A newly released publication, Renewable Natural Gas (RNG): The Solution to a Major Transportation Challenge, reports that the use of renewable natural gas (biomethane) as a vehicle fuel is a technologically viable alternative to relying exclusively on petroleum-based fuels for transportation. The new publication was prepared by Energy Vision, a national, New York-based energy research organization.
“Today we can turn this country’s expensive organic waste burden into a clean vehicle fuel solution,” said Energy Vision President Joanna Underwood. “Waste biogases can also be used to generate power and heat homes; but other renewable energy sources can meet those needs. Fossil-based and renewable natural gas used as vehicle fuels are the only options for displacing significant amounts of oil.”
Underwood’s panaceac enthusiasm for biomethane is tangible, describing it as having the capacity to meet key US clean air, climate change, energy, national security, economic and job creation goals.
For example, according to California ARB’s Low Carbon Fuel Standard analysis, CNG or LNG from conventional fuel pathways provides full fuel cycle GHG reductions of 12% to 28% in comparison with diesel fuel. By comparison, CNG or LNG from renewable fuel pathways provides full fuel cycle GHG reductions of 70 to 88% vs. diesel fuel.
RNG is made from organic wastes discarded by homes, industries and agricultural operations. Deposited in oxygen-free environments including landfills or specially built tanks called anaerobic digesters, these organics decompose and emit biogases that can be collected and refined into a fuel similar to fossil natural gas. RNG can be blended with fossil natural gas or it can replace it.
The eight RNG projects cited in the report show what can be done on this “green fuel” frontier. Three examples:
- At the Fair Oaks Dairy in Indiana, biogases from liquid manure are harnessed into biomethane fuel equal to 1.5 million diesel gallons a year, which is used to power 42 large tanker trucks hauling Fair Oaks’ milk to Michigan, Kentucky and Tennessee. Estimated fuel cost savings from this fuel switch total more than $2.5 million a year.
- At a large California landfill owned by Waste Management, biogases from decomposing wastes are refined by Linde N.A. into a clean fuel equal to 13,500 diesel gallons a day which is trucked to refueling stations where it powers almost 400 refuse trucks.
- In St. Landry Parish, Louisiana, the community just opened a fueling station to supply 15 municipal vehicles with clean landfill-derived RNG fuel. The waste from 40,000 households is estimated to be able to power up to 50 vehicles, and the costs of the system will be fully recouped in four to five years.
Underwood said, “Communities of 40,000 or more may generate enough organics to produce fuel for their bus and truck fleets and more. But smaller communities, which have neighboring towns and nearby dairies, hotels, food processing plants or other organic waste sources, should begin to join together and explore pooling their wastes and investing in production of the fuel.
The Energy Vision report summarizes nine major obstacles to communities and companies that want to produce RNG for vehicle fuel. These range from the up-front costs of constructing anaerobic digesters in which the biogases from wastes form, and installing the technology needed to refine these biogases, to existing standards that make it difficult to transport RNG through natural gas pipelines and provisions in the U.S. Tax Code rewarding production of biogas for power generation but not for vehicle fuel.
(This article compiled using information from an Energy Vision press release)
