45:211: environmental geography module 9 energy and environment

45:211: Environmental Geography

Module 9

Energy and Environment


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


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.


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


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.


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.


History of Energy Use: USA


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.


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.


Energy and Economic Growth

Energy Use and Economic Growth (1960-1990)

1

10

100

1000

10000

1 10 100 1000 10000

GDP

TP

ES

USA

Canada

Sweden

India

In the past half century, global energy growth has increased in lockstep with economic growth.

TPES = Total Primary Energy Supply


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.


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.


External cost estimates


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


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.


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


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.


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.


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


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.


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 it’s a growth industry.– The technology is being exported worldwide.


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.


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


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 >25% of the world’s oil consumption.


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.


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.


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.


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.


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.


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.


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.


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.


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.


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


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.


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.


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.


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.


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.

45:211: environmental geography module 9 energy and environment

Documents

energy efficiency

nonrenewable energy

role of energy

percent of energy use

increased use of energy

human energy use

history of energy use

fossil energy consumption