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Energy conservation is the practice of decreasing the quantity of energy used while achieving a similar outcome. This practice may result in increase of Financial Capital , Environmental value, National Security , Personal Security , and Human Comfort . Individuals and organizations that are direct Consumers of energy may want to conserve energy in order to reduce energy costs and promote economic, political and environmental sustainability. Industrial and commercial users may want to increase efficiency and thus maximize profit. On a larger scale, energy conservation is an important element of Energy Policy . In general, energy conservation reduces the energy consumption and energy demand per capita, and thus offsets the growth in energy supply needed to keep up with population growth. This reduces the rise in energy costs, and can reduce the need for new power plants, and energy imports. The reduced energy demand can provide more flexibility in choosing the most preferred methods of energy production. By reducing emissions, energy conservation is an important part of lessening Climate Change . Energy conservation facilitates the replacement of Non-renewable Resources with Renewable Energy . Energy conservation is often the most economical solution to Energy Shortage s, and is a more environmentally benign alternative to increased energy production. ENERGY EFFICIENCY TRENDS IN THE UNITED STATES The U.S. is currently the largest consumer of energy, although at current levels of growth, it is possible that in the future China and India could become the leading energy consumer. The U.S. Department Of Energy categorizes national energy use in four broad sectors: transportation, residential, commercial, and industrial.US Dept. of Energy, "[http://www.eia.doe.gov/emeu/aer/pdf/pages/sec1_3.pdf Annual Energy Report]" (July 2006), Energy Flow diagram Energy usage in the transportation and residential sectors (about half of U.S. energy consumption) is largely controlled by individual domestic consumers. Commercial and industrial energy expenditures are determined by businesses entities and other facility managers. National energy policy has a significant effect on energy usage across all four sectors. Transportation sector The transportation sector includes all Vehicle s used for personal or freight transportation. Of the energy used in this sector, approximately 65% is consumed by Gasoline -powered vehicles, primarily personally owned. Diesel -powered transport (trains, merchant ships, heavy trucks, etc.) consumes about 20%, and air traffic consumes most of the remaining 15%.US Dept. of Energy, " Annual Energy Outlook " (February 2006), Table A2 The Oil Supply Crises of the 1970s spurred the creation, in 1975 , of the federal Corporate Average Fuel Economy (CAFE) program, which required auto manufacturers to meet progressively higher fleet fuel economy targets. The next decade saw dramatic improvements in fuel economy, mostly the result of reductions in vehicle size and weight. These gains eroded somewhat after 1990 due to the growing popularity of Sport Utility Vehicle s, Pickup Truck s and Minivan s, which fall under the more lenient "light truck" CAFE standard. In addition to the CAFE program, the U.S. government has tried to encourage better vehicle efficiency through tax policy. Since 2002 , taxpayers have been eligible for income tax credits for gas/electric hybrid vehicles. A "gas-guzzler" tax has been assessed on manufacturers since 1978 for cars with exceptionally poor fuel economy. While this tax remains in effect, it currently generates very little revenue as overall fuel economy has improved. Another focus in gasoline conservation is reducing the number of miles driven. An estimated 40% of American automobile use is associated with daily Commuting . Many urban areas offer Subsidized Public Transportation to reduce commuting traffic, and encourage Carpooling by providing designated High-occupancy Vehicle lanes and lower tolls for cars with multiple riders. In recent years Telecommuting has also become a viable alternative to commuting for some jobs, but as of 2003 only 3.5% of workers were telecommuters. Ironically, hundreds of thousands of American and European workers have been replaced by workers in Asia who telecommute from thousands of miles away. A vehicle's gas mileage normally decreases rapidly at speeds above 55 miles per hour. A car or truck moving at 55 miles an hour can get about 15 percent better fuel economy than the same car going 65 mph. According to the U.S. Department of Energy (DOE), as a rule of thumb, each 5 mph you drive over 60 mph is similar to paying an additional $0.21 per gallon for gas (at $3.00 per US gallon).http://www.consumerenergycenter.org/transportation/consumer_tips/speeding_and_mpg.html Residential sector The residential sector refers to all private residences, including single-family homes, apartments, manufactured homes and dormitories. Energy use in this sector varies significantly across the country, due to regional climate differences and different regulation. On average, about half of the energy used in the U.S. homes is expended on space conditioning (i.e. heating and cooling). The efficiency of Furnace s and Air Conditioner s has increased steadily since the energy crises of the 1970s. The 1987 National Appliance Energy Conservation Act authorized the Department of Energy to set minimum efficiency standards for space conditioning equipment and other appliances each year, based on what is "technologically feasible and economically justified". Beyond these minimum standards, the Environmental Protection Agency awards the Energy Star designation to appliances that exceed industry efficiency averages by an EPA-specified percentage. Despite technological improvements, many American lifestyle changes have put higher demands on heating and cooling resources. The average size of homes built in the United States has increased significantly, from 1500 ft&2 in , that figure rose to 55% by 2001. As a cheaper alternative to the purchase of a new furnace or air conditioner, most public utilities encourage smaller changes the consumer can make to lessen space conditioning usage. Weatherization is frequently subsidized by utilities or state/federal Tax Credits , as are programmable Thermostat s. Consumers have also been urged to adopt a wider indoor temperature range (e.g. 65 °F in the winter, 80 °F in the summer). Home energy consumption averages:US Dept. of Energy, " Buildings Energy Data Book " (August 2005), sec. 1.2.3
Energy usage in some homes may vary widely from these averages. For example, milder regions such as the southern U.S. and Pacific coast of the USA need far less energy for space conditioning than New York City or Chicago. In milder climates, lighting energy may easily consume up to 40% of total energy. Certain appliances such as a waterbed, hot tub, or pre-1990 refrigerator use significant amounts of electricity. In most residences no single appliance dominates, and any conservation efforts must be directed to numerous areas in order to achieve substantial energy savings. However, Ground Source Heat Pump systems are the more energy efficient, environmentally clean, and cost-effective space conditioning systems available (Environmental Protection Agency), and can achieve reductions in energy consumptions of up to 70%. Best building practices Current best practices in building design and construction result in homes that are profoundly more energy conserving than average new homes. See Passive House , Superinsulation , Self-sufficient Homes , Zero_energy_building , Earthship , Straw-bale Construction , MIT Design Advisor , Energy Conservation Code For Indian Commercial Buildings . Smart ways to construct homes such that minimal resources are used to cooling and heating the house in summer and winter respectively can significantly reduce energy costs! Commercial sector The commercial sector consists of retail stores, offices (business and government), restaurants, schools and other workplaces. Energy in this sector has the same basic end uses as the residential sector, in slightly different proportions. Space conditioning is again the single biggest consumption area, but it represents only about 30% of the energy use of commercial buildings. Lighting, at 25%, plays a much larger role than it does in the residential sector.US Dept. of Energy, " Buildings Energy Data Book " (August 2005), sec. 1.3.3 Lighting is also generally the most wasteful component of commercial use. A number of case studies indicate that more efficient lighting and elimination of Over-illumination can reduce lighting energy by approximately fifty percent in many commercial buildings. Commercial buildings can greatly increase energy efficiency by thoughtful design, with today's building stock being very poor examples of the potential of systematic (not expensive) energy efficient design (Steffy, 1997). Commercial buildings often have professional management, allowing centralized control and coordination of energy conservation efforts. As a result, Fluorescent Lighting (about four times as efficient as incandescent) is the standard for most commercial space, although it may produce certain adverse health effects.Susan L. Burks, ''Managing your Migraine'', Humana Press, New Jersey (1994) ISBN 0-89603-277-9''Cambridge Handbook of Psychology, Health and Medicine'', edited by Andrew Baum, Robert West, John Weinman, Stanton Newman, Chris McManus, Cambridge University Press (1997) ISBN 0-521-43686-9L. Pijnenburg, M. Camps and G. Jongmans-Liedekerken, ''Looking closer at assimilation lighting'', Venlo, GGD, Noord-Limburg (1991)Igor Knez, ''Effects of colour of light on nonvisual psychological processes'', Journal of Environmental Psychology, Volume 21, Issue 2, June 2001, Pages 201-208 Potential health concerns can be mitigated by using newer fixtures with electronic ballasts rather than older magenetic ballasts. As most buildings have consistent hours of operation, programmed thermostats and lighting controls are common. However, too many companies believe that merely having a computer controlled Building Automation system guarantees energy efficiency. As an example one large company in Northern California boasted that it was confident its state of the art system had optimized space heating. A more careful analysis by Lumina Technologies showed the system had been given programming instructions to maintain constant 24 hour temperatures in the entire building complex. This instruction caused the injection of nighttime heat into vacant buildings when the daytime summer temperatures would often exceed 90 degrees Fahrenheit. This mis-programming was costing the company over $130,000 per year in wasted energy (Lumina Technologies, 1997). Many corporations and governments also require the Energy Star rating for any new equipment purchased for their buildings. Solar heat loading through standard window designs usually leads to high demand for air conditioning in summer months. An example of building design overcoming this excessive heat loading is the Dakin Building in Brisbane, California , where fenestration was designed to achieve an angle with respect to sun incidence to allow maximum reflection of solar heat; this design also assisted in reducing interior Over-illumination to enhance worker efficiency and comfort. Recent advances include use of occupancy sensors to turn off lights when spaces are unoccupied, and photosensors to dim or turn off electric lighting when natural light is available. In air conditioning systems, overall equipment efficiencies have increased as energy codes and consumer information have begun to emphasise year round performance rather than just efficiency ratings at maximum output. Controllers that automatically vary the speeds of fans, pumps, and compressors have radically improved part-load performance of those devices. For space or water heating, electric heat pumps consume roughly half the energy required by electric resistance heaters. Natural gas heating efficiencies have improved through use of condensing furnaces and boilers, in which the water vapor in the flue gas is cooled to liquid form before it is discharged, allowing the heat of condensation to be used. In buildings where high levels of outside air are required, heat exchangers can capture heat from the exhaust air to preheat incoming supply air. Industrial sector The industrial sector represents all production and processing of goods, including manufacturing, construction, farming, water management and mining. Increasing costs have forced energy-intensive industries to make substantial efficiency improvements in the past 30 years. For example, the energy used to produce steel and paper products has been cut 40% in that time frame, while petroleum/aluminum refining and cement production have reduced their usage by about 25%. These reductions are largely the result of recycling waste material and the use of Cogeneration equipment for electricity and heating. The energy required for delivery and treatment of fresh water often constitutes a significant percentage of a region's electricity and natural gas usage (an estimated 20% of California's total energy use is water-related.California Energy Commission, " California's Water-Energy Relationship " (November 2005), p.8) In light of this, some local governments have worked toward a more integrated approach to energy and Water Conservation efforts. Unlike the other sectors, total energy use in the industrial sector has declined in the last decade. While this is partly due to conservation efforts, it's also a reflection of the growing trend for U.S. companies to move manufacturing operations offshore. ENERGY CONSERVATION IN THE UNITED KINGDOM main article: Energy Use And Conservation In The United Kingdom Energy conservation in the United Kingdom has been receiving increased attention over recent years. Key factors behind this are the Government's commitment to reducing Carbon Emissions , the projected 'energy gap' in UK electricity generation, and the increasing reliance on imports to meet national energy needs. Domestic housing and road transport are currently the two biggest problem areas. ISSUES WITH ENERGY CONSERVATION Critics and advocates of some forms of energy conservation make the following arguments:
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