|Tata 5L engine with GEMdi. Click to enlarge.|
Westport Innovations Inc. unveiled its newest proprietary dual-fuel technology: Westport gas enhanced methane diesel (Westport GEMDi), applied to Tata Motors’ new 5-liter dual-fuel methane-diesel engine. Westport GEMDi technology enables engine original equipment manufacturers (OEMs) to offer a fully integrated, high performance engine optimized for dual fuel operation.
Westport co-developed GEMDi technology with Tata Motors on the next-generation 5L engine, targeting medium-duty trucks and buses in India. This technology provides fuel flexibility, beneficial in regions where natural gas infrastructure is emerging, such as India, and is designed to meet Euro IV and V emissions standards.
A dual fuel engine typically relies on conventional diesel engine hardware, modified to allow operation with natural gas fuel. Under dual fuel operation, natural gas is introduced at low pressure and mixed with the intake air. Diesel fuel is introduced directly into the combustion chamber near the end of compression stroke and is used to ignite a lean mixture of natural gas and air (i.e. no spark plugs are required).
Since dual fuel engines are closely configured based on a diesel engine, it allows them to provide higher performance (torque and power) and efficiency on natural gas fuel as compared to a traditional spark ignited natural gas engine. Based on Westport analysis, typically a dual fuel vehicle would operate at about 60% average fuel substitution ratio (i.e. fraction of total fuel energy contributed by natural gas), with the remaining coming from diesel fuel. Higher fuel substitution ratios are possible through improved engine design and control. Dual fuel engines are capable of reverting back to 100% diesel operation over the entire engine operating range if required.
The base diesel engine with Westport GEMDi is optimized for dual fuel operation through fuel and combustion system modification and advanced engine monitoring and control. In a typical aftermarket retrofit, the dual fuel operation may not be fully optimized. Westport proprietary natural gas components will be integrated directly into OEMs’ operations, providing OEMs with the highest quality standards and reliability to customers.
Tata’s 5L natural gas engine featuring Westport GEMDi was displayed at India’s Auto Expo in New Delhi; upon successful completion of the development phase, commercialization with Tata Motors is expected to follow, with Westport supplying key natural gas engine components.
India is one of the world’s largest truck and bus markets. Its total annual medium- and heavy-duty truck and bus sales are projected to reach over 289,000 units in 2014 and 478,000 units in 2022, according to the Natural Gas Trucks and Buses report published by Navigant Research at the end of 2013. Tata’s 5L engine with Westport GEMDi technology is primarily targeted for medium-duty trucks and buses running on dedicated routes in India.
According to Navigant Research and Westport analysis, India’s medium-duty natural gas truck and bus population is projected to be over 12,000 units in 2014, representing a 5% market penetration, and is expected to quickly grow to more than 60,000 units in 2022, reaching a 15% market penetration in the medium- and heavy-duty truck and bus market.
|New Tata 3.8L turbo gas SI engine. Click to enlarge.|
Tata 3.8L natural gas engine. Westport Innovations and Tata Motors also launched a new spark-ignited (SI) natural gas 3.8L turbocharged engine featuring the Westport WP580 Engine Management System (EMS). Designed to support many engine configurations, the Westport WP580 EMS is also scheduled to be applied to Tata’s 5.7L engine targeting medium-duty applications in late 2014.
The Westport WP580 EMS is a highly configurable system that has been specifically developed for spark ignited, dedicated natural gas engine applications and can be integrated with a wide range of proprietary Westport fuel system components for flexible vehicle design and production. Its advanced combustion control technology can optimize the engine for fuel economy, torque, and power while meeting existing and future emissions and onboard diagnostic requirements. Westport has also set a new benchmark with the WP580, with industry leading price performance and value, allowing natural gas vehicles to be competitively priced with petroleum-based vehicles.
The Westport WP580 EMS is specifically tailored to maximize the performance of the base engine. Key benefits include reduced fuel consumption and emissions, increased vehicle load carrying capabilities with launch torque, and integrated vehicle functionality.
The system is designed to meet Euro VI emission standards. Tata’s SI natural gas 3.8L turbocharged engine featuring the Westport WP580 EMS was also displayed at Auto Expo.