ECOtality North America
ECOtality North America provides technical support and field services for all aspects of electric vehicle infrastructure
Chevrolet Silverado/GMC Sierra HICE ConversionECOtality North America/Roush Hydrogen ICE Silverado Truck
Of the first 9 HICE Silverados in production, eight will participate in the "Integrated Wasted Hydrogen Utilization Project (IWHUP)" a 3-year, 18 million dollar (Cdn) initiative sponsored by several departments of the provincial and Canadian federal government. The HICE Silverado has excellent performance and versatility with 195 Hp / 265ft.lbs of torque, 6-passenger capability and a range of 210 miles (EPA Highway driving schedule). Although more advancements and refinements are always desired, the performance and emission results of the current HICE Silverado are very encouraging. Delivery of the first few HICE Silverados has begun and customer feedback has been extremely positive.
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In addition to engine control, the OEM PCM also controlled transmission operation and provided vital information for the proper operation of the instrument cluster. Two prototype vehicles were constructed to allow for in-vehicle calibration of the powertrain (engine and transmission) Final engine and transmission calibration was performed in various regions around the country to ensure that the HICE engine performs as it should in various climates and elevations. These regions included Detroit Michigan, Phoenix Arizona and Flagstaff Arizona (higher elevation). A subcontractor was enlisted to reverse-engineer the J1850 messaging for this vehicle. With this information, software was written for the new PCM to allow for proper communication to other vehicle control systems and to ensure proper operation of accessories such as the air conditioning system.
Summary of final engine and transmission calibration:
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The HICE Silverado is an OEM-quality conversion of a Chevrolet Silverado/GMC Sierra 1500HD Pickup Truck modified to operate the GM Vortec 6.0 Liter V8 gasoline engine on 100% hydrogen fuel. The fuel system was designed by Powertech Labs to the latest existing and proposed standards. Engine calibration and vehicle integration services were performed by Roush Industries utilizing their state-of-the-art engine dynamometer facility and experienced engine calibration and vehicle integration professionals.
| Vehicle Range | 237 km (147 miles) City 339 km (210 miles) Highway |
| Horsepower | 146kW (195 hp) |
| Torque | 352Nm (260 lbs-ft.) |
| Top Speed | 161 km/hr (100 m/hr) (Est.) |
| Fuel Economy | 22.5 km/kg (14 mpg) City 32.3 km/kg (20 mpg) Highway1 |
| Weight | 2864 kg (6300 lbs.) Curb Weight 3909 kg (8600 lbs.) GVWR |
Standard Features:
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Vehicle Modifications (Engine and Fuel System):
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Emissions TestingIn July of 2006, emissions tests were conducted at Argonne National Labs. These tests were conducted as part of the ECOtality North America/ETA contract with the US Department of Energy (DOE) Advanced Vehicle Testing Activity (AVTA). The truck tested in July was a 2005 Chevrolet Silverado 1500 HD. For this round of testing, ANL & ECOtality North America conducted a full coastdown test to determine the actual road loads for this vehicle in this configuration. The only coastdown data available from the US Environmental Protection Agency is for a generic Silverado pickup truck equipped with a four-wheel-drive system. We felt that this configuration would lead to additional parasitic losses and, thus, adversely affect the emissions results for the HICE trucks which are rear-drive only. As part of the coastdown test, a more representative test weight was determined following the guidelines of SAE J1263 (resulting in a slightly higher test weight than was used originally by the manufacturer for EPA testing). Additionally, this second emissions test event benefited from additional engine calibration work.
Table 1 presents the results of FTP testing: Table 1: FTP Emissions Results
Table 2 presents results for the HWY FET tests. Table 2: HWY FET Emissions Results
All values are g/mi with the exception of Fuel Economy (mi/kg). In June, 2005, this same truck was tested in its original gasoline configuration after accumulating 7000 miles of typical driving. These tests were conducted at Roush Industries' vehicle emissions facilities using state-of-the-art equipment. As a coastdown test had not been conducted on this vehicle at the time, the coastdown coefficients and test weight used for the dynamometer were selected from the 2005 EPA test results for a Silverado pickup truck. The test weight used was 5250 lb, quite a bit lower than the 6300 lb used for the HICE testing conducted in June, 2006 (see above). As a result, one would expect these values to be optimistic (i.e., lower) for a vehicle with a delivered curb weight near 6000 lb. The results of those tests are presented here for comparison. Table 3 presents results for the FTP tests. Table 3: FTP Gasoline Emissions Results
Table 4 presents results for the HWYFET tests. Table 4: HWYFET Gasoline Emissions Results
All values are g/mi with the exception of Fuel Economy (mi/gal).
US EPA Certification Standards for Light-Duty Gasoline Vehicles (Tier II, Bin 8):
Note that the original gasoline engine as delivered from the manufacturer is rated in the Heavy-Duty category. As such, different, less stringent, emissions standards would have applied to this vehicle. However, it is worth noting that the HICE conversion is capable of meeting (and exceeding) the more stringent standards. Furthermore, it is worth while to compare the HICE measured emissions values to those specified by Vancouver's AirCare program:
With these comparison values, it can be seen that the HICE configuration emits less NOx on a g/mi basis than the actual measured amounts for the FTP gasoline test as well as the allowable standard amounts for both the US EPA and Vancouver's AirCare program. For the HWYFET test, the results for the HICE configuration is nearly equivalent to the gasoline measured results and is below the values allowed by US EPA and Vancouver's AirCare program. The US DOE recently awarded ECOtality North America a contract to perform testing and monitoring to determine the durability of HICE systems. Included in this project will be regular emissions test which will shed light on the ability of these vehicles to maintain low NOx values as they accumulate mileage. |
Contact information:
Kevin Morrow
Phone: 602-716-9576 x 24
Email: kmorrow@etecevs.com
2 Fuel economy is calculated using a hydrogen mass flow meter, total miles driven during each of the three phases, and a standard calculation for weighting the results for the three phases
3 NOx values not available due to instrument error
The HICE Silverado is an OEM-quality conversion of the 1500HD vehicle platform utilizing the Vortec 6.0 Liter V8 engine. For this development effort, ECOtality North America partnered with other experts in the automotive and gas systems field. Roush Industries is a major automotive engineering and low-volume manufacturing company that services automotive OEM's and Tier One Suppliers in all areas of automotive engineering, development and testing. Powertech Labs is a wholly owned subsidiary of BC Hydro operating 18 Labs at its Surrey BC facility with approximately 80 professional engineers, scientists and technologists and is world-renowned in hydrogen storage component and systems design, testing and certification. With the expertise of ECOtality North America, Roush and Powertech, the HICE Silverado is built to the latest standards (both established CNG standards and those in draft form for hydrogen) and to the highest quality.
Although HICE technology is not considered as technically advanced as fuel cells by some, a significant amount of research and development effort was required to achieve the desired performance and tailpipe emissions goals. Integration with the existing GM platform includes replacement of the original GM Powertrain Control Module (PCM) to provide the flexibility required for proper engine calibration, instrumentation and vehicle systems operation and control for the automatic transmission to properly operate with the power curve of the HICE engine.
The ninth truck will participate in the DOE Advanced Vehicle Testing Activity (AVTA) under the FreedomCAR and Vehicle Technologies Program which will perform vehicle durability and performance tests and publish the results on the AVTA website.
HICE Silverado Development Background
Gaseous fuel injectors designed for use with Hydrogen are installed on the engine using custom fuel rails with fuel temperature and pressure sensors. Additional engine modifications include the integration of an OEM electronic throttle and replacement of the standard spark plugs with custom plugs designed to operate in the Hydrogen fuel environment.
In order to calibrate the engine and transmission properly, the original Powertrain Control Module had to be replaced with an appropriate aftermarket PCM. The HICE modified engine was then installed on one of Roush's engine dynamometers for proper engine mapping and calibration (shown in the accompanying pictures). A significant amount of time and cost in labor hours setting up and operating the engine dyno for the HICE engine and the hydrogen fuel during the testing was expended, but this activity is an absolute requirement to properly map and calibrate the HICE engine. The PCM employed for this conversion allows for sophisticated math modeling of engine processes which result in precise control of air/fuel ratios as well as typical cold-start, engine accessory and transient issues.
These test results show some amount of CO2 which is unexpected for hydrogen combustion. Engineers at Argonne National Labs continue to look into this issue. There is a theory that a nearby building that is testing large locomotive engines may be providing a source of intermittent elevated CO2 levels that are not properly accounted for in regular background level measurements.
It may also be beneficial to compare the most recent HICE emissions numbers to the US EPA certification levels (standards) for model years 2005 and 2006 light duty vehicles. As NOx is the only pollutant of concern with the HICE configuration (given that THC, CO, and CO2 theoretical and measured values are extremely low), only the EPA certification levels for NOx are presented.