Energy and the Environment

1. Energy and the Environment

2. People around the world seem to have an increasing need for energy; and yet, evidence is mounting that the biosphere cannot sustain activities that produce energy at the expense of the environment. • In this unit you will examine methods used to produce energy and consider how they can be used to balance the need for human progress with environmental stewardship.

3. Electric Hand Dryer Versus Paper Towel • STUDENT ACTIVITY • PAGE 469

4. Energy—The Currency of the Universe • For anything to happen around you or even in your own body, energyis required. • Energy is “The capacity to do work”

5. A Canadian Way of Life • In the early to mid 1990s, new automobile sales shifted significantly from cars to light-duty trucks (e.g., sport-utility vehicles or SUVs).

7. Practice Questions #1-3 • 1. Approximately, 38% - 24% = 14% The change in light-duty-truck sales from 1990 to 1997 is an increase of 14% in new car sales. • 2. Answers may vary. Possible reasons include recreation (needed to pull boats, trailers, etc.), climate conditions (needed for the four-wheel drive feature for safer handling during winter), and work necessity (needed for access to remote worksites). • 3. The reduction in sales of light-duty trucks after 1997 may have been in response to higher gas prices or to a decrease in the number of large vehicles purchased by companies as work vehicles.

8. Gross Domestic Product (GDP) • Gross domestic product is measured in billions or trillions of US dollars so that comparisons can be made among countries. • Industry and the development of natural resources contribute largely to Canada’s GDP; but they also use a great deal of energy. • A measure of a country’s GDP relative to its energy use is called energy intensity

9. Gross Domestic Product (GDP): • the total market value of all goods and services produced by the country in one year; often considered as an indication of a country’s economic output

10. Countries that enjoy a high standard of living tend to have thriving economies and large GDPs.

11. Energy Intensity • the ratio of energy input (in joules) to economic output (in US$); commonly expressed in terajoules(TJ) per billions of US$ of GDP

12. Factors Affecting Energy Use • Climate • Activity • Population

13. Climate • Cold climates = more heat • Warmer climates = more air conditioning • Reduced daylight during winter influence energy use in Canada • The most important aspect of climate that influences energy use is extremes in temperature.

14. Activity • The term activity refers to how much work is being done. • Tonnesof steel manufactured • number of cars produced. • Dollars made from investments. • Activity in the transportation • Regardless of how you measure activity within an economy, energy is required to maintain it.

15. Population • The goal of many developing countries is to industrialize and improve the standard of living for its citizens. • Larger users of energy and of natural resources (e.g., coal, oil, and natural gas) that can be combusted to supply energy. • large populations, drastically increasing the energy required to meet these goals.

17. Energy Efficiency

19. Problem • Calculate the energy efficiency of a water heater that uses 200 J of energy to increase the thermal energy of water 55 J.

20. If you had the chance to consider using a compact fluorescent bulb, you may have noticed that it has a considerably lower power rating (17 W); and it provides the equivalent amount of light as a 60-W incandescent bulb. • The drastic reduction in input energy to produce the same quantity of useful output energy is the result of increased efficiency of compact fluorescent lights compared with incandescent bulbs.

21. Question • Using power ratings, determine the percentage of the total power required by a compact fluorescent bulb versus the total power required by an incandescent light bulb that provides similar output energy.

22. Improvements to energy efficiency from 1990–2003 were estimated to be 883 PJ. If the estimated energy requirement of a small town is 47.9 PJ, • Calculate the energy saved in terms of the number of additional towns that could have their energy needs met due to improvements in efficiency.

23. The use of more efficient electrical devices and other technologies, including the replacement of incandescent lights with compact fluorescent lights, is an important way to offset the increasing need for energy.

24. Alberta’s Energy-Based Economy • Within Canada, Alberta is known for its development of non renewable energy resources of coal, petroleum, and natural gas. • Alberta, however, also produces energy through renewable resources, like wind and hydro. • The role of the energy industry is vital to Alberta’s economy. • Fossil fuels make up over half of the province’s exports. • In addition, royalties paid to the Alberta government by energy companies that extract and process natural resources account for about one-third of the province’s total revenue. • Also, nearly one in six workers in Alberta is employed, either directly or indirectly, by the energy sector

25. Practice • If an automobile engine is 20% efficient, calculate the useful output energy from 1 kg of gasoline containing 44.5 MJ of chemical potential energy.