces the amount of light they reflect. Together, these factors can reduce total illumination by 50% or more, while lights continue drawing full power. When auditing your home, take note of lighting devices’ general state.

4) Appliances and Home Electronics - If you live in a typical US home, your appliances and home electronics are responsible for about 20% of your energy bills (other industrialised countries have similar percentages). These appliances and electronics include the following: clothes washers and dryers, computers, dishwashers, home audio equipment, refrigerator and freezers, room air conditioners, televisions, DVD players, and VCRs, water heaters.
  • An increasing number of electrical appliances consume electricity when they are not in use. In some cases this is because the appliance is on ‘stand-by’, ready to be powered up by a remote control handset. Many appliances consume electricity even when they appear to be turned off, because they contain transformers that are still connected to the power supply.
5) Hot water - You can reduce your monthly water heating bills by selecting the appropriate water heater for your home and by using some energy-efficient water heating strategies. To conserve hot water, you can fix leaks, install low-flow fixtures, and purchase an energy-efficient dishwasher and clothes washer.
  • It's commonly assumed that washing dishes by hand saves hot water. Wrong: you can consume less energy with an energy-efficient dishwasher when properly used and when only operating it with full loads.
  • Unlike dishwashers, clothes washers don't require a minimum temperature for optimum cleaning. Therefore, to reduce energy costs, you can use either cold or warm water for most laundry loads. Cold water is always sufficient for rinsing. Inefficient clothes washers can cost three times as much to operate than energy-efficient ones. Also, front-loading machines use less water and, consequently, less energy than top loaders. .
  • If you have an electric water heater, you can save an additional 5%–12% of energy by installing a timer that turns it off at night when you don't use hot water and/or during your utility's peak demand times.
  • When auditing your home, carefully consider all these elements (leaks, appliances’ features and use, timers, etc.). Water heating, in fact, can account for 14%–25% of the energy consumed in your home.

The first thing you need to do is find the electric meter outside your home and take an initial reading. In order to complete a comprehensive audit, you will need to read your meter at roughly the same time each day for one month. By subtracting each previous day's reading from the current day's reading, you get the number of kilowatt-hours used during that 24-hour period.

Daily Electric Usage Chart
Note: to obtain daily kilowatt (kWh) usage, subtract
previous day’s reading from current day’s reading
KWh Usage
per kWh
Cost (US$)
Energy Cost
    X 0.7= 
    X 0.7= 
    X 0.7= 
    X 0.7= 
    X 0.7= 
    X 0.7= 
    X 0.7= 

Daily Electric Usage Chart - By adding your daily figures into weekly and monthly totals, you will see how much power your family uses - and when. Using the following chart (which details the amount of energy typically used by major appliances), try to figure out why you used more power at that time.

[click here]

methodological suggestions: as a homework assignment, you could ask students to fill the following questionnaire (in collaboration with their parents/relatives). This could be a first step in collecting detailed data needed for the household energy audit…
  • what could we do to reduce our electricity bill? Students could be invited to work in small groups to make their own energy saving tips list (we provide here, just as an example, the WISE HOME TEST produced by an Australian local authority) - such as... buying the most energy-efficient appliances and light bulbs available or turn off all lights and appliances when not in use.
    WISE HOME TEST [click here]
  • Groups could then compare and discuss in class their conclusions and explaining the reason of their choices. Moreover, they could be asked to report wattage comparison between one standard light bulb and a compact fluorescent light bulb (CFL), and calculate differences in electricity use between two selected households (e.g. a small and a bigger family).
  • Finally, in a 6 months period students could be called to monitor their electricity consumption habits, and monthly report achievements to the class. Best results could be awarded.
results assessment: the success of this pedagogical module on household energy audit can be measured by the following results:

  • informative goal: students know the main energy sources used in their household; they know their household average electricity consumption; they can calculate the amount of carbon dioxide released for electricity consumption; they are aware of existing ways to reduce electricity consumption; they have a general/ basic knowledge of the main renewable energy sources.
  • action goal: students endorse electricity saving measures at home; they are committed to push other people (parents, relatives, friends) adopting energy saving behaviours.