NGV Global’s Technical Chair, Dr Alex Lawson attended the ACT Expo in Long Beach, California last month and filed the following report:
For delegates attending the 2012 Alternative Clean Transportation Expo in Long Beach California, May 15 – 17, it became very evident that natural gas vehicles, especially in the heavy duty sector, had now become predominant compared with all other alternative clean transportation approaches.
All of the major truck manufacturers had LNG and CNG tractors on display – Daimler, Kenworth, Peterbuilt, Navistar, and Mack. Peterbuilt indicated that their natural gas vehicle production had increased from about 700 trucks in 2011 to over 2000 trucks in 2012 with an equal split between the ISL G 320 CNG and the GX 15 L LNG tractors. The reason for this growth is clear. The advent of shale gas with the decoupling of NG price from conventional oil, has resulted in a price spread from about $4 per gall for diesel vs just over $2 per DGE for LNG, that is LNG is about half the price of diesel.
An analysis of 5 year operating costs for a vehicle doing 600,000 miles at 6 mpg, was shown to have a total 5 year operating cost savings of $53,000, giving a payback of 3 years on the incremental cost of the vehicle.
The cost savings become even more dramatic with high mileage fleets. Love’s Truck Stops and Travel Stores reported that they have 280 locations throughout the USA. 300 refueling vehicles operated by Gemini Motor Transport haul 90% of the fuel delivered to Love’s fuel stations. These trucks burn 5 million gallons of diesel fuel per day and travel 30 million miles per year. Love’s has calculated that the savings resulting from converting all 300 fuel supply trucks to natural gas will pay for installing the natural gas refueling stations. This is a no risk scenario for Love’s. Natural gas refueling can then be offered to their customer base – either CNG of LNG – at little additional cost. This presents a great opportunity for cost effective expansion of natural gas fuel infrastructure in the USA. Clean Energy reported substantial expansion plans for LNG/CNG stations in partnership with Pilot Flying J truck stops, and by the end of 2012, it should be possible to drive an LNG truck coast to coast.
Encana is also expanding its LNG production capacity, and exhibited an LNG mobile refueller at the Expo. Mobile fuelling is designed to fill the gaps in existing infrastructure. Features such as built in spill containment facilitate permitting and collaboration with local fire marshals and building inspectors expedites site set up. Mobile fuellers can accommodate 40 – 100 LNG tractors; various proprietary features ensure long periods of storage, and pressure management allows delivery of any pressure required by the LNG vehicle.
In addition to infrastructure development, new heavy duty natural gas engines are also entering the marketplace to increase the range of availability for different truck applications. This includes the Cummins Westport 12 L NG engine which is spark ignition with TWC emissions control, which is creating a lot of interest. Cummins Engines also announced an even higher horsepower engine which is a 15 L spark ignited TWC equipped engine which offers an alternative to the current Westport Innovations 15 L HPDI diesel pilot NG engine. There is interest in the TWC spark ignited engines because they have simpler emission control systems than the diesel systems, and do not require the more complex urea DEF emissions control. The choice of engines will ultimately be dependent on the particular truck application and duty cycle. However, it is clear that the range of HD natural gas engines is considerably improving.
In use trucks are also being targeted for conversion to natural gas using dual-fuel diesel/NG systems. A number of aftermarket dual-fuel conversions were available including Ecodual, dHybrid, Green Pro Fuels, and American Power Group. The cost of the conversion can be less than $30K plus installation, so that payback periods of 1 – 2 years are feasible depending on the mileage of the vehicle. The dual-fuel systems typically average 70% substitution of natural gas, and are fully revertible to diesel when the natural gas fuel tank is empty. EPA compliance is relatively easy if the vehicle has reached its outside useful life of 435,000 miles. Certification of inside useful life engines are also planned. Omnitek offers conversion of diesel engines to spark ignited natural gas which is not unlike an engine overhaul. This involves changes to pistons, valves and valve seats, head modification to accommodate sparkplugs, a new engine management system and fuel storage tanks. 200,000 engines are overhauled each year, so this is considered a viable option to convert to lower cost natural gas given the relatively short payback period.
Considering megatrends and critical issues was the subject of the final panel discussion. Natural gas was considered the only long term alternative to conventional fuels, and there appears to be nothing on the horizon to stop it. Tank costs will likely be offset by less controls and simpler systems, so that the mature future NG truck is planned to have similar margins to that of diesel. There will be no difference in power or torque of the HD NG engine compared with diesel. There is considerable work involved in tank integration, changes to ECU systems, engine integration and range considerations, but the OEMs appear intent on getting it done. It was commented that the conversion of heavy duty gasoline engines to diesel in the past only took about 4 years, and that a similar trend is happening.
The final message related to heavy duty natural gas trucks was “Watch out for 2014”.
