Personal Energy Consumption

Introduction:

The United States and Candid use more energy per person that all other parts of the world, expect for a few small counties with economies dominated by oil or finance (e.g. Luxembourg and Qatar). Historically, the US and Canada have had abundant, inexpensive energy in the form of wood, coal, and oil; therefore, there was little interest in developing ways of using energy more efficiently.

However, as the price of energy has risen there has been considerable interest in improving the efficiency of energy usage. Government agencies and utility companies provide information about how to improve energy efficiency and also provide financial incentives for doing so. Decisions we make about purchasing and using heating and cooling equipment, water heaters, lighting, transportation, and electrical appliances affect our energy footprint.

There are several complications involved in measuring the quantity of energy contained by various fuels and the amount of energy used by consumers.

1. Fossil fuels and biofuels are mixtures of various chemical compounds and each compound has a specific energy content. For example, gasoline consists of many different derivatives of crude oil but also contains varying amounts of additives, such as ethanol and condiments, such as water. Therefore, gasoline produced from difference sources of crude oil and with different amounts of additive will have difference energy content. Similarly, coal and wood contain varying amounts of water and other compounds
2. The units use to measure different energy sources of energy differ. Kilowatt-hour, calorie, Btu, joule, and therm are all used as ways to measure the quantity of energy.
3. The US differs from nearly all other countries because it does not use the metric system as its standard system of measurement. There fore, a common unit for energy measurement in the US I s the British’s thermal unit (Btu), but the rest of the world uses joule (J) as its standard unit for measuring energy. Review the energy of common energy sources here: https://www.engineeringtoolbox.com/energy-content-d_868.html

Procedure:

This lab consisted of a series of separate actives that examines energy use. Complete each part and record your results in the appropriate Data Sheets/Tables.  

Part 1: Transportation

North Americans drive and fly more than any other people in the worlds. In some urban areas, public transportation such as trains, subways, and buses provide efficient ways to ravel about the city, reducing traffic jams and air pollution.

1. For one week, keep a log of all the miles you travel by the following methods: Foot, Bicycle, Automobile, Public Transport, Plane, and Other.
2. Determine what percentage, approximately, of each of these trips was required for work, school or other necessary reasons. Record your results in Table 1.1

Table 1.1

Part 2: Electrical Appliances

Electrical appliances are very convenient. They allow us to do things quickly and relieve us of distasteful or tedious tasks. Explore how much energy you use as a result of such devices. It is important to recognize that the total energy cost of an appliance also includes the energy necessary to manufacture, distribute, and merchandise the item. You can find the wattage of an electrical appliance on a label on the appliance.

1. Keep a log of all the electrical appliances you use in a one-week period. List each appliance and the number of minutes it was used per week. Record your data and do your calculation in Table 1.2.
2. Determine the wattage of the appliance from its label. If the label does not show the wattage but gives volts and amperes, you can calculate wattage as follows: Watts = Volts X Amperes. Record your data in Table 1.2.
3. If you know the wattage and the number of minutes it was used, you can calculate the number of kilowatt-hours oil energy used, using the calculation below. Record results in Table 1.2
   • Kilowatt-hours used = ((watt rating) x (total minutes used)/60)/ 1000
4. Calculate the cost of the energy used. Cost = kWh used X (cents/kWh). Record results in Table 1.2.

Table 1.2

*Appliances could include: Television, desktop computer, laptop, air conditioner, microwave, oven, etc. 

Part 3: Long-term Costs of Energy Using Appliances

When you make the decision to purchase an appliance, one of the primary things you consider is the purchase price. However, the long-term cost of the appliance includes the amount of energy the appliance will use. The most energy intensive appliances are those that are involved in heating and cooling – furnaces, air conditioners, refrigerators, freezers, and water heaters.

Choose one of these appliances and list the local appliance store (or look the information up online) to obtain information about the cost and energy usage of the appliance. Look at the EnergyGuide label (Figure 1) on the appliances and choose two appliances with similar features but with significantly different energy consumption.

Record your data in Table 1.3.

Figure 1. EnergyGuide Label Example

Image Reference: https://www.e-education.psu.edu/egee102/node/1990

Table 1.3

Post-Lab Questions:

1. What percentage of weekly travel could have been avoided? What changes can you realistically make to reduce your weekly travel energy usage?
2. At current energy prices, which are least expensive to operate: gas or electric appliances? Is the different significant?
3. Were you surprised by the amount of energy you use in a week with electrical appliances? What changes could you make?
4. Many electric utility companies pay rebates to customers who replace old refrigerators, freezers, heating systems, or poorly designed windows? How does the utility company benefit? How do you benefit?
5. How may electrical appliances become more efficient? Explain.