The lack of infrastructure for transporting and dispensing renewable fuels to end-users is a significant barrier that will need to be addressed if renewable transportation fuels and advanced vehicle technology are to penetrate the current market. However, there are several pilot projects that have been introduced that are paving the way for making this transition to cleaner transportation practices
The National Aeronautics and Space Administration (NASA) recently released a press release stating that it is working on a prototype for a commercial hydrogen fueling station that uses wind and solar powered-energy to perform electrolysis to produce hydrogen. The first plant is slated to be built in the Cleveland area next to the Great Lakes Science Center and will use water from Lake Erie. It will utilize wind and solar power from existing facilities at the science center.  The first objective of the project is to create a commercial scale hydrogen refueling station that generated hydrogen on-site through electrolysis that is powered by clean energy sources. The second is to build the plant with commercially available parts so that other stations may follow. The third is create an exhibit that publicizes the refueling station’s purpose and merit by taking advantage of its location at the Great Lakes Science Center.
This hydrogen refueling station is not the first commercial-scale clean technology refueling station. In Frankfurt, Germany, a new electric vehicle battery recharging station has been built in order to charge the city’s small scale electric vehicles (EV).  The station, fueled by panels provided by Evergreen Solar, supply free recharging to vehicles such as Velotaxis, Segways, electric bikes and scooters to promote the use of low-emission vehicles in this high-traffic area.  The station located in a major commercial shopping center, allows consumers to charge their cars at one of its six charging ports while they shop, since this type of refueling takes much longer than traditional gasoline and diesel fuel refueling.  The station is projected to produce approximately 21 kWh of electricity on peak days.  To provide a sense of scale, this is the amount of electricity that could fuel an electric scooter to travel about 71,500 miles a year. The cost of the stations was approximately $85,100 (USD). 
Pilot projects such as the refueling station in Cleveland, OH, and Frankfurt, Germany are paving the way for the transition to cleaner forms of transportation. Although they represent nascent attempts to penetrate the current transportation fueling system, they are integral in engaging the scientific and clean-tech community, as well as public interest.
1. Owens, J.P., NASA Leads Team in Establishing a Renewable Hydrogen Fueling Station in NASA's Glenn Research Center-Press Release. 2009: Cleveland, OH.
2. Press, A., Evergreen Solar PV Panels Power EV Recharging Station in Germany, in RenewableEnergyWorld.com. 2009: Massachusetts.