Recognize the impact of engineering solutions in an economic context Explain (60
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Recognize the impact of engineering solutions in an economic context Explain (60 to 75 words) an engineering solution for reducing greenhouse gas emissions. Discuss (100 to 125 words) the impact of the above engineering solution in an economic context. Do not discuss the global/social impact of the greenhouse gas emissions. Explain (60 to 75 words) an engineering solution for overcoming lack of clean water in some part of the world. Discuss (100 to 125 words) the impact of the above engineering solution in an economic context. Do not discuss the global/social impact of the lack of cleanExplanation / Answer
1. An engineering solution for reducing greenhouse gas emissions.
Reducing Transportation Activity One way to reduce the GHG emissions of transportation is to reduce transportation activity, or travel, itself. This can often be accomplished without compromising accessibility. One approach to reducing transportation activity is to change land use to decrease the need to travel or enable alternatives to driving. Another approach is to use pricing mechanisms, which can redistribute or increase the cost of travel. A. Changing Land Use to Substitute Accessibility for Travel The geographic distribution of people and places, especially the density of development, strongly influences the demand for transportation. In addition, the way settlements are built—whether neighborhoods have sidewalks or bike paths, whether homes are within walking distance of shops or transit stops—influences both the amount and kinds of transportation. While the relationships between land use, accessibility, and travel are understood at a very general level, much more needs to be known about practical means of improving development patterns to reduce vehicle travel while enhancing accessibility and the quality of life in metropolitan areas.110 For over 50 years automobile-centered cities and towns have been built in the United States. To date, existing tools such as land-use planning, zoning, and transportation infrastructure investments have been primarily used to enhance the mobility provided by motor vehicles, rather than to trade off car travel and accessibility. However, if such tools are used to reduce vehicle travel, their potential can be significant, at least over the longer term. Studies of large-scale metropolitan planning strategies for reducing travel while maintaining accessibility suggest that a combination of land use and transit policies might succeed in reducing vehicle miles traveled in urban areas by about 5 to 7 percent over a period of thirty years, and perhaps 9 to 10 percent if combined with policies to charge for parking and for use of congested roads.111 Modeling and simulation analyses of travel at the neighborhood level suggest that vehicle travel might be reduced 10 to 25 percent by changing the design of subdivision development to more closely resemble the grid street layouts and mixed land uses of pre-WWII communities.
A synthesis of recent studies finds that travel is relatively insensitive to changes in the built environment alone,113 estimating that doubling local densities of population and employment could be expected to reduce vehicle miles traveled by only about 5 percent. Improving regional accessibility (defined by the distances to regional centers) could have a much larger impact. The implication is that major changes in the geography of American cities would be needed, combined with additional pricing policies, to achieve reductions in travel of more than 10 percent. In addition, there are significant barriers to changing U.S. geographic patterns, and major changes will take decades to effect. The possibility of reducing the need for vehicular travel on the order of 10 percent or more without loss of accessibility justifies continuing efforts to develop a better understanding of and better practical tools for influencing transportation via land use. B. Pricing Transportation Transportation costs and their composition are strong determinants of the demand for travel. Changing the costs and their structure can be an effective tool for controlling GHG emissions. Two areas deserve special attention: (1) “internalizing” some of the external costs of transportation, such as air pollution, GHG emissions, and traffic congestion and (2) transferring some of the components of transportation costs now paid as fixed costs, such as automobile insurance, to be paid per mile or per gallon of fuel consumed, while keeping total costs level. Shifting the Incidence of Costs to Reduce Greenhouse Gas Emissions According to recent estimates, the unintended consequences of transportation, including traffic congestion, environmental impacts, uncompensated traffic accident damages, and oil dependence impose very substantial costs on society.114 The full cost of transportation consists of five components: (1) the cost of a vehicle, including its maintenance and insurance, (2) variable costs, such as fuel and tolls, (3) the time of the vehicle operator and traveler, (4) the cost of infrastructure, such as roads, airports, and terminals, and (5) external costs imposed on others, but not directly borne by the traveler or carrier. External costs include air pollution, traffic congestion, GHG emissions, impacts of infrastructure on habitats, and noise. In general, travelers and carriers fully and directly pay the cost of the first three components, directly pay half or more of the cost of infrastructure through user fees such as motor fuel taxes, and pay none of the external costs.
To effectively internalize the external costs of transportation, it is not enough to simply calculate all the unintended costs of transportation and add them up into a per-mile price for vehicle travel or pergallon price for motor fuel. To improve on the current system, economic theory requires that pricing be directly related to the damage done. This implies, for example, that a price for pollutant emissions must distinguish between cleaner and dirtier cars. Pricing must recognize that emissions increase during heavy acceleration and when the car’s air conditioning is running, that the impact on air quality depends on the ambient temperature and other atmospheric conditions, and that the ultimate health damage depends on how many people are exposed. Given the potential complexity of such a pricing system, it is no surprise that most of the external costs of transportation are already partly addressed by non-price policies, such as motor vehicle emissions standards, traffic controls, and automotive fuel economy standards. Despite all of this, there is still some role for externality taxes on vehicle travel or motor fuel, and they could have a significant impact.116 In the United States, highway infrastructure is generally provided as a free public good and paid for by a variety of taxes, including motor fuel, real estate, and sales taxes. Some analysts have argued that free access to highways results in over-consumption of highway transportation.117 It was in part this claim that led the Intermodal Surface Transportation Equity Act (ISTEA) of 1991 to permit greater flexibility in the use of highway trust funds to address mobility issues at the state and local level. Through the Congestion Mitigation and Air Quality (CMAQ) provisions of the ISTEA, for example, the act allows funds previously dedicated to highway construction, maintenance, and operation to be used to mitigate some of the external costs of transportation. This new strategy was continued under the Transportation Equity Act for the 21st Century (TEA-21). These acts were not meant to address all the unintended consequences of transportation for society and the environment. Transportation researchers and planners have long sought an efficient way to price congestion. Congestion leads to excessive engine idling, which wastes fuel and increases GHG emissions. There have been some promising experiments, and advances in telecommunications have greatly reduced the costs of toll collection. Simulation of economically efficient congestion tolls in a large metropolitan area indicated that vehicle miles would decline by about 20 percent on expressways and less than 10 percent on other Reducing Greenhouse Gas Emissions .
2. reducing greenhouse gas emissions in an economic context
Reducing Transportation Activity Mobility gives people access to opportunities and enhances the efficiency of the economy. Reducing transportation activity per se is not a desirable goal. Where there are environmental damages (such as GHG emissions) unaccounted for in private transportation decisions, increasing the cost of travel to reflect these impacts is beneficial from both an economic and environmental perspective. In particular, internalizing the externality of climate change through carbon cap-and-trade systems or direct pricing of the carbon content of motor fuels is an especially attractive option. An even greater impact can be achieved by redistributing certain fixed costs of motor vehicle travel so that they fall on carbon fuels. One example is collecting a portion of vehicle insurance fees as a surcharge on motor fuel. This could reduce GHG emissions from motor vehicles by 8 to 12 percent and could improve the overall economic efficiency of highway transportation. The patterns of land use and development that have evolved over many decades are inefficient from a transportation perspective. If the geography of cities can be transformed to provide equal or greater accessibility with less travel, both the environment and the economy would benefit. Experimentation and modeling analyses indicate that travel reductions of 10 percent may be achievable in the long run, without loss of accessibility. The ability to consistently achieve and sustain such reductions has not been demonstrated in the United States, and much remains to be learned about planning and realizing more transportation-efficient patterns of land use. Policy Options There are plenty of practical and effective policies for reducing transportation’s GHG emissions. The policies described in this report are not the only policies that can be effective; rather, they are representative of the kinds of policies a comprehensive strategy would include. A reasonable combination of policy measures should be able to reduce U.S. transportation sector CO2 emissions by 20 to 25 percent by 2015 and by 45 to 50 percent by 2030 in comparison to a transportation future without any efforts to control carbon emissions. If the demand for transportation energy use continues to grow at 2 percent per year through 2030, achieving these reductions will result in CO2 emissions in 2030 that are about the same as the current level.
Forecasts to 2030 confirm that the rapid growth in transportation demand, oil use, and GHG emissions over the past few decades is expected to continue. For example, the EIA’s International Energy Outlook 2009 (IEO2009) projects that, without changes in ongoing trends, the transportation energy demand of the nations outside of the Organization for Economic Cooperation and Development (OECD) will grow by about 90 percent from 2006 to 2030, an annual growth rate of 2.7 percent (EIA, 2009a). Even with expected slower growth in the developed nations,4 the total growth for the world transportation sector for 2006 to 2030 will be 39 percent, growing from about 92 quadrillion Btus (quads) in 2006 to 128 quads in 2030.5 The International Energy Agency (IEA) forecasts are even more bullish on transportation growth—its baseline forecast has transportation energy increasing by nearly 50 percent in 2030 and a remarkable 100 percent by 2050, compared to 2007 levels (IEA, 2009b). Most of this new consumption of 36 to 46 quads in 2030 is expected to be oil, placing pressure on the world’s oil supply capacity. If conventional sources fail to meet this demand, the most likely alternatives will be heavy oil, oil sands, oil shale, and liquids from natural gas and coal. These are carbon-intensive fuels that would add to GHG emissions. The IEA forecast foresees a move to high-carbon fuels after 2030, and its estimated transportation GHG emissions for 2050 are about 113 percent higher than those in 2007
Energy prices and economic growth rates (both global and for individual countries), which also create uncertainty in future freight traffic patterns, energy use, and GHG emissions. • The policy decisions made by developed and developing economies. Policies that seriously address GHG mitigation will also greatly reduce transportation energy use and petroleum demand.
Energy Security and Oil Dependence An improvement in energy security is a major potential co-benefit of reducing transportation’s GHG emissions. The U.S. transportation system’s dependence on petroleum makes the U.S. economy vulnerable to significant excess economic costs on the order of hundreds of billions of dollars per year (Greene, 2010a), and interferes with U.S. national security and foreign policy objectives (CFR, 2006). A comprehensive strategy of increased energy efficiency, alternative energy sources, and increased domestic supplies of energy for transportation can achieve meaningful energy independence (NCEP, 2004), reducing economic harm from supply shocks and high oil prices. Mitigating transportation’s GHG emissions can make the single most important contribution to achieving that goal because transportation consumes 70 percent of all U.S. petroleum use
3. Engineering Solution for overcoming lack of clean water
Today, almost 900 million people do not have access to safe drinking water—about one in every eight people. The global consumption of water is doubling every twenty years, twice the rate of population growth, and it is estimated that in 2025, at least 3 billion people will be living in areas where it will be difficult or even impossible to meet basic water needs. How can this happen? There are increasing demands on the world’s water supply. Population growth, water-intensive agriculture and economic development are using water faster than it can be replenished. In addition, freshwater resources are in jeopardy due to increasing pollution and climate change. Water is essential to our lives. We need water to drink, to bathe and to grow food. For most of us, the supply of water seems to be endless. We can simply turn on the faucet any time of the day, any day of the year. Throughout the world, however, millions of people must walk for hours each morning to bring water to their homes. In developing countries, lack of clean water is a devastating and often deadly problem. Many times people are forced to draw water from a dirty pond or contaminated river, contributing to poor health and disease. Drinking unclean water causes millions of deaths each year from diseases such as diarrhea, hepatitis, cholera, typhoid and parasites. Access to safe water is a basic human right. It can improve the health, economy and social well-being of a community. We must use water wisely and responsibly to ensure that in the future everyone will have access to drinking water that is affordable and safe. What are some things you can do? Where does our water come from? Most of the Earth’s water is undrinkable. Although 70 percent of the planet’s surface is water, almost all of it is saltwater in the oceans. Only 3 percent of the world’s freshwater is safe for drinking, and 97 percent of that is frozen in glaciers. That leaves us with less than 1 percent usable water from lakes, rivers and underground sources! Why can’t we use water from the ocean? Removing salt from water, called desalination, would greatly help with the world’s water needs, yet because it is so expensive and requires a large amount of energy, most countries cannot afford to do it. But with water shortages threatening populations, desalination may become a necessity in the future.
ACCESS TO CLEAN WATER? Poorly managed water resources Possibilities and Options are also a source of conflict—over scarce access in water distressed regions—and environmental degradation. So addressing water needs can have a huge development payoff that reaches beyond health. From protecting watershed ecosystems to water supply management, investing in water and sanitation has a payoff that goes beyond just the infrastructure. Easily accessible clean water means that women and girls do not have to walk miles each day to lug heavy buckets of usually dirty water for use at home. Instead they can go to school or engage in productive activities. And as communities learn to manage their water resources, access can often promote critical economic activities, from gardening to food production to industry. —Mark Malloch Brown, Former Deputy Secretary-General of the United Nations
We will not be able to solve water problems unless we think in a new way—unless we move away from the belief that the answer is one more massive concrete dam blocking our rivers to the idea that we must meet basic human and environmental needs for water; let all affected stakeholders play a role in making decisions; refocus on what we do with the water and how efficiently we do it and use appropriate economic approaches to pay for water and for the costs to us and the environment of using that water. —Peter H. Gleick, President of the Pacific Institute
4.
Lack of clean water is responsible for more deaths in the world than war. About 1 out of every 6 people living today do not have adequate access to water, and more than double that number lack basic sanitation, for which water is needed. In some countries, half the population does not have access to safe drinking water, and hence is affl icted with poor health. By some estimates, each day nearly 5,000 children worldwide die from diarrhearelated diseases, a toll that would drop dramatically if suffi cient water for sanitation was available. It’s not that the world does not possess enough water. Globally, water is available in abundance. It is just not always located where it is needed. For example, Canada has plenty of water, far more than its people need, while the Middle East and northern Africa — to name just two of many — suffer from perpetual shortages. Even within specifi c countries, such as Brazil, some regions are awash in fresh water while other regions, affl icted by drought, go wanting. In many instances, political and economic barriers prevent access to water even in areas where it is otherwise available. And in some developing countries, water supplies are contaminated not only by the people discharging toxic contaminants, but also by arsenic and other naturally occurring poisonous pollutants found in groundwater aquifers. Water for drinking and personal use is only a small part of society’s total water needs — household water usually accounts for less than 5 percent of total water use. In addition to sanitation, most of the water we use is for agriculture and industry. Of course, water is also needed for ecological processes not directly related to human use. For a healthy, sustainable future for the planet, developing methods of ensuring adequate water supplies pose engineering challenges of the fi rst magnitude. PROVIDE ACCESS TO CLEAN WATER Many water supplies are contaminated not only by people discharging toxic contaminants, but also by arsenic and other naturally occurring poisonous pollutants found in groundwater aquifers. Provide access to clean water 20 www.engineeringchallenges.org Of course, by far most of the world’s water is in the oceans, and therefore salty and not usable for most purposes without desalination. About 3 percent of the planet’s water is fresh, but most of that is in the form of snow or ice. Water contained in many groundwater aquifers was mostly deposited in earlier, wetter times, and the rate of use from some aquifers today exceeds the rate of their replenishment. “Overcoming the crisis in water and sanitation is one of the greatest human development challenges of the early 21st century,” a recent U.N. report warns. [United Nations Development Programme, p. 1] Where does our water supply come from? From digging wells to building dams, engineers have historically been prime providers of methods for meeting the water supply and quality needs of society. To meet current needs, which increasingly include environmental and ecosystem preservation and enhancement demands, the methods will have to become more sophisticated. One large-scale approach used in the U.S., China, India, and other countries has been to divert the fl ow of water from regions where it is plentiful to where it is scarce. Such diversion projects provide some short-term relief for cities, but do not appear practical as widespread, long-term, ecologically sound solutions, and this method generally will not be able to meet agricultural needs. Furthermore, diverting water to some people often means less for others and can become an explosive political issue. What is desalination? Desalination is extracting the salt from seawater. Desalination is not a new idea and is already used in many regions, particularly in the Middle East. Saudi Arabia alone accounts for about a tenth of global desalination. Israel uses desalination technology to provide about a fourth of its domestic water needs. Modern desalination plants employ a method called reverse osmosis, which uses a membrane to separate the salt. More than 12,000 desalination plants now operate in the world. But desalination plants are expensive to build and require lots of energy to operate, making desalination suitable mainly for seaside cities in rich countries. It therefore has limited value for impoverished countries, where water supply problems are most serious. New technologies that would lower energy use — and therefore costs — might help desalination’s contribution. One potentially useful new approach, called nano-osmosis, would fi lter out salt with the use of tiny tubes of carbon. Experiments have shown that such tubes, called nanotubes because their size is on the scale of nanometers, have exceptional fi ltering abilities. Even with such advances, though, it seems unlikely that desalination alone will be able to solve the world’s water problems. Other approaches will be needed
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