Pathways for natural gas into advanced vehicles:Part A: technology and fuels for new generation vehicles

We are entering an era when vehicle technology is going to be diversified. We are facing developments that include improved internal combustion engines, hybrid power trains and fuel cell vehicles, and the fuel spectrum is predicted to grow broader. Energy security, diversification of sources and sustainability are issues discussed as they relate to various fuel alternatives.With today's knowledge, the first fuel cell vehicles will be equipped with PEM fuel cell stacks that operate on hydrogen. Hydrogen can be generated either outside the vehicle or on-board the vehicle. There are several fuel options competing to be the preferred fuel for fuel cell vehicles: sulphur-free gasoline type hydrocarbons, methanol and hydrogen - either gaseous or liquid.It will take years for FC vehicles to really penetrate the market. Meanwhile, we will still be running vehicles equipped with internal combustion engines. Emissions have to be controlled, and therefore practically sulphur-free fuels will be needed. Here the use of natural gas will make a strong point, both regarding possibilities for emission reductions and energy diversification. Thus natural gas has found its way, for example, into the transportation energy scenarios of the European Commission for the year2020.Natural gas will also play a significant role in supplying energy to fuel cell vehicles. Today, the greater part of hydrogen for industrial purposes is produced from natural gas by steam reforming. For energy purposes, hydrogen could be produced from natural gas in both centralised and decentralised systems. Centralised production would even make it possible to remove CO2 by sequestration. It is doubtful with today's technology if it is possible to combine natural gas storage on-board the vehicle with on-board reforming for fuel cell vehicles due to weight and space constraints. If it were possible, it would be a tremendous opportunity to utilise the existing CNG or LNG refuelling network.This report or "Position Paper", which has been prepared within the IANGV Technical Committee, is a status report on vehicle propulsion and fuel technologies. It strives to answer the question as to how natural gas can make a contribution to fuelling the vehicles of the future.The report, which was completed in April 2002, covers, among other things, advances in engine, propulsion and fuel technologies, fuel options, fuel cell technology, hydrogen production and handling and system level efficiencies and emissions. The newest data in the report dates from February 2002. Development in the fuel cell sector is so fast that some information becomes outdated very rapidly. The report does not deal with economic aspects of different fuel and propulsion options.