在2016年SAE International商用車輛工程大會首日舉辦的“應(yīng)對（中、重型商用車的）第二階段溫室氣體排放挑戰(zhàn)：影響與效果”研討會上，廣大專家、學(xué)者及從業(yè)人員相聚一堂，共同探討如何應(yīng)對相關(guān)挑戰(zhàn)。當(dāng)日，美國環(huán)保署交通運輸與空氣質(zhì)量辦公室主任ChristopherGrundler發(fā)表主題演講，為大會拉開帷幕。在演講中，Grundler強調(diào)了實施排放法規(guī)對控制排放的重要作用，比如最近發(fā)布的第二階段溫室氣體排放標(biāo)準（影響范圍為2021-2027型號年的中/重載公路車型）。
“我們必須加快推進我們的計劃，現(xiàn)在真的是在與時間賽跑。”他在提到全球氣候變化時表示，“我們正在進入一個未知的領(lǐng)域，”目前大氣中的CO2水平首次超過400ppm。
根據(jù)美國環(huán)保署和國家公路交通安全管理局（NHTSA）的預(yù)計，整個項目可以減排超過10億噸CO2、節(jié)約20億桶原油，并同時為車主節(jié)約1700億美元的燃料費用。
對于本身就在監(jiān)管范圍內(nèi)的7級和8級聯(lián)合拖拉機而言，與第一階段標(biāo)準相比，完全生效后的第二階段標(biāo)準最高可降低25%的CO2排放和燃料消耗；對于第二階段剛剛納入監(jiān)管范圍的重載聯(lián)合拖拉機拖車而言，新標(biāo)準在完全生效后預(yù)計可以使2017款拖車最高減排9%。
環(huán)保署與安全局稱第二階段為“技術(shù)進步”階段，需要目前尚未廣泛應(yīng)用的新興技術(shù)積極投入使用，發(fā)揮作用。不過，Grundler很快指出，新標(biāo)準為“技術(shù)中立”，并不傾向于某項具體技術(shù)。
“我們的工作不僅僅是制定標(biāo)準，然后拿出一些數(shù)字，”Grundler說，“如果使用這些卡車的用戶不愿大量購買新技術(shù)，那我們就失敗了。”
主題演講后，4位行業(yè)專家也就這一主題發(fā)表了各自的觀點。來自全美卡車制造商協(xié)會（Truck Manufacturers Association）的Timothy Blubaugh再次重申了其他幾位發(fā)言人在大會上的發(fā)言，表示必須建立一套全國性的標(biāo)準，方便廠商制造可直接面向全美各州的標(biāo)準車型和發(fā)動機。
“為了保證全美50個州的同步參與，加州必須采用第二階段標(biāo)準。”Blubaugh表示，“我們聽到一些聲音說，CARB認為某些不在美國監(jiān)管范圍之內(nèi)的特種車輛可以享有一些靈活度。因此，我們有點擔(dān)心，因為我們必須保證一致性，這至關(guān)重要。”
北美貨運效率委員會（North American Council for Freight Efficiency，NACFE）Dave Schaller一直在協(xié)助車隊了解各種技術(shù)，包括一些可以提高能效的技術(shù)，以及那些可能在特定應(yīng)用情況下并不非常有效的應(yīng)用。
Schaller表示，“怎樣才能讓車隊對這些技術(shù)有信心，愿意為其付費，這是一個問題，因為他們有很多選擇的機會。”他指出，NACFE的網(wǎng)站上已經(jīng)測評了大約70種適用于8級長途和區(qū)域貨車的新技術(shù)。
現(xiàn)在看來，技術(shù)實施的五大障礙分別為回報時間不確定、可靠性存疑、資金來源缺乏、可靠信息不足以及可用技術(shù)缺乏。
Schaller與其在NACFE的同事Michael Roeth在SAE所發(fā)表的技術(shù)論文（2016-01-8014）中描述了車隊面臨的困難，“對于車隊而言，這些技術(shù)可能很難為他們帶來真正收益。輕量化技術(shù)可以方便一些對關(guān)注重量的車隊運營，但對于其他所有車隊而言，這種技術(shù)很難真正提高車隊的回報。”這只是他們在論文中的一個例子。
Schaller和Roeth還指出，SAE和技術(shù)與維護委員會（Technology & Maintenance Council）等支持性組織應(yīng)盡快起草必要標(biāo)準與措施，支持行業(yè)盡快開發(fā)采用節(jié)油技術(shù)。
西維吉尼亞大學(xué)的Nigel Clark表示，隨著我們收集的數(shù)據(jù)越來越多，以及對負載和天氣等參數(shù)的理解越來越深刻，未來我們的道路統(tǒng)計數(shù)據(jù)庫也將越來越龐大，并發(fā)揮更大作用，這可以幫助我們了解真實世界的情況。目前，Clark正在西弗吉尼亞大學(xué)的替代燃料、發(fā)動機與排放研究中心（WVU Center for Alternative Fuels, Engines and Emissions）開展相關(guān)研究。
“道路統(tǒng)計數(shù)據(jù)庫將有助于推動設(shè)計和認證方面的發(fā)展，”他說，“我們必須在更多了解同一類車輛在不同行業(yè)和負載之下的情況?，F(xiàn)在，大量的信息均留在車隊內(nèi)部了。”
Clark著重介紹了一系列有助于提高燃油效率的“工具箱中的工具”，并指出另外一些可能帶來挑戰(zhàn)的技術(shù)，比如余熱回收系統(tǒng)。
“如果你選擇利用廢熱，這項技術(shù)可能會花你很多錢，”他說，“利用余熱的方式有很多種，但經(jīng)濟性并不高，而且這還會增加車輛的重量。因此，我們在使用余熱時必須提前進行很多測評，這只是一個例子。”
AVL公司的Lukas Walter認為，只要進行進一步的開發(fā)和優(yōu)化，行業(yè)“絕對可以”憑借現(xiàn)有技術(shù)實現(xiàn)即將生效的第二階段標(biāo)準。他認為，商用車領(lǐng)域應(yīng)當(dāng)尋找與其他行業(yè)共用零部件的機會，從而優(yōu)化電池等技術(shù)的商業(yè)效益。
有沒有一種技術(shù)可以將CO2排放降低20%以上？Walter在會上提出這個問題，并稱替代能源可能是一種答案。舉例來說，AVL的測試結(jié)果顯示，與柴油發(fā)動機相比，在同等扭矩水平下，天然氣直噴系統(tǒng)的排放量要低20%以上。
Walter表示，“二氧化碳的減排要求將推動替代能源的未來發(fā)展。”
Opening day of the SAE 2016 Commercial Vehicle Engineering Congress featured a well-attended symposium on Meeting the Challenges of Phase 2 GHG: Implications and Effects. A keynote presentation by Christopher Grundler, Director of the Office of Transportation and Air Quality for the U.S. EPA, kicked off the event, during which he stressed the importance of implementing emissions regulations like the recently issued final Phase 2 greenhouse gas standards affecting model year 2021-2027 medium- and heavy-duty on-highway vehicles.
“We need to accelerate what we’re doing because we really are in a race against time,” he said regarding global climate change. “We are heading now into uncharted territory,” with average CO2 levels in the atmosphere exceeding 400 parts per million for the first time ever.
The U.S. EPA and National Highway Traffic Safety Administration (NHTSA) expect the new rules to save more than 1 billion metric tons of CO2 emissions and 2 billion barrels of oil, while also saving vehicle owners $170 billion in fuel costs, over the life of the program.
For Class 7 and 8 combination tractors—one of four regulatory categories—the fully phased-in standards will achieve up to 25% lower CO2 emissions and fuel consumption compared to the Phase 1 standards. Trailers used with heavy-duty combination tractors, a new category for Phase 2, are expected to achieve an up-to-9% reduction compared to an average model year 2017 trailer once the standards are fully phased in.
The agencies refer to Phase 2 as a “technology-advancing” phase that will require emerging technologies not yet in widespread use. Grundler is quick to note, however, that the standard is “technology neutral.”
“Our job is more than just setting standards and having some numbers,” Grundler said. “If the people that use these trucks don’t buy them in numbers that matter, we’ve failed.”
Following the keynote, four SAE-member industry experts provided their respective viewpoints on the topic. Timothy Blubaugh of the Truck Manufacturers Associationechoed what several other speakers stated at COMVEC—that there needs to be one nationwide standard that allows manufacturers to build a single fleet of vehicles and engines for the U.S. market.
“California must adopt [Phase 2] as is to keep a 50-state program,” he said. “We’ve heard noise that [CARB] thinks there should be aerodynamics on certain vocational vehicles where it’s not required in the U.S. rules [for example]. So we’re a little concerned, but it’s a critical element of ensuring that we have [consistency].”
Dave Schaller of the North American Council for Freight Efficiency (NACFE) works with fleets to help them understand the technologies that improve fuel efficiency, and those that aren’t as effective in certain applications.
“How do fleets gain the confidence to go out and spend the money. There are so many opportunities for them,” Schaller said. Around 70 adoptable technologies for the Class 8 line-haul and regional-haul industry are evaluated on the NACFE website, he noted.
Five major barriers to adoption are uncertain payback time, questionable reliability, lack of access to capital, a dearth of credible information, and lack of technology availability.
Illustrating the struggles fleets face, Schaller and his NACFE colleague Michael Roeth write in SAE technical paper 2016-01-8014, “There are areas that can be hard to monetize. Lightweighting benefits are easy for weight-sensitive fleet operations, but to all other fleets, the value of running lighter is much more difficult to factor into the payback calculation.” This is one of many examples they detail in the paper.
Schaller and Roeth also note that support organizations such as SAE International and the Technology & Maintenance Council should be quick to develop the needed standards and practices to support the industry in its efforts to develop and quickly implement fuel-saving technologies.
On-road statistical databases that reflect real-world use are going to grow and have greater impact as better data is gathered and more is known about factors such as loads and the weather, according to Nigel Clark of West Virginia University. Clark conducts research within the WVU Center for Alternative Fuels, Engines and Emissions.
“On-road statistical databases are going to drive design and certification changes,” he said. “We’ve got to know more about different vocations and loads within a class. Right now, a lot of this information is held by fleets.”
Clark highlighted a number of “tools in the toolbox” to help improve fuel efficiency, pointing out those that pose some challenges such as waste heat recovery.
“When you come to use that waste heat, the technology can be quite expensive,” he said. “You can use it in various ways, but it isn’t economical and it also adds weight to the vehicle. So that’s an example of one that requires quite a lot of examination.”
Lukas Walter of AVL believes the industry “can definitely achieve” upcoming legislation like Phase 2 with already-demonstrated technologies that just need further development and optimization. The commercial vehicle sector should examine other industries for component-sharing opportunities to improve the business case of technologies such as battery systems, he said.
Is there a single technology that can reduce CO2 by more than 20%? Walter posed this question and offered alternative fuels as a possible solution. Natural gas direct injection, for example, could achieve more than 20% reduction at the same torque level as a diesel engine, according to AVL testing.
“CO2 reduction is the future driver for alternative fuels,” he said.
Author: Ryan Gehm
Source: SAE Truck & Off-highway Engineering Magazine
伊頓汽車集團的Mihai Dorobantu（左一）擔(dān)任本場嘉賓討論主持人，其他嘉賓包括：卡車制造商協(xié)會的Timothy Blubagh、北美貨運效率委員會的David Schaller、西維吉尼亞大學(xué)的Nigel Clark，以及AVL集團公司的Lukas Walter（從左到右）。
美國環(huán)保署交通運輸與空氣質(zhì)量辦公室主任Christopher Grundler表示，在應(yīng)對氣候變化方面，“我們真的是在與時間賽跑?！?。
全美卡車制造商協(xié)會（Truck Manufacturers Association）Timothy Blubaugh
NACFE的David Shcaller指出，SAE等支持性組織應(yīng)盡快起草必要標(biāo)準與措施，支持行業(yè)工作的推進。
西維吉尼亞大學(xué)的Nigel Clark表示，“建立道路統(tǒng)計數(shù)據(jù)庫，將有助于推動設(shè)計和認證方面的發(fā)展?！?/span>
AVL集團公司的LukasWalter表示，“二氧化碳的減排要求將推動替代能源的未來發(fā)展?！?/span>