Inherent benefits of Allison's patented torque converter technology and full power shifts enhance the value of compressed natural gas (CNG)-powered trucks and buses. New customers around the world agree.
Allison Transmission has been a leader in developing fully automatic transmissions for commercial duty vehicles for more than 60 years, engineering products for gasoline, diesel and a growing number of CNG-powered commercial vehicle applications. Today, customers globally are adding CNG-powered trucks and buses to public transportation, environmental service, distribution, and construction fleets to meet the increasing global demand for affordable, clean, efficient, and quiet powertrains.
“An Allison automatic transmission is an enabler for use with CNG engines in several commercial vehicle applications,” said Lawrence A Love, executive director of Allison international marketing. “Unlike a diesel engine, CNG engines have different operating characteristics and are not as responsive during launch. Allison torque converter technology aids the CNG engine during vehicle start-up by multiplying engine torque and smoothly delivering power to the drive wheels. As a result, with an Allison, the vehicle gets good performance and makes the most efficient use of fuel.
“In addition, most CNG engines are not capable of using an exhaust brake or delivering the same level of engine braking capability as a diesel,” said Love. “However, the Allison transmission output retarder compensates for this by providing seamless auxiliary braking to improve overall vehicle braking capability and reduce service brake wear.”
The appeal of an alternative fuel source that burns 90% cleaner than diesel, and is also less costly, has convinced operators from Barcelona to Singapore in the past year to acquire Allison-equipped CNG vehicles. The inherent benefits of an Allison fully automatic transmission, including improved startability, more power to the wheels, and better engine response have caused them to specify Allison.
The Mercedes Benz Econic, on display recently in Allison's stand at the 2010 IAA show in Hannover, Germany, featured an alternative fuel engine combined with an Allison transmission. In the Netherlands, 30 Allison-equipped Econic CNG tractors have been purchased by Simon Loos, a large distribution company that delivers food to supermarkets around and in Amsterdam. These Econics comply with noise regulations, which allows them to operate in communities that otherwise could not be entered. Additionally, the Allison transmission makes the vehicles easy to drive in the heavy “stop and go” traffic in Amsterdam.
In Austria, Vienna Technical University, the Graz Energy Agency, Magna Steyr, and the shipping company Frikus have been testing a Mercedes Econic NGT as part of Magna Steyr's plant supply operations. The team is evaluating the amount by which a natural gas-driven Econic NGT reduces noise and emissions of carbon dioxide (CO2) and pollutants compared with a conventional diesel-powered truck. The Econic NGT 1828 semi-truck has not only cut noise by half, but it also reduced CO2 emissions by around 20% and nitrogen oxide emissions by about 30% versus diesel-powered vehicles. CO2 emissions were reduced thanks to the approximately 10% lower fuel consumption (26.5 kg of natural gas/100 km) compared with a diesel-powered truck.
In the past year, the city of Barcelona, Spain made a firm commitment to a sustainable future by launching into operation Spain's largest-ever order for CNG trucks. All of the 300 natural gas vehicles — including IVECO, Mercedes, Dennis Eagle, IPV, Urba I, and Urba II vehicles — are fitted with Allison transmissions and work for the environmental services department carrying out duties such as refuse collection and street cleaning. The public sector in Spain is increasingly opting for CNG vehicles due to their lower CO2 and nitrogen oxide emissions. Each of the four environmental service providers managing the city's requirements chose Allison to reduce operating costs, improve fuel consumption, and optimize service to the citizens of Barcelona.
In France, supermarket chain, Monoprix purchased 26 Renault and Stralis CNG trucks equipped with Allison automatic transmissions in a proactive move to cut pollution, increase productivity, and meet forthcoming emissions legislation (Euro 6 standards, 2012). For inner-city deliveries at all hours of the day and night, CNG power plus a fully automatic transmission makes for a quieter, cleaner truck.
Claude Samson, general director of Samada, the logistics arm of Monoprix, has witnessed significant improvements. “We have 85 stores in and around Paris that need frequent and reliable deliveries of products,” he said. “The Allison-equipped trucks outperform in terms of durability and efficiency.”
Eric Lamboley of Geodis Bourgey Montreuil (one of the transport partners) is equally satisfied. “CNG-powered vehicles have a lower engine torque compared to diesel powered trucks,” he said. “However, the Allison overcomes this challenge making the most of the power available. This is most apparent during acceleration from standstill — even on an incline.”
Earlier in 2010, Australia's first-ever order for a fleet of CNG refuse trucks — 23 Iveco 6×4 ACCOs complete with Allison 3500 Series transmissions — went into service. SITA Environmental Solutions (SITA), one of Australia's leading recycling and waste management companies, is one of a number of fleets in Australia testing CNG systems, reflecting a wider trend across a number of vocations within the country.
“Allison Transmission has actively responded to this trend by engineering and applying our conventional fully automatic transmissions into CNG engine equipped vehicles,” said Robert Cavagnino, Allison manager of sales and marketing for Australia and New Zealand. “We worked in conjunction with Iveco's team to review the engineering to ensure the engine characteristics were optimal, and it was determined optimum startability would be maximized through torque converter selection and the final drive ratios, which were altered to 6.83 to 1.”
China's CNG bus population is growing with approximately 2,500 Allison-equipped buses now serving Beijing, Shijiazhuang, Chongqing, Chengdu, Erdos, and Yinchuan. In Shijiazhuang, the number of express bus lines has expanded to include about 250 new CNG buses equipped with Allison transmissions.
For Yu Xinquan, the department head of technology and chief economist of the Shijiazhuang Public Transport Group, the transmissions had to be Allison. “Normally, the failure rate with a traditional city bus with a manual transmission is extremely high,” he said. “Products with lower quality require a repair every 20,000 kms or 50,000 to 60,000 kms at best for those with slightly better quality. The costs of replacement parts and maintenance, losses from a four-hour or even full-day suspension as well as the cost to provide spare vehicles are enormous. Thus, we must choose durable transmissions.”
Road testing has shown that the introduction of the new CNG buses with Allison automatic transmissions has almost halved fuel consumption.
In the United States, Allison has earned further significant new partnerships with OEMs to make its fully automatic transmissions available for a wide range of applications. Allison is facilitating the introduction of its transmissions to new CNG fleets across the nation. Freightliner Trucks has equipped its liquefied natural gas/compressed natural gas (LNG/CNG) Business Class M2-112 tractor, the LNG/CNG M2-112 straight truck, favored by municipal and other vocational applications, and its MT45/55 step van with Allison for delivery applications.
Kenworth Truck Company will offer a variety of Allison transmissions for use with the ISL-G engine, and in school buses, Blue Bird Corporation has equipped its large Type C conventional Vision school and activity buses using liquefied petroleum fuel with the Allison 2300 PTS model.
Allison continues to be specified by end-users in a variety of buses and trucks where there is the infrastructure to support them. New York City's sanitation department has recently ordered 10 trucks with 20 more on the way. At San Diego International Airport, Hertz Rental Bus has taken delivery of 17 CNG replacement buses — half of its bus fleet — using the B300 transmission. This is in line with the practice of many other fleets in California where incentive funding is accelerating the replacement of old vehicles with newer, lower-emitting diesel or natural gas alternatives. In the ports of Long Beach and Los Angeles alone, there are now more than 600 Allison-equipped clean air trucks.
Via McNeilus, the concrete truck producer, Allison has equipped 12 mixers to new customers in Oregon, Texas, and California in 2010. The Star concrete mixers are equipped with a Cummins CNG engine and the 4500RDS, a configuration used on McNeilus's demo truck with which it is targeting states with CNG infrastructure and an availability of regional, state, and federal clean energy technology assistance funds.
CNG in India was first introduced on Delhi's city buses in 1998, followed shortly by the conversion of all public city buses in Delhi from diesel to CNG. Since 2006, the urban modernization programs undertaken across India have resulted in orders for several thousand city buses. While almost 6,000 low-floor and semi-low-floor buses have been ordered in the past three years by 15 cities, almost 5,000 are CNG-powered city buses, which are serving the citizens of 10 cities in India.
While CNG is firmly established in some countries, others are beginning trials of the environmentally friendly technology. Sembcorp Industries, Singapore's largest waste management company, is starting a one-year field assessment of market acceptance, cost-effectiveness, and customer satisfaction using a Mercedes-Benz Econic. The vehicle is an Econic NGT 2628 6 × 2/4 NLA, with three axles and a gross vehicle weight of 26 tonnes, a trailing axle, and Allison transmission.
Russia is a growing market with the CNG bus population expanding in the cities of Moscow, Tol'yatti, and Yakutsk. Allison has been working closely with OEM Liaz, which produces CNG versions of its 12-meter, 12-meter semi-low floor, and 18-meter articulated buses. Of the more than 360 Allison-equipped CNG buses in operation in the country, 300 are in Tol'yatti — home to a large proportion of Russia's automotive production — alone.