Module 9

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Module 9

• Energy and Environment

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Learning Objectives (1)

• Explain the link between fossil energy
  consumption and environmental quality
• Describe the major features of energy consumption
  in North America
• Amount and trend by type
• Know the present composition of world energy use

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Learning Objectives (2)

• Know what is meant by the terms resources and
  reserves, renewable and non-renewable energy.
• Describe three types of fossil fuel and three
  sources of renewable energy.
• Summarize the environmental impacts of automobile
  use in North America.

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Basic Definitions

• Energy The capacity for doing work
• Work Work is done when a force moves its point
  of application through a distance
• Work Force Distance
• Force An external agency capable of altering the
  state of rest or motion in a body.
• Mass The constant of proportionality between an
  applied force and acceleration

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Energy and Work

• Energy is the capacity to do work. Modern
  societies have been built on an increasingly
  effective harnessing of sources of energy to do
  work, from wood, coal, oil, gas, nuclear and
  beyond.
• Understanding the role of energy and human energy
  use is critical to an analysis of environmental
  issues.

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Fossil Fuels

• Fossil fuels remain the world's most heavily used
  energy sources.
• Petroleum comprises 41 percent of energy use,
• coal comprises about 27 percent, and
• natural gas 22 percent,
• Nuclear power (6) and hydropower (2.5) comprise
  most of the remainder.

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History of Energy Use USA
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Energy and Environment

• Environmental problems such as urban smog, acid
  rain and global climate change are directly
  linked to the combustion of fossil fuels.
• The six major air pollutants are Particulate
  Matter, Sulphur Dioxide, Ozone, Oxides of
  Nitrogen, Lead, and Carbon Monoxide.
• All are the result of the burning of fossil fuels.

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Energy and Economics

• While a variety of environmental problems are
  attributed to the reliance on fossil fuels,
  increased use of energy is a primary indicator
  that a country is developing a higher standard of
  living.
• Greater reliance on energy efficiency and
  alternative sources offers a means of maintaining
  economic development and environmental quality.

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Energy and Economic Growth
In the past half century, global energy growth
has increased in lockstep with economic growth.
TPES Total Primary Energy Supply
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Resources and Reserves

• Resource - a naturally occurring substance of use
  to humans.
• Reserve - the amount of a known deposit that can
  be economically extracted using current
  technology.
• Reserve levels change as technology develops, as
  new discoveries are made, and as profit margins
  change.

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Energy Economics Externalities

• External Costs are those attributable to an
  activity that are not borne by the party involved
  in that activity. They include
• Hidden costs borne by governments, including
  subsidies and R D programs.
• Costs of the damage caused to health and the
  environment, including acid rain damage and
  health impacts.
• The costs of global warming attributable to CO2
  emissions.

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External cost estimates
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Energy Sources

• Non-renewable energy - sources used faster than
  they can be replenished.
• Coal Reserves - 200 yr
• Oil Reserves - 60 yrs
• Natural Gas - 100 yrs

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Renewable Energies

• Renewable energy - continuously present as a
  feature of the physical environment. For example
• An immense amount of energy from the sun strikes
  the surface of the earth every day.
• Hundreds of times the annual energy consumption
  of the global economy. An infinite supply!
• In addition, there is wind and wave power and
  biomass from the sun, as well as geothermal and
  hydro.

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Electrical Energy

• Because electricity is easily transported and its
  uses are so varied, electricity is a major world
  energy source.
• However, most electrical energy is produced from
  burning fossil fuels.

Thermal power generation is also the single
largest consumer of water
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Energy Growth

• Since 1950, energy use increased 400 percent with
  a doubling of world population and a quadrupling
  of Gross World Product.
• The world now consumes the equivalent of 175
  million barrels of oil each day
• equal to 85,000 gallons of gasoline every second.

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Energy and Sustainability

• The necessity of reducing and minimizing the
  environmental impacts of energy use, particularly
  those with potentially worrisome global effects,
  is perhaps the greatest challenge resulting from
  the twentieth century's economic advances.

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Paths to Sustainable Energy

• Energy conservation and energy efficiency
• Over the next half century, energy efficiency
  could satisfy half of the world's energy demand
• Renewable energy
• Renewables could satisfy half of the remaining
  demand
• Reform the transport sector
• Controlling the automobile society

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Renewables

• There is a rapidly expanding global market for
  competitively priced, clean, "green" energy
  services that don't pollute or destroy natural
  resources.
• These green goods include different renewable
  energy options like solar panels, wind turbines,
  biomass power plants, as well as geothermal and
  small scale hydro installations.

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Wind Power

• By the year 2010, Denmark plans to produce half
  its total electricity by wind power.
• They are now the world leader in wind power
  technology, and its a growth industry.
• The technology is being exported worldwide.

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Solar Power space efficient

• Solar energy systems need less space to produce a
  megawatt of electricity than coal-fired power
  when the land devoted to mining is factored in.
• 10 of Arizona desert lands are sufficient to
  meet the whole of USA's electricity needs using
  present-day solar cell technology.
• Most hydropower projects require at least 20
  times as much land per kilowatt-hour as solar
  power does.

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Renewables are Clean

• Photovoltaic power generation has zero emissions.
  For each month of use, a one kilowatt
  photovoltaic system
• prevents 75 kg of coal from being mined
• prevents 150 kg of CO2 from entering the
  atmosphere
• avoids 105 gallons of water from being consumed
• avoids NO and SO2 from being released into the
  environment

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The Automobile Society

• The transportation needs of most North Americans
  are met largely by the automobile.
• The automobile has allowed a freedom of movement
  unequaled in human history, and has become a
  status symbol important to our culture.
• Fueling individual passenger cars now accounts
  for gt25 of the worlds oil consumption.

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Autos and Environment

• It is now apparent that the convenience of the
  automobile has come at a cost to the environment
  and some unintended consequences threaten to
  outweigh the gains.
• The gasoline powered automobile in its present
  form is the cause of a great number of
  environmental problems.

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Exhaust Emissions

• Exhaust emissions from transportation have
  overtaken those from the industrial sector in the
  U.S.
• The environmental impacts of automobile emissions
  include urban smog, acid rain and global warming
• As well there are land use and waste disposal
  concerns related to automobile use.

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Autos, Energy and Materials

• Manufacturing an automobile requires
  approximately 450,000 litres of water, which
  comes in clean and goes out polluted in one way
  or another. 
• The energy required to produce a vehicle is equal
  to about 12 of the energy used by the vehicle in
  its lifetime. 

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Convenient Transportation?

• Americans spend an average 9 hours behind the
  wheel every week.
• The greater mobility of the private car has the
  paradoxical effect of lengthening how far people
  go, rather than saving them time.
• Longer commutes, greater sprawl and worsening
  congestion all translate into lots of time in the
  car.
• Worsening congestion brings deterioration in
  urban air quality, with effects on health and
  quality of life.

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Urban Sprawl

• The ultimate source of the problem is automobile
  dependency created by sprawling patterns of urban
  development.
• Changes in urban land use patterns to reduce
  necessary travel distances, and
• Increased use of alternatives to the automobile
• are the long term solution to the
  environmental problems caused by the automobile. 

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Autos and Land Use

• Patterns of land use have been drastically
  altered by the increased use of the automobile.

Millions of acres of agricultural land, forests
and urban space have been paved over and
dedicated to the automobile. In some inner city
areas, up to 60 of the land area is paved over
for use by cars. 
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Other Land Use Issues

• Paved roadways and parking lots result in more
  rainwater runoff, less groundwater infiltration,
  and increased temperatures in urban areas. 

Large amounts of land are also required to
dispose of used automobiles and automobile parts
such as tires and batteries. Many of these waste
disposal sites have a negative effect on local
air and groundwater. 
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Electric Cars?

• Electric powered vehicles have no tailpipe
  emissions, and can lead to improvements in air
  quality.
• The net environmental impacts of electric
  vehicles depends upon the source of the
  electricity used. 
• Electric cars recharged with electricity from
  coal fired power plants could have net carbon
  dioxide and other emissions far higher than those
  for gasoline powered automobiles. 

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Ethanol a liquid renewable

• Fuel ethanol (or 'Gasohol') is a high octane,
  water-free alcohol produced from the fermentation
  of sugar or converted starch.
• Ethanol is made primarily from grains or other
  renewable agricultural and forest feedstocks.
• Ethanol is blended with gasoline to form an E10
  blend (10 ethanol and 90 gasoline), but it can
  be used in higher concentrations (E85).
• Many newer engines are ethanol-ready.

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Ethanol environmentally-friendly

• The US Clean Air Act Amendments of 1990 mandated
  the sale of oxygenated fuels in areas with
  unhealthy levels of carbon monoxide.
• Since that time, there has been strong demand for
  ethanol blended with gasoline.
• In the United States each year, more than 1.5
  billion gallons are added to improve the
  emissions quality of gasoline.
• Emissions of CO, CO2, SO2 and NO2 are all
  reduced. Smog hazard is also reduced

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Ethanol a viable alternative?

• An acre of U.S. corn yields about 7,110 pounds of
  corn for processing into 328 gallons of ethanol.
  But planting, growing and harvesting that much
  corn requires about 140 gallons of fossil fuels
  and costs 347 per acre.
• Thus, even before corn is converted to ethanol,
  the feedstock costs 1.05 per gallon of ethanol.

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A fair argument?

• Ethanol from corn costs about 1.74 per gallon to
  produce in the US, compared with about 95 cents
  to produce a gallon of gasoline.
• The growers and processors can't afford to burn
  ethanol to make ethanol.
• U.S. drivers couldn't afford it, either, if it
  weren't for government subsidies to artificially
  lower the price.

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Public Transit

• Public transit vehicles such as buses, subways
  and trains consume far less energy and have much
  lower emissions per passenger kilometer than
  automobiles. 
• Governments could promote and support mass
  transit projects to improve urban air quality,
  more efficient use of energy and preservation of
  land resources.

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SUMMARY

• A correlation exists between the amount of energy
  used and economic development (standard of
  living).
• Wood furnished most early energy.
• Fossil fuel consumption and labor-saving machines
  resulted in the Industrial Revolution.
• The enormous growth of fossil fuel use has led to
  serious environmental problems.

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SUMMARY

• Fossil Fuels are non-renewable
• Reserves are known deposits from which materials
  can be profitably extracted using current
  technology.
• Reserves are ultimately finite and will
  eventually have to be replaced with other
  (renewable) sources.
• Conservation and efficiency could greatly reduce
  energy use without noticeable changes in standard
  of living.