美國聯合包裹服務公司，中文正式名稱為「優比速」公司，也就是全球知名的「UPS」快遞，22日宣布該公司已添購48輛以液化天然氣(LNG)為動力燃料的重型卡車，旗下的長程液化天然氣車隊因而到達59輛。
這批長程貨車將取代老一代的柴油車輛，減少UPS車隊廢氣排放，也邁向能源安全的目標。新車預計較舊型貨車少排放25%的溫室氣體，較汰換的車輛減少95%的柴油使用。
「這是重要的一步，不僅從環境角度來看，從美國能源安全的觀點亦然。」UPS車輛工程部門主任布里特(Mike Britt)表示：「液化天然氣是種較為便宜，燃燒時潔淨的燃料，對環境較為友善，比起傳統柴油更為永續。與此同時，這種燃料在美國境內有豐富供應量，不需要進口。」
液化天然氣，或液態甲烷，是將天然氣冷卻至攝氏負126度的低溫。在此溫度下，天然氣會成為液態，體積縮減615倍。
布里特說明，針對中、小型卡車動力燃料需求，已有多種技術與替代燃料正進行研發及推廣。「但目前，液化天然氣是唯一合適的替代柴油，適用於真正長程、重型聯結曳引車，就是你在高速公路上看到的那種。」
「液化天然氣的燃料特性是，其能源效益非常大，一定的容量便可提供大量的能源。使得液化天然氣成為絕佳的燃料，可供大型卡車補給燃料後長距離運輸。」
液化天然氣技術以天然氣作為主要燃料，在高壓下添加少量柴油至引擎燃燒室中。此類車輛製造商西港公司(Westport)估計，95%的柴油使用量可能天然氣所產生的能源所取代。美國能源部則估計其所替代的石油量，將達到每年125萬加侖。
UPS計劃在拉斯維加斯興建公眾可使用的液化天然氣加氣站，將可連結加州的安大略市(Ontario)與猶他州鹽湖城既有的加氣站，成為液化天然氣貨車運輸廊道，由加州延伸至猶他州。
布里特表示：「液化天然氣額外的優點是，它不會損害聯結車的性能，較為經濟，駕駛性能更佳，且大幅減少溫室氣體。」
這批卡車與加氣站是由加州南海岸空氣品質管理區與能源部的清淨城市計畫所資助。
UPS是唯一將液化天然氣技術使用在車隊的民營快遞公司，目前已有1100多輛以天然氣為動力的車輛投入服役。
除了液化天然氣，UPS已使用的替代燃料亦包括壓縮天然氣(CNG)，丙烷，與油電混合動力車，這些車輛服務的地點分布於美國、巴西、加拿大、法國、德國、香港和英國。
United Parcel Service, known around the world as UPS, has bought 48 heavy tractor trucks equipped to run on liquefied natural gas, bringing its long-haul LNG fleet to 59, the company announced today.
The long-haul trucks will replace older generation diesel vehicles, reducing emissions from the UPS truck fleet while heading toward energy security. They are expected to produce 25 percent fewer greenhouse gas emissions compared to the older trucks and use 95 percent less diesel fuel than the vehicles they replace.
"This is an important step not only from an environmental standpoint but from the viewpoint of U.S. energy security," said Mike Britt, UPS's director of vehicle engineering. "Liquefied natural gas is a cheaper, cleaner-burning fuel that is better for the environment and more sustainable than conventional diesel. And it's also a fuel that's in abundant supply inside the United States; it doesn't have to be imported."
Liquified natural gas, or liquid methane, is made by cooling natural gas to a cryogenic temperature of -126 degrees Celsius (-260 degrees Fahrenheit). At that temperature, natural gas becomes a liquid and its volume is reduced 615 times.
Britt says multiple technologies and alternative fuels being explored or deployed to provide propulsion for smaller and mid-sized trucks. "But at the moment, LNG is the only suitable alternative to diesel for the really heavy, long-haul tractor trailers you see on the highway."
"As a fuel, LNG is very dense, providing a large amount of energy for the amount of space it occupies. This makes LNG an excellent potential fuel for large trucks that need to travel a long distance before refueling," he said.
LNG technology uses natural gas as the main fuel with a small amount of diesel delivered at high pressure to the combustion chamber. Westport estimates that 95 percent of the diesel fuel usage is replaced by energy generated from the natural gas. The U.S. Department of Energy estimates this displacement will amount to about 1.25 million gallons of petroleum annually.
UPS plans to build publicly accessible LNG fuel stations in Las Vegas and will be able to access existing fuel stations in Ontario, California, and Salt Lake City, Utah, filling in an LNG trucking corridor that extends from California to Utah.
"The added advantage of LNG is it does not compromise the tractor's abilities, fuel economy or drivability, and significantly reduces greenhouse gases," said Britt.
Funding for the trucks and fueling stations is supported by California's South Coast Air Quality Management District and the Energy Department's Clean Cities program.
UPS is the only private delivery company using this LNG technology in its fleet and now has more than 1,100 natural gas-powered vehicles in service.
Besides liquified natural gas, UPS has deployed compressed natural gas, propane, electric and hybrid electric vehicles in the United States, Brazil, Canada, France, Germany, Hong Kong and the United Kingdom.
全文及圖片詳見：ENS報導
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In my healing journey and learning to attain the breath awareness, I become aware of the reality that all the creatures of the world are breathing the same breath. Take action, here and now. From my physical being to the every corner of this out of balance's planet.
