Global Assessment of Hydrogen Technologies - Task 2 Report Comparison of Performance and Emissions from Near-Term Hydrogen Fueled Light Duty Vehicles

An investigation was conducted on the emissions and efficiency from hydrogen blended compressed natural gas (CNG) in light duty vehicles. The different blends used in this investigation were 0%, 15%, 30%, 50%, 80%, 95%, and ~100% hydrogen, the remainder being compressed natural gas. The blends were tested using a Ford F-150 and a Chevrolet Silverado truck supplied by Arizona Public Services. Tests on emissions were performed using four different driving condition tests. Previous investigation by Don Karner and James Frankfort on a similar Ford F-150 using a 30% hydrogen blend showed that there was substantial reduction when compared to gasoline in carbon monoxide (CO), nitrogen oxide (NOx), and carbon dioxide (CO2) emissions while the reduction in hydrocarbon (HC) emissions was minimal. This investigation was performed using different blends of CNG and hydrogen to evaluate the emissions reducing capabilities associated with the use of the different fuel blends. The results were then tested statistically to confirm or reject the hypotheses on the emission reduction capabilities. Statistically analysis was performed on the test results to determine whether hydrogen concentration in the HCNG had any effect on the emissions and the fuel efficiency. It was found that emissions from hydrogen blended compressed natural gas were a function of driving condition employed. Emissions were found to be dependent on the concentration of hydrogen in the compressed natural gas fuel blend