A newly released publication, “Renewable Natural Gas (RNG): The Solution to a Major Transportation Challenge,” reports that the use of renewable natural gas 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, and CALSTART, a California-based leader in clean transportation technologies.
“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. By aggressively embracing this strategy as part of an overall energy plan, the new Obama Administration and the 113th Congress can achieve measurable progress in moving toward this country’s key clean air, climate change, energy, national security, economic, and job creation goals. For many reasons, RNG is just what the doctor ordered.”
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.
- At the Fair Oaks Dairy in Indiana, biogases from liquid manure are harnessed into RNG 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 a day.
- 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/CALSTART 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.
Why Renewable Natural Gas? Why Now?
- Producing RNG fuel requires no drilling and avoids the environmental impacts of other fuel choices. Communities and companies need fuel for their essential bus and truck fleets, and the diesel fuel they have used for decades is now problematic. It is largely made from risky imported oil. It has volatile price swings, and diesel emissions have recently been labeled a “known carcinogen” by the World Health Organization. While fossil natural gas is a domestic resource, is 80% cleaner than diesel, and is 20%-25% lower in greenhouse gases, there is heated debate about the possible environmental and health impacts of obtaining this gas using the drilling technique known as horizontal hydraulic fracturing (or “fracking”). RNG, produced from waste, has no environmental downsides.
- Use of RNG can have a huge impact on U.S. security by significantly reducing our dependence on foreign oil: The 10 million diesel-powered buses and trucks for which natural gas engines are a fully commercial option deserve to be the priority target for RNG use. While they make up just 4% of all vehicles, they consume a whopping 23% of all vehicle fuel – 38 billion gallons a year. The recently released national Future Transportation Fuels Study commissioned by the Secretary of Energy, estimated that with today’s technologies, RNG could displace 16% of diesel vehicle fuel used annually or some 6.4 billion gallons; when “thermal gasification” technologies for processing tough woody materials (now on the horizon) become commercially viable, production of RNG could displace 45% of U.S. diesel consumption, some 17.9 billion gallons a year. State and federal incentives could greatly accelerate the pace of this shift.
- Using RNG as a vehicle fuel can strengthen the U.S. economy: Using domestically-produced RNG with today’s technologies can eliminate the need to send almost $18 million abroad each day ($6.4 billion a year) for diesel oil. In addition, according to a 2011 American Gas Foundation study, the scaling up of RNG production in the U.S. has the potential to create at least 250,000 sustainable energy jobs.
- RNG can help meet U.S. climate change goals: As measured on a life cycle basis, from production and transport to use of this fuel, RNG’s carbon footprint is reduced by 88% or more, as compared to pre-2009 gasoline and diesel vehicles, according to the California Air Resources Board.
- RNG also addresses this country’s expensive solid waste disposal challenge. The 28% of our municipal waste stream made up of food wastes and yard trimmings, (some 68 million metric tons a year) drains municipal budgets to collect and dispose of. However, it can be shipped off at lower cost if it is going to a site where it will be used as a feedstock for fuel production. In addition, the biosolids left after the gas is extracted from wastes processed in anaerobic digesters, can be recycled into fertilizers and soil amendments.
To read the Energy Vision’s report, visit http://energy-vision.org/wordpress/wp-content/uploads/2012/05/EV-RNG-Facts-and-Case-Studies.pdf