90 likes | 219 Views
Energy Efficiency By: Maura and Austin. What is Energy Efficiency?. Energy efficiency is the percentage of total energy input into an energy conversion device or system that does useful work and is not converted to low-quality, essentially useless heat.
E N D
What is Energy Efficiency? Energy efficiency is the percentage of total energy input into an energy conversion device or system that does useful work and is not converted to low-quality, essentially useless heat Improving energy efficiency of a system involves using less energy to do more work. 84% of all commercial energy used in the United States is wasted, 41% is automatically wasted due to the second law of thermodynamics but 43% is unnecessarily wasted by using fuel-wasting motor vehicles, furnaces etc and living and working in leaky, poorly insulated, poorly designed buildings Unnecessary energy waste costs the U.S. $300 billion a year which is an average of $570,000 per minute. http://www.treehugger.com/cars_transportation/
Improving Energy Efficiency We can’t recycle energy but we can slow the rate at which waste heat flows into the environment when high-quality energy is degraded. For your home: -insulate it thoroughly -eliminate air leaks -equip it with an air-to-air heat exchanger to prevent buildup of indoor pollutants For your office: -collect and distribute waste heat from lights, computers, and other machines to reduce heating bills during cold weather and vent the collected heat outdoors during hot weather to reduce cooling bills -drive a type of air conditioner called an absorption chiller
Saving Energy in Industry Cogeneration-combined heat and power systems in which two useful forms of energy are produced from the same fuel source. These systems have an efficiency of up to 80% compared to the normal 30-40% for coal-fired boilers and nuclear power plants, emit 2/3 less CO2 per unit of energy produced than conventional coal-fired boilers, and in 6-8 years they pay for themselves in saved fuel and electricity. It produces 9% of the electricity in the United States. Replacing energy-wasting electricmotors-most of these motors are inefficient because they run only at full speed with their output throttled to match the task. The cost of replacing these motors with new adjustable-speed drive motors would be paid back in about a year and save an amount of energy equal to that generated by 150 power plants. Switching to high-efficiency lighting http://www.lowimpactliving.com/pages/impact-calculator/impact-calculator?gclid=COyL9eGylpkCFSQMDQodbFxKUw
Saving Energy in Transportation Between 1973-1985, the average fuel efficiency rose sharply for new cars sold in the U.S. and to a lesser degree for pickup trucks, minivans, and SUVs. This occurred because of the government-mandated Corporate Average Fuel Economy (CAFE) standards. But the average fuel efficiency between 1985-2001 leveled off or declined. This was caused by the increased popularity of SUVs, minivans, light trucks, and large autos that produce approximately 20% of U.S. CO2 emissions and failure of elected officials to raise CAFE standards due to opposition from automakers.
Fun Fact By 2020, the cost of solar power is expected to drop by nearly 20% of its cost in 1980. This drop in price is due to both lower upfront costs, lower operating costs and more efficient PV (photovoltaic) systems. NEWSFLASH Do you believe in “clean” coal? Although many people believe in the idea of “clean” coal, there is not a single demonstration large-scale “clean” coal plant in the U.S. today. All new coal plants which have been proposed will release 100% CO2 into the air, just like their predecessors.Three times as many jobs can be produced with an investment in wind power as the same investment in coal power. And an investment in solar power can produce four times as many jobs, and energy efficiency as coal power.
Article Reviews By: Maura Kush “Energy Intensity and Energy Efficiency” Energy efficiency and energy intensity make up energy policy. Energy efficiency refers to the ratio between energy output (services such as light, heat and mobility) and input (fuels). The energy efficiency of a country is not determined by it’s energy intensity. For Japan and the United States, who have comparable technological knowledge and technical energy efficiency, other factors such as energy prices, climate, geography and lifestyles are included in the calculation. Due to these cultural differences, Japan has an energy intensity of roughly half that of the United States. IEA (2000), World Energy Outlook 2000 http://www.iea.org/textbase/papers/2002/improving.pdf Energy Efficiency in the Power Grid by: Bob Fesmire Due to certain environmental, economic and political issues, improving energy efficiency has taken a front row seat in the United States. Much has been done but we are still a long way from the finish line. We may never reach this line but we still need to improve energy efficiency and other energy sources. A coal plant generally wastes anywhere from 65-40% in the transformation of coal to usable energy. As we rotate our focus from coal, uranium and natural gas to renewable resources such as wind and sun, the concept of energy efficiency is less of a problem. Some energy may be lost but wind and sun are free and inexhaustible. We have not yet taken advantage of the role these resource have to offer. But as we stray away from importing oil, natural gas or even coal from foreign fuel supplies, we increase our dividends from a security standpoint and the less we use, the less we have to buy. http://www.renewableenergyworld.com/rea/news/article/2007/07/energy-efficiency-in-the-power-grid-49238
Questions 1. What is energy efficiency? 2. How did CAFE (Corporate Average Fuel Economy) affect gas emissions from vehicles? 3. Industry can have greater efficiency using what three methods? 4. How could you make your home more energy efficient? 5. How much commercial energy is wasted in the United States?
Bibliography http://images.google.com/imgres?imgurl=http://www.buildbabybuild.net/blog/wpcontent/uploads/2009/02/electricitygrowth1994-2008.png&imgrefurl... http://images.businessweek.com/ss/08/12/1205_internships/image/constellation_energy.jpg http://i.mktw.net/newsimages/NewsCommentary/SpecialReports/TheHeatIsOn/day2energy_bkgd2_660x852.gif