The main advantage provided by hydrogen fueled cars is a lowered dependence on fossil fuels. This can provide a number of environmental benefits as well as localized advantages to some countries. Since hydrogen fueled cars do not burn fossil fuels, limited resources can be redirected towards other uses. Widespread use of cars fueled by hydrogen can also result in less pollution, since these vehicles produce only heat and water as byproducts of operation. Countries that have a high reliance on foreign oil sources can also benefit from these vehicles because they potentially reduce foreign oil dependency.
Hydrogen is the most common element in the universe, and there are a variety of different ways it can be obtained. Most of the available hydrogen sources involve the element being tied up in more complex substances. Some of those sources, such as water, are in high abundance. Other hydrogen sources, such as natural gas, are nonrenewable resources. When hydrogen is extracted from nonrenewable resources, many of the potential advantages are more or less nullified.
The main challenge in realizing the full potential of hydrogen fueled cars is extracting the fuel source in a clean, renewable manner. In the same way that electric vehicles are a source of pollution if they are charged with electricity from a coal fired power plant, hydrogen that is extracted from that same electricity can also result in pollution. To be considered truly pollution free, the hydrogen needs to be extracted from sources other than natural gas, and the power used to perform the process should also renewable. If these goals are met, hydrogen fueled cars can provide a relatively clean, pollution free method of transportation.
Byproducts of the process that a hydrogen fuel cell uses to generate electricity typically are heat and water. This is unlike a gasoline powered internal combustion engine, which typically emits carbon dioxide, carbon monoxide, and a variety of particulates that can have adverse effects on the environment and human health. The difference in emissions between these two types of vehicles could result in benefits to both human health and the environment.
Some countries can also benefit from hydrogen fueled cars, in that this alternate fuel source could reduce their dependence on foreign oil. In this case, the source of the hydrogen and the electricity used to produce it may not matter as much as far as pollution is concerned. The more important factor is where the hydrogen comes from, since local sources within a country could allow that nation to import less fossil fuels.