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1、<p><b>  附 錄 </b></p><p><b>  附錄A:</b></p><p>  LOW ROLLING RESISTANCE TIRES</p><p>  According to the report,80% or more of a car’s fuel energy is wa

2、sted by friction and other such losses. 1.5 to 4.5% of total gasoline use could be saved if allreplacement tires in use had low rolling resistance. About 237 million replacement tires are sold in the U.S. each year – non

3、e has rolling resistance labeling.</p><p>  1. America’s Fuel Use, Its Impacts,and Opportunities for Savings</p><p>  The environmental impacts of America’s gasoline use are profound. With over

4、160 million passenger cars and light trucks on the road, we burn about 126 billion gallons of gasoline per year. Our fuel use continues to rise about 3% annually, propelled by continued increases in total number of vehic

5、les, rising average distance driven per car, and falling average fuel economy.</p><p>  Today, light-duty vehicles (cars & light trucks) are responsible for about 20% of the nitrogen oxides, 27% of the v

6、olatile organic compounds, 51% of the carbon monoxide, and roughly 30% of all the carbon dioxide (the main greenhouse gas) emitted from human activities nationwide. Rising fuel use also has enormous implications for prot

7、ection of wilderness and public lands (vulnerable to increased exploration), water resources (vulnerable to tanker and pipeline accidents), and national security. So</p><p>  One of the most promising opport

8、unities for fuel savings across the entire fleet of existing vehicles is to utilize low rolling resistance tires instead of standard replacement models. This change improves the inherent efficiency of the vehicle, automa

9、tically saving fuel over the typical 30,000 to 50,000 mile lifetime of a set of tires.</p><p>  This report examines the opportunity for saving gasoline through use of improved tire technology and recommends

10、 particular tire models for which our initial test data suggest environmental advantages. Its findings are applicable to government and corporate fleet managers as well as individual tire buyers.</p><p>  2.

11、 How Tires Can Reduce Fuel Consumption</p><p>  According to the National Academy of Sciences, about 80 to 88% of the energy in a vehicle’s gasoline tank is wasted in various thermal, frictional, and standby

12、 losses in the engine and exhaust system. This leaves only about 12 to 20% of the potential energy actually converted to vehicle motion. One of the key ways to improve that efficiency is to reduce the rolling resistance

13、of vehicle tires. This is not a measure of a tire’s traction or “grip” on the road surface, but rather simply indicates h</p><p>  Detailed modeling conducted by the National Renewable Energy Laboratory conc

14、luded that a 10% reduction in tire rolling resistance should yield fuel savings of about 1 to 2%, depending on driving conditions and vehicle type. According to research for the California Energy Commission, about 1.5 to

15、 4.5% of total gasoline use could be saved if all replacement tires in use had low rollingresistance. This translates roughly into average savings of up to 30 gallons of gasoline savings per vehicle per y</p><

16、p>  As part of their efforts to meet Federal fuel economy standards, automakers routinely specify low rolling resistance tires on their new vehicles. Between 1980 and 1994, the lowest rolling resistance tire models av

17、ailable achieved a 48% reduction in rolling resistance, and have likely continued to improve thereafter. These original equipment (OE) tire models are occasionally available in the replacement tire market, but often only

18、 by special order. In general, the tires marketed to the replacemen</p><p>  Unfortunately both OE and replacement tires lack any sort of rolling resistance labeling currently, so fleet managers and consumer

19、s that wish to buy highly energy-efficient tires when their first set of OE tires wear out have been stymied. Even when tire makers claim that particular replacement models are more fuelefficient than others, they do not

20、 always use consistent test methods or independent laboratory data to back up those claims. About 237 million replacement tires are sold in the U.S. e</p><p>  In 2002, the Energy Foundation funded Ecos Cons

21、ulting to analyze the tire market, select representative models for rolling resistance testing, and work with Green Seal to recommend particular models that perform well while achieving low rolling resistance. Those find

22、ings are being published for the first time in this Choose Green Report. Additional background on Ecos Consulting’s key findings can be found in a separate report prepared for the California Energy Commission, available

23、at www.energy</p><p>  3. Balancing Tire Resistance and Other Considerations</p><p>  The manufacture of tires, like other industrial processes, involves material extraction and production, as w

24、ell as energy consumption and the emission of various pollutants. Each of these manufacturing stages impacts the environment in different ways. However, tires, like a number of other consumer products, are actually respo

25、nsible for more environmental impacts in their use and ultimate disposition than in their manufacturing. They significantly impact the amount of fuel consumed by the vehicl</p><p>  An analysis conducted by

26、Italian tire manufacturer Pirelli (Figure 1) revealed the dominance of tire use in overall life-cycle energy consumption. Fully 82% of the lifecycle energy use occurs from the tire’s contribution to vehicle fuel use, com

27、pared to roughly 18% associated with obtaining the raw materials and manufacturing the tire itself. Thus, a tire’s rolling resistance is likely to be a larger factor in its life-cycle environmental impact than its compos

28、ition, longevity, or ultimate fate,</p><p>  This report places greatest significance on the measured rolling resistance of tires, followed closely by consideration of the tire’s expected longevity and perfo

29、rmance characteristics. A tire with high rolling resistance can cause profound environmental impact, even if it capably grips the road and lasts for 80,000 miles. By contrast, a very low rolling resistance tire may not b

30、e worth recommending if its lifetime is unusually short or test data indicate that it provides poor traction.</p><p>  Every tire currently on the market represents a balance between a wide assortment of des

31、ired performance characteristics and price (we surveyed tires ranging from $25 to over $200 per tire). Careful balancing of these characteristics can yield not only a high-performing tire, but also one that is better for

32、 the environment than others currently available on the market.</p><p>  4.Rating Tire Rolling Resistance and Related Factors</p><p>  Rolling resistance has traditionally been measured through

33、an official Society of Automotive Engineers (SAE) test procedure known as J1269. It measures the force required to roll a tire against a dynamometer at a fixed speed of 50 miles per hour. A newer procedure, SAE J2452, pr

34、omises improved accuracy by assessing rolling resistance at a variety of speeds, but no independent laboratory currently has the capability to conduct such testing in-house. As a result, all of our testing was conducted

35、a</p><p>  The highest and lowest rolling resistance tires we tested differed in efficiency by 60%, indicating that tire choice can have a bigger impact on fuel economy than most people realize. Rolling resi

36、stance differences of 20 to 30% are not uncommon among tires of an otherwise similar size, type, and level of performance. This means an individual vehicle could save up to 6% of its gasoline use if it were fitted with v

37、ery efficient tires, paying for the modest additional cost of low rolling resistance</p><p>  All tires have imprinted information on their sidewalls indicating size, type, load, and speed ratings, as descri

38、bed in Figure 2. The majority of tire models employ a “P” designation for passenger vehicle use, but some bear the “LT” designation for use with light trucks. In general, “P” tires appear to be gaining in popularity rela

39、tive to “LT” tires of a given size.</p><p>  In addition, the U.S. Department of Transportation requires each manufacturer to grade its tires under the Uniform Tire Quality Grading System (UTQGS) and establi

40、sh ratings for the following characteristics: tread wear, traction, and temperature resistance. Unfortunately, the ultimate results published for each tire model are less “uniform” than they should be. The government spe

41、cifies how each test should be conducted and prevents a manufacturer from claiming better performance than measured. H</p><p>  Given the variability of ratings and the number of relevant factors, we have co

42、mpiled our own composite metrics of performance for assessing tires, including the Federal ratings noted below and a variety of other published data.</p><p>  5.Rolling On to the Future</p><p> 

43、 Efforts to differentiate replacement tires on the basis of rolling resistance are still in their very early stages. Without data on the rolling resistance of all tire models across a range of sizes, it is impossible to

44、say for sure if the models identified in this report represent the most efficient models or simply a subset of them. For now, consumers and fleet managers can start with the data shown here and request additional informa

45、tion directly from retailers and manufacturers.</p><p><b>  附錄B:</b></p><p><b>  低滾動阻力輪胎</b></p><p>  根據(jù)報告80%的或更多的汽車的燃料是由摩擦和其他類似的損失所消耗的。翻新輪胎具有較低滾動阻力可節(jié)省1.5%至4

46、.5%燃料。每年約2.37億美元的翻新輪胎在銷往美國。</p><p>  1. 美國的燃料使用、影響和機遇儲蓄</p><p>  美國的汽油使用對環(huán)境的影響是深遠的。擁有超過1.6億轎車和輕型卡車的道路上,每一年燃燒約126億加侖汽油。我們的燃料使用以約3%的速度繼續(xù)增長,在推動整體車輛數(shù)目持續(xù)增加和每輛汽車的平均距離上升帶動下,平均燃油經(jīng)濟性下降。</p><p&

47、gt;  今天,輕型車(汽車和輕型卡車)的約20%的氮氧化物,27%的揮發(fā)性有機化合物,一氧化碳的51%,大約30%的二氧化碳(主溫室氣體)全部是由全國人類活動排放的。不斷上漲的燃料的使用也有保護荒野和(容易增加探索)公共土地,水資源(油輪和管道事故),國家安全產(chǎn)生巨大影響。因此,機會節(jié)省資金,提高燃料的使用,通過減少環(huán)境質量是明確的。</p><p>  為橫跨整個車隊現(xiàn)有車輛節(jié)油最有希望的機會之一是利用而不是

48、標準低滾動阻力輪胎置換模式。這一變化提高了車輛的固有效率,自動節(jié)省了典型的3萬至5萬英里的一套輪胎壽命燃料。</p><p>  該報告審查了通過改進輪胎的節(jié)能技術的使用汽油的機會,特別是輪胎型號的建議而我們的初步測試數(shù)據(jù)表明,環(huán)境優(yōu)勢。其結果是適用于政府和企業(yè)車隊經(jīng)理以及個人輪胎買家。 </p><p>  2.輪胎如何能降低油耗</p><p>  據(jù)美國國家科

49、學院,約80%至88%在汽車的油箱的能源被浪費在各種熱,摩擦和備用的發(fā)動機和排氣系統(tǒng)損失。只留下約12%至20%轉換為實際車輛運動的勢能。減少車輛輪胎的滾動阻力是提高工作效率的主要途徑之一。這是不是一個輪胎的牽引或“握”在路面的措施,而是簡單地說明如何輕松地輪胎在道路上卷,盡量減少在輪胎側壁本身之間的輪胎與路面之間的輪胎和輪輞的熱量浪費的能源。 </p><p>  詳細的建模由國家可再生能源實驗室進行的結論是:

50、根據(jù)駕駛條件和車輛類型,在輪胎滾動阻力減少10%應產(chǎn)生約1%至2%的燃油節(jié)省。據(jù)在美國加州能源委員會的研究,如果使用的所有更換輪胎具有低1.5%至4.滾動阻力,約5%汽油的使用總量可節(jié)省。這相當于大約為平均節(jié)省高達30汽油每車每年節(jié)約,或由$ 2.5至750億美元的全國平均汽油節(jié)約價值加侖。 </p><p>  由于他們的努力,以滿足聯(lián)邦燃油經(jīng)濟性標準的一部分,汽車制造商通常指定其新車低滾動阻力輪胎。 1980

51、年至1994年,最低的滾動阻力輪胎型號實現(xiàn)了滾動阻力減少48%,并有可能以后繼續(xù)提高。這些原始設備(OE)的輪胎模型,偶爾會在替換輪胎市場,但往往只能通過特殊訂貨。一般來說,輪胎銷售給更換輪胎市場往往把對長壽和低價格更加重視,因此往往有較高的OE輪胎的滾動阻力比。 </p><p>  不幸的是兩個OE和更換輪胎的滾動阻力沒有任何標簽,目前,使車隊經(jīng)理和消費者愿意購買高能源效率的輪胎時,他們的第一套OE輪胎磨損已

52、經(jīng)陷入困境。即使輪胎制造商聲稱,特別是更換車型比其他人更好的燃油經(jīng)濟性,他們并不總是一致的測試方法或使用獨立的實驗室數(shù)據(jù)支持這些說法。每年,約2.37億沒有提供滾動阻力的標簽的更換輪胎銷往美國的汽車和輕型卡車。 </p><p>  2002年,能源基金會資助的ecos咨詢,分析輪胎市場,選擇滾動阻力測試代表車型,并與綠色標記的工作建議,表現(xiàn)良好的同時實現(xiàn)低滾動阻力特別車型。這些發(fā)現(xiàn)第一次被發(fā)表在此選擇綠色的報告

53、。的ecos咨詢的主要發(fā)現(xiàn)其他背景中可以找到為加州能源委員會編寫的另一份報告,在www.energy.ca.gov/reports/2003- 01 - 31_600 - 03 - 001CRVOL2.PDF可查。 </p><p>  3. 輪胎平衡性及其它注意事項</p><p>  輪胎的生產(chǎn),像其他工業(yè)生產(chǎn)過程,涉及重大的開采和生產(chǎn),以及能源消耗和各種污染物的排放。這些制造每個階段

54、以不同的方式影響環(huán)境。然而,輪胎,像其他消費產(chǎn)品的數(shù)量,實際上更多的環(huán)境影響在其使用和最終處置比他們負責制造。他們大大影響了車輛消耗的燃料量以它們所連接,導致全球變暖的排放以及當?shù)睾蛥^(qū)域空氣污染。他們創(chuàng)造微粒在穿著過程中的空氣污染,他們可以是一個重大的固體廢物問題,如果沒有妥善回收。 </p><p>  由意大利倍耐力輪胎制造商(圖1)所作的分析顯示,輪胎在整個生命周期能源消耗利用的主導地位。全生命周期的82%

55、來自能源使用輪胎的貢獻,汽車燃料使用時,大約18%相比,與獲得的原料和生產(chǎn)的輪胎本身相關聯(lián)。因此,輪胎的滾動阻力很可能是在其生命周期比它的組成,壽命長,最終的命運或環(huán)境影響較大的因素,雖然這些因素也值得考慮。 </p><p>  這份報告的地方測得的輪胎滾動阻力的輪胎之后的預期壽命和性能特征的考慮密切合作,最大的意義。一個具有高可導致滾動阻力的輪胎對環(huán)境的影響深遠,即使它干練扎道路和八點零零零萬英里持續(xù)。與此相

56、反,一個非常低滾動阻力輪胎可能不值得推薦,如果它的壽命是非常短或試驗數(shù)據(jù)表明,它提供了可憐的牽引力。 </p><p>  每一個輪胎目前市場上代表的期望之間的性能特點和價格各式各樣的平衡(我們調查的輪胎從25美元到200美元以上,每胎)。仔細地平衡這些特性不僅可以產(chǎn)生高效能的輪胎,而且是一個比目前市場上其他可用的環(huán)境更好。</p><p><b>  朗讀</b>&

57、lt;/p><p>  顯示對應的拉丁字符的拼音</p><p>  4. 輪胎滾動阻力評價和相關因素</p><p>  滾動阻力歷來是通過測量汽車工程師學會(SAE)的測試程序為J1269稱為官方社會。它需要推出措施以每小時50英里的速度對一個固定的測功機輪胎的力。一個新的程序,SAE的J2452,承諾改善評估在不同的速度滾動阻力的準確性,但目前沒有獨立的實驗室有能

58、力進行內(nèi)部這類測試。因此,我們進行的所有測試均在一個單一的符合SAE J1269標準的獨立實驗室。</p><p>  我們測試的最高和最低的滾動阻力在效率上相差60%,這表明輪胎的選擇有對燃油經(jīng)濟性有比大多數(shù)人意識到的更大的影響。 在類似的大小、類型和性能水平的輪胎中20%至30%的滾動阻力差距并不少見。這意味著如果配用合適的輪胎,為適度的低滾動阻力輪胎支付額外費,一輛私家車大約每年可節(jié)省燃料多達6%。換言之,

59、一個典型的如福特??怂剐⌒推嚳梢蕴岣咂鋸?0英里到32英里的里程只需使用低滾動阻力輪胎。對于一個平均每年節(jié)省約15000英里的汽車的燃料約50美元(每加侖1.50美元)。</p><p>  所有輪胎大小,類型,負載和速度等級都印在他們的側壁,如圖2所描述的信息。大多數(shù)型號的輪胎采用了“P”的客運車輛使用的名稱,但有些用“LT”的為輕型卡車使用的名稱。一般來說,“P”的輪胎似乎相對“LT”更受歡迎。</p

60、><p>  此外,美國運輸部要求各等級的輪胎制造商根據(jù)統(tǒng)一輪胎品質分級系(UTQGS),并為建立評級以下特點:胎面磨損,牽引和耐高溫性。不幸的是,每個輪胎型號公布的最終結果都比他們應該的要少。政府規(guī)定每個測試應該如何進行,并防止聲稱性能優(yōu)于衡量制造商。然而,它并不能阻止廠家聲稱比測量值差的性能。并且,奇怪的是,許多人,主要是為了擴大自己的輪胎營銷之間的區(qū)別在不同的價格點和鼓勵買家從一個“好” 移動到特定類別的“好”

61、或“最佳”的模式。</p><p>  由于收視率的變化及相關因素,我們已編制評估輪胎,包括聯(lián)邦額定值下文提到的和其他公布的我們自己的高性能復合指標各種數(shù)據(jù)。</p><p>  5.滾動阻力的未來發(fā)展</p><p>  努力在區(qū)分的基礎上更換輪胎滾動阻力仍處于非常初期的階段。如果沒有對整個的尺寸范圍內(nèi)的所有型號的輪胎滾動阻力的數(shù)據(jù),就不可能肯定本報告確定的模式是

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