Navistar, Inc. has signed a concept development agreement with UK-based Clean Air Power Ltd. to develop Navistar’s MaxxForce 13 big bore engine to run on natural gas and diesel fuel for the North American market.
The program will utilize Clean Air Power’s Dual-Fuel combustion technology (earlier post) to deliver a MaxxForce 13 Advanced EGR engine that is fully compliant with the US Environmental Protection Agency’s (EPA) 2010 on-highway diesel emissions, without the use of liquid-urea SCR (selective catalytic reduction). Upon successful concept development, the two companies will move forward to product development and validation.
Negotiations were underway for two years, according to Clean Air Power, during which time Navistar evaluated a number of different environmental technologies. Clean Air Power will spend approximately $1.5m on developing the concept over the next 10 months. During this time, in preparation for production and the next stage of development, Navistar and Clean Air Power will together seek US grant funding for full production.
As we assess changing market conditions, the ability to offer customers choice is important not only in our US markets, but in our global markets as well. As we develop this product for our International brand truck customers, we will also be able to leverage the technology in other markets and products as appropriate.—Eric Tech, president, Navistar Engine Group
MaxxForce 13 natural gas engines utilizing Clean Air Power’s Dual-Fuel combustion technology will initially target the regional haul tractor market with a goal of a achieving a 400-mile range.
Clean Air Power’s Dual-Fuel application enables diesel engines to operate primarily on up to 85-90% natural gas with diesel pilot ignition. The Dual-Fuel technology is fitted onto a standard diesel engine, enabling a measured quantity of natural gas to be mixed with the air just before it enters the cylinder and compressed to the same levels as the diesel engine to maintain efficiency. The Dual-Fuel engine uses a small injection of diesel fuel, around 10% of the total energy of the fuel, to ignite the main charge of gas and air.
Clean Air Power is developing a next-generation version of Dual-Fuel technology it calls MicroPilot. MicroPilot is based on the use of smaller diesel pilot injections representing 1-2% of the total fuel to reduce NOx emissions by more than 80%, while also reducing CO2 emissions.
The MicroPilot engine produces the low emissions characteristic of a spark-ignited lean-burn natural gas engine, but retaining the high efficiency and power density of a diesel engine. With recent advances in diesel fuel injection technology, the Directors of Clean Air Power believe that MicroPilot could be applied to heavy-duty engines within the 2010 deadline. Clean Air Power intends MicroPilot engines to be compliant with Euro V and beyond, taking the Dual-Fuel solution into the next decade.
In January, Volvo Powertrain signed a Letter of Intent with Clean Air Power Ltd. to incorporate Clean Air Power’s Dual-Fuel technology into Volvo Truck engines. (Earlier post.)