While many of you are familiar with the use of biogas as a means for powering or heating our homes and businesses, I believe that the use of biogas as a transportation fuel is the least well-known and understood application for this versatile and greenhouse gas reducing resource. For this reason, my previous columns have focused on the vast potential of biogas as fuel for our vehicles. If this potential is to be reached, however, a critical component of the plan needs to be addressed first: infrastructure.
While current biogas projects can clean and compress biogas into a usable vehicle fuel, new infrastructure is needed to distribute the fuel to our vehicles. Fortunately, the infrastructure needed to use biogas as transportation fuel is enabled by the large infrastructure build out already occurring for compressed natural gas (CNG). Since biogas can be cleaned to a form that is a direct replacement for conventional natural gas (referred to as biomethane), new fueling pumps and compression equipment capable of filling up CNG vehicles can also dispense blended or pure biomethane. Increasing the amount of biomethane in the overall system not only provides a domestic transportation fuel option, but also decarbonizes the natural gas distribution system, similar to how integration of renewable electricity in the transmission system decarbonizes the electricity grid.
In late August, a new biogas fueling station opened at the Rodefeld Landfill in Madison, Wis. The fuel coming out of the nozzle at the bio-CNG filling station will come from biogas collected at the landfill. Dane County had already initiated the process of converting its county fleet vehicles to run on natural gas instead of diesel fuel, which has displaced 25,000 gallons of diesel/gasoline and saved Dane County taxpayers an estimated $50,000 annually. Dane County taxpayers will see even greater savings with lower natural gas purchases. Currently, natural gas prices are forecast to remain low, but combining biomethane with conventional natural gas purchases provides an important hedge in the event natural gas prices spike. Wisconsin joins the ranks of states that have installed dedicated fueling infrastructure for biogas, including Indiana, Ohio, Texas and Pennsylvania.
The blending of biomethane with conventional natural gas is also being pursued by Clean Renewable Fuels. Currently, the majority of gasoline dispensed in the U.S. is a blend of 90 percent gasoline and 10 percent ethanol. This concept can be applied to CNG fueling. Clean Energy Renewable Fuels has developed RNG-10 and RNG-20 to market an even cleaner and low-carbon option to customers, and continues to build out natural gas fueling infrastructure. As the infrastructure improves, we will see a significant increase in vehicles filling up with a mix of conventional natural gas and biomethane.
While progress is being made in the U.S., Sweden provides a great illustration of what the future could look like. Nearly half of the vehicles—not just passenger—designed to run on natural gas are fueled by biomethane. Sweden harnesses biogas from wastewater treatment facilities, agriculture byproducts, household organics and food processing waste to fuel taxis, trains, buses and large fleet vehicles. The country has built an impressive biomethane distribution system to fuel all these vehicles.
Many exciting developments are occurring in our transportation system, and the build out for natural gas refueling infrastructure will bolster increased use of biogas to help meet our transportation needs. Although it is encouraging to see new infrastructure construction, like the bio-CNG fueling station in Wisconsin, there is much more that could be done to fully capture the vast biogas opportunity.
Author’s note: This column first appeared in the October 2013 edition of Biomass Magazine.