31) Offshore wind farms are being seriously considered because ________.
A) they are more aesthetically pleasing
B) they do not interfere with bird migration routes
C) wind speeds are higher and turbulence is lower
D) development of land for human use is pushing wind farms to open water
E) maintenance costs are less than they are on land
32) The current practice of geothermal power generation may not provide a practical renewable
energy source because ________.
A) in many cases, the heated groundwater is used much faster than it is recharged
B) in many cases, the magma is used faster than it is recharged
C) power plants have high maintenance costs
D) in some instances, pollution emissions can be very high
E) geologically heated groundwater is unsuitable for these plants and must be purified first
33) Potential energy sources from oceans rely on ________.
A) chemiluminescent bacteria
B) the motion of currents, waves, and tides, and ocean thermal energy
C) solar reflection
D) lightning strikes in saltwater
E) magnetic field generators
34) Which of the oceanic energy sources is likely to have the most serious negative impacts on
marine and estuarine ecosystems?
A) sluice-based tidal energy
B) in-stream tidal energy
C) wave energy
D) offshore wind energy
E) ocean thermal energy conversion
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35) Although solar-PV-generated electricity as a power source is cleaner than burning fossil
fuels, it cannot be stored easily in large quantities for use when and where it is needed. A similar
disadvantage affects ________ energy.
A) hydro
B) wind
C) biomass
D) nuclear
E) hydrogen fuel
36) One difficulty with the process of using hydrogen as a power source is that it ________.
A) is not properly understood
B) is less efficient than fossil fuels
C) requires a fuel that is a nonrenewable resource
D) requires an energy investment to begin the process
E) has highly volatile and dangerous components
37) Whether a hydrogen–based energy system is environmentally cleaner than a fossil fuel
system depends on ________.
A) the car driven
B) the source of the oxygen used for the process
C) how the hydrogen is extracted
D) governmental incentives for research
E) This is not correct; a hydrogen system will always be cleaner than a fossil fuel system.
38) One advantage of using hydrogen fuel cells is ________.
A) the potential for the production of greenhouse gases
B) the ease of transporting and storage
C) the energy efficiency
D) that they are nonpolluting
E) the low impact on atmospheric ozone
39) The chemical product of using hydrogen as an energy source is ________.
A) carbon dioxide
B) sulphur dioxide
C) water
D) incineration
E) electrolysis
40) A major advantage that hydrogen–generated electricity has over other new renewable energy
sources is that it ________.
A) is less expensive
B) creates greenhouse gases but no acid deposition
C) can be produced where and when electricity is needed
D) converts the kinetic energy of earth processes to electrical energy
E) already has an infrastructure in place for using hydrogen as fuel
41) Wind is a major energy resource in ________.
A) Alberta and Saskatchewan
B) Ontario
C) Quebec
D) British Columbia
E) Yukon
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17.5 True/False Questions
1) Today’s economies are powered by fossil fuels, with four-fifths of all primary energy coming
from oil, coal, and natural gas.
2) Renewable energy sources have received many more subsidies, tax breaks, and other
incentives from governments compared to conventional sources.
3) Biomass was the first energy source used by humans.
4) Half of all new cars in Brazil are flexible-fuel cars.
5) Biomass is the least–expensive fuel for burning in power plants.
6) Hydropower is renewable and produces less pollution than fossil fuel use.
7) Recent IAEA data clearly prove that nuclear power produces far fewer emission pollutants
than fossil fuels.
8) Cellulosic ethanol is a new and inexpensive way to convert low-grade ethanol to cellulose.
9) Canola is the major Canadian crop that is used to produce ethanol.
10) The new renewables, while promising, currently provide only about one–half of our total
energy supply.
11) The most rapidly growing new renewable energy source is wind power.
12) The most common form of solar energy collection is passive solar collection.
13) Offshore sites seem to hold great promise for future wind farms.
17.6 Essay Questions
1) Why is it urgent that we develop alternatives to fossil fuels?
2) Is the use of biomass for power generation economically feasible and sustainable? Why or
why not?
3) Explain nuclear fusion and its role in power generation.
4) Explain a nuclear meltdown.
5) Compare the environmental effects of coal and uranium as power sources.
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6) Discuss the advantages and disadvantages of wind power.
7) In general, what has spurred the use of renewable energy, and what are the benefits of its use
in environmental and economic terms?
8) Compare and contrast passive solar collection and active solar collection.
9) What is geothermal power? What are the advantages and disadvantages of the use of
geothermal power?
10) Describe some of the possible ocean energy sources.
17.7 Scenario-Based Questions
Read the following scenario and answer the questions below.
The United States consumes 25% of the world’s petroleum. To reduce this number, the United
States wants to replace transportation-related petroleum with alternative fuels. Europe and
Canada followed later. For diesel vehicles, biodiesel made from vegetable oil or animal fat is an
economical alternative to petroleum–based fuels. It is safe, biodegradable, nontoxic, and has the
highest energy balance of any liquid fuel. Unlike unrefined oils that can be burned directly as
fuels, biodiesel can be used in conventional diesel engines without engine modification. It
reduces wear without compromising performance because of its high lubricity. It is renewable
and emits far less air pollution when combusted as compared to petrodiesel. The raw material
used to produce biodiesel exists in billions of gallons of vegetable oil used by restaurants each
year, as well as in crops. Processing biodiesel yields an added benefit; its by–product, glycerine,
is used to make soap. Although biodiesel burns well in pure form (B100), commonly it is
blended with petrodiesel in mixtures such as B20 and B5, which reduce toxic air pollution
proportional to their biodiesel content. Biodiesel is currently available at more than 2000 filling
stations in Germany, and is the preferred fuel in Europe. In the United States, there are more than
600 filing stations that sell biodiesel. Demand is increasing on account of tax incentives as well
as the increased price and decreased availability of petrodiesel. For example, Ontario has
eliminated the 14-cent-per-litre provincial tax on biodiesel. France is currently the country where
biodiesel is used the most. There, it is being used in home heating as well as in vehicles. In the
United States, more than 600 domestic fleets use biodiesel, including the U.S. military, NASA,
Yellowstone National Park, and local governments. In Vancouver, the Biodiesel Cooperative
enables its members to purchase biodiesel. Toronto Hydro uses biodiesel in its fleets, Société de
transport de Montréal (STM) and Saskatoon Transit Services are testing both B20 and B5 in their
city buses. Musicians Neil Young, Bonnie Raitt, and Willie Nelson fuel their tour buses with
biodiesel. Nelson sells his own brand, BioWillie Biodiesel, at many truck stops in the United
States. Because biodiesel can be manufactured locally in Canada and the United States, fuel
transportation costs are low, and dependence on foreign petroleum and the need for domestic oil
exploration and development of sensitive wildlife areas, such as the North Shore of Alaska and
the Yukon can be reduced when biodiesel is used as an alternative fuel.
1) Compared to other uses of biomass, biodiesel represents one of the best environmental
alternatives to fossil fuels because it ________.
A) can be manufactured without the development of additional cropland agriculture
B) requires less processing than other forms of biomass
C) is the only form of biomass that reduces fossil fuel use
D) is the only form of biomass that is renewable
E) is the most available
2) The United States ________.
A) gives tax credits to restaurants that reuse vegetable oil
B) aims to reduce dependence on foreign oil
C) permits oil drilling in the Arctic National Wildlife Refuge/Vuntut National Park
D) permits oil drilling in Juan de Fuca Strait
E) mandates the gradual phaseout of diesel engines
3) Vegetable oil ________.
A) is a necessary ingredient in biodiesel
B) must be processed into biodiesel to operate engines
C) is a fossil fuel
D) is nonrenewable
E) can be used to make glycerine as well as burned as fuel
4) As a fuel, biodiesel ________.
A) is a beneficial alternative for buses and trucks
B) requires moderate engine retrofitting prior to use
C) can be widely used in the existing private car fleet
D) is less efficient than petrodiesel because it has a low energy yield
E) has been met with considerable resistance by American farmers
5) A major barrier preventing more widespread use of biodiesel is ________.
A) the lack of government support
B) a readily available supply of domestic petroleum
C) the lack of support from the public
D) political and economic inertia and current lack of abundant fuelling stations
E) the excessive cost
6) Biodiesel is to ________ as ethanol is to gasoline.
A) vegetable oil
B) petrodiesel
C) gasohol
D) glycerine
E) petroleum
7) B5, B10, and B20 represent ________.
A) new vitamins recently isolated from sugar cane bagasse
B) synthetic compounds that can be mixed with fossil fuel to give more energy
C) various ratios of biodiesel to petrodiesel in alternative vehicular fuels
D) bacterial strains used to ferment corn to make ethanol
E) varieties of broccoli used in the production of cellulosic ethanol
Read the following scenario and answer the questions below.
Southern Alberta, the lower half of Saskatchewan, and the southern part of Manitoba are the best
locations for wind power (see Figure 17.27). People in these areas wonder if there is enough
wind to make such an investment worthwhile. An average wind speed of 14 to 20 km per hour is
sufficient for most sizes of wind turbines. The power available in the wind is proportional to the
cube of its speed, which means that doubling the wind speed increases the available power by a
factor of eight.
8) If the wind speed averages 19 km/h on one hill and 17 km/h on another hill, then a turbine
operating on the first hill could, in theory, generate about ________% more electricity than a
turbine on the second hill.
A) 1
B) 10
C) 25
D) 33
E) 50
9) Suppose there are two 65–kilowatt wind turbines predicted to generate 200 000
kilowatt–hours of wind energy each year, displacing conventional electric generation that would
otherwise produce 140 tons of carbon dioxide—the primary source of global climate change.
Wind energy from these first two turbines also avoids the annual production of 362 kg of
nitrogen oxides and 861 kg of sulphur dioxide, which are the major ingredients ________.
A) in acid rain and ground–level ozone or smog
B) damaging the ozone layer
C) in water pollution
D) causing eutrophication
E) in fertilizers
10) The entire output of the Cowley Ridge Wind Plant in Southwestern Alberta was quickly sold
to subscribers, and further wind energy parks were soon built in other places. Most of the
distribution has gone to businesses, universities, and provincial agencies. This means that
________.
A) consumers still do not trust alternative energy sources
B) many groups have recognized the economic and environmental benefits of alternative energy
sources
C) the costs associated with renewable energy sources can be borne only by large groups
D) very few large institutions are concerned about the pollution and environmental degradation
associated with using wind to generate electricity
E) renewable energy sources are not yet efficient enough to be used by homeowners
11) Environmentalists have been concerned about the effects of the wind turbines on local and
migratory birds. The wind farm at Cowley Ridge Wind Plant is situated in an area of high raptor
use, and some birds have died there from collisions with the turning rotors. Detailed studies
show that in most areas, such deaths will be less than 1% of human–caused deaths on account of
factors such as tall buildings and glass doors and windows. Therefore, it is probably true that
________.
A) wind turbines are a serious wildlife hazard
B) small–bird mortality will increase far more than large–bird mortality near wind farms
C) wind turbines will be safer for wildlife than coal–powered electrical–generating plants
D) the most serious hazard from wind turbines will be problems with airplanes
E) wind farms will be hazardous to domestic pigeons
12) Electricity production and consumption are most commonly measured in kilowatt–hours
(kWh). A kilowatt–hour is one kilowatt (1000 watts) of electricity produced or consumed for one
hour. A 10–kW wind turbine can generate about 10 000 kWh annually at a site with wind speeds
averaging 19 kilometres per hour, or about enough to power a typical household. In just such a
site, the 250–kW turbine installed at the Canadian Tire retail store in Welland, Ontario, provides
an annual average of over ________.
A) 250 kW
B) 250 mW
C) 2 500 kW
D) 25 000 kW
E) 250 000 kW
13) Electricity production and consumption are most commonly measured in kilowatt–hours
(kWh). A kilowatt–hour is one kilowatt (1000 watts) of electricity produced or consumed for one
hour. A 10–kW wind turbine can generate about 10 000 kWh annually at a site with wind speeds
averaging 19 kilometres per hour. This means that the turbine produces on average about
________% of its nominal generating potential (i.e., the energy that could be theoretically
produced if the turbine worked at 100% of its capacity all the time).
A) 30%
B) 50%
C) 90%
D) 1%
E) 10 %
14) Traditional uses of wind energy did NOT include ________.
A) draining wetlands
B) irrigating crops
C) producing electricity
D) transportation
E) grinding grain
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