Quantitative Risk Assessment Of Hydrogen Fuel Cell Buses

The energy shortage and environmental pollution worry the whole world due to the global economic development and the accelerating of industrialization.Hydrogen has attracted more and more attention due to the advantages of cleanliness and high efficiency.Hydrogen fuel cell vehicles have developed rapidly in recent years,including small family cars and large hydrogen fuel cell buses.The safety problems should be considered for hydrogen due to its high-pressure storage and flammability.Quantitative risk analysis of hydrogen accidents for specific scenarios will help the relevant safety standards development,the relevant facilities construction,and the emergency measure design.In this paper,the risks of fuel cell buses were quantified for different scenarios such as parking in garages,bus stations,and above-ground parking lots.The accident consequences and risks of hydrogen fuel cell buses were calculated using HyRAM software for various types of garages.The damage ranges of jet flame and explosion overpressures were calculated for high-and low-pressure pipe ruptures.The effect of garage size was analyzed.The potential loss of life（PLL）,fatal accident rate（FAR）,and average personal risk（AIR）were also calculated.The damage range of a high-pressure pipeline rupture was larger than that of a low-pressure pipeline rupture.The damage caused by explosion overpressure decreased with the garage occupation area.The potential loss of life,fatal accident rate and average personal risk of high-pressure pipeline rupture were higher than that of a low-pressure pipeline rupture.The quantitative risk assessment of hydrogen fuel cell buses was studied using DNV SAFETI software for parking lots and bus stops.The accident impact range and danger degree were analyzed for ruptures of the high-and low-pressure pipelines with different leakage rates.The explosion overpressure impact ranges for different wind speeds were compared.The results show that the explosion impact range resulting from a catastrophic rupture increased with the wind speed,while the explosion impact range of a pipeline leakage decreased with the wind speed.The regional personal risk and social risk were calculated for the accident scenarios of the parking lot and bus station.Both the personal risk and social risk were within the acceptable range.