There has been a lot of talk lately about making changes in our energy systems. Fossil fuels are facing a number of challenges including rising costs and their inevitable release of carbon dioxide into the atmosphere. Current climatic studies reflect a mounting destabilization of our weather patterns and a general rise in average global temperatures. The rising costs of fossil fuels and concerns about global climate change are powerful motivators for a search for alternatives.

Renewable energy sources such as wind and solar will likely play important roles in our expanding energy base. However, these sources have limitations. Specifically, there are major obstacles in their use for transportation. Current electric vehicles are expensive and, due to the inefficiency of the batteries, have limited range and power. Great hopes have been placed on the emergence of fuel cells as an energy source for electric vehicles. A number of different approaches are being developed but a primary source of energy “fuel” for these fuel cells is hydrogen.

Hydrogen is a very abundant element throughout the universe. On planet Earth, hydrogen is most commonly found in water, with our oceans making up the largest reserves. Hydrogen is relatively easily split from water through electrolysis. A flow of electrical current is required for this process. The source of this electricity can be traditional nuclear and fossilfueled power plants; the electricity can also be obtained from renewable sources of energy, such as solar and wind power. Wind farms in the prairie states could provide the electricity needed to create hydrogen though electrolysis, for example. Solar arrays along coastlines could be used to separate the hydrogen and oxygen molecules in ocean water. Hydrogen can be easily transported, either through pipelines or tanker rail cars, to its point of use. This kind of scenario might allow for the rise in use of hydrogen as a fuel for transportation in fuel cell powered vehicles. However, there are a number of challenges facing the widespread implementation of fuel cell powered vehicles.

First, it is very difficult to store and contain hydrogen safely and effectively. Hydrogen is an extremely lightweight element and is a diffuse gas at ambient temperatures and pressures. It would take a very large volume fuel tank to replace a typical gasoline tank while providing a comparable range of driving. Another major problem facing the introduction of hydrogen powered fuel cell vehicles is the relative unavailability of hydrogen as a fuel. It is likely that a significant supply and demand problem lies ahead. Until fuel cell powered cars are common on the road, it is unlikely that hydrogen will be readily available at filling stations. And unless a consistent and reasonably priced supply of hydrogen is available, it seems unlikely that there will be much of a market for fuel cell powered vehicles.

A potential solution to this conundrum may exist as nearby as your local auto repair shop. It turns out that with a modest number of modifications, gaseous hydrogen can be burned as a fuel in existing internal combustion vehicles. (Hydrogen combusted in the presence of oxygen produces energy and water as its exhaust. It is an extremely clean-burning fuel.) One possible strategy would be to produce duel-fueled vehicles that could run on both gasoline and hydrogen, switching between fuels as needed. With the ability to switch from one fuel source to another, a greater security in fueling can be provided. These duel-fueled vehicles could provide a “bridge” strategy for the transition between a carbon based energy source and a hydrogen based energy source, long before fuel cell powered vehicles become cost effective and thus prevalent.

Currently, the Dartmouth Organic Farm is proposing an innovative research and demonstration project to explore the feasibility of such a vehicle. Should adequate funding become available, a group of students would design and convert an existing gasoline-powered internal combustion engine pick-up truck into a duel-fueled hydrogen/gasoline vehicle for farm use. This project would create an innovative and practical application of hydrogen fuel that would provide outreach and educational value while providing transportation for the farm program. It would represent a small, simple step towards a future powered by hydrogen.

Scott Stokoe is the advisor for The Green Magazine as well as the full time head of the Dartmouth Organic Farm.