RNG from Waste (the Next Gold Rush?)

November 1, 2018

Americans are wasteful. As a nation, our disposable mindset leads to more than 300 million tons of trash being sent to landfills each year. And the problem is only getting worse, as trash production in the United States has almost tripled since 1960.

Some of the top waste collection companies in the country have taken note of this unsettling trend, and have set out to pioneer innovation that would mitigate our population’s impact on the environment while making our air cleaner to breathe. Two of these leaders are Waste Management (WM) and CR&R Environmental Services (CR&R), which operate large fleets of heavy-duty waste collection trucks. Recently, both companies have been steadily replacing their diesel fleets with trucks equipped with near-zero-emission engines that run on renewable natural gas (RNG) that they produce from the waste they collect each day.

More than 300 million tons of trash is being sent to U.S. landfills each year, emitting harmful methane emissions.

How is RNG Produced?

When food and green waste begins to decompose and breakdown in landfills, it emits harmful methane emissions that contribute to climate change. When the methane is instead captured and refined, it can be converted to ultra-clean and ultra-low-carbon natural gas that can be used to fuel vehicles—as WM and CR&R are doing—or injected into utility natural gas pipelines to provide heat and power to homes and businesses. RNG provides an abundant source of renewable energy and can offset society’s use of fossil natural gas that is extracted from the ground.

What is a Near-Zero-Emission Engine?

In 2014, Cummins Westport received certification from the California Air Resources Board and the U.S. Environmental Protection Agency for a natural engine that has emissions so low, they are practically undetectable (0.02 g/bhp-hr NOx). WM and CR&R became two of the first companies in the nation to deploy trucks with these near-zero-emission natural gas engines. Amazingly, when they fuel their trucks with RNG, these engines emit levels of smog-forming pollutants so low that they are four to nine times cleaner than electric trucks of comparable size charged by power from the California grid. One almost wonders why these renewably powered engines aren’t called sub-zero-emission vehicles when zero-emission tailpipe vehicles are still treated as if their emissions were truly zero or fossil-free?

Innovative waste collection companies are capturing the methane emissions and refining the methane to produce renewable natural gas (RNG).

Waste Management’s Journey to Clean Vehicles

Waste Management (WM) operates the largest vocational heavy-duty fleet in North America, with more than 6,800 of its trucks operating on natural gas, making it the largest heavy-duty natural gas truck fleet of its kind in North America. For every diesel truck they replace with natural gas, they reduce their use of diesel fuel by an average of 8,000 gallons per year, along with a reduction of 14 metric tons of GHG emissions. About 30 percent of WM collection trucks are natural gas vehicles (NGVs), with plans going forward to increase NGV purchases to approximately 80 percent of the fleet. They have CNG fueling capabilities at over 100 of their facilities, as well as 25 public fueling stations.

WM has been a pioneer in natural gas since the early 1990s and has invested more than $1 billion in low-emission vehicles and fueling infrastructure. Across the country WM has invested in state-of-the-art technology to produce RNG from waste. In total, 16 million diesel equivalent gallons of RNG are produced by harnessing the methane in company landfills. WM uses the RNG to fuel its fleet, lowering fuel costs and reducing GHG emissions by more than 80 percent compared to trucks powered by diesel.

Waste Management has invested in state-of-the-art technology to produce RNG from waste, using RNG to fuel its fleet.

CR&R’s Unique Approach to Waste Utilization

CR&R is a forward-thinking waste and recycling collection company that services more than 2.5 million customers throughout Southern California. The company operates one of the cleanest and most advanced fueling operations of any refuse fleet in the nation. CR&R was another early adopter of NGVs, having deployed its first CNG collection truck in 2002. Today there are more than 400 natural gas trucks operating in their waste and recycling collection fleet of approximately 1,000 vehicles. The company is set on converting 100% of their vehicles to run on natural gas.

CR&R is helping California cities and businesses meet their waste diversion goals and mitigate harmful methane emissions from decomposing organic waste by operating a state-of-the-art high solid anaerobic digester (HSAD) in Perris, California. The HSAD has the capacity to convert 335,000 tons of organic waste that would have otherwise been deposited into landfills into ultra-low-carbon RNG. Besides fueling their fleet with RNG, CR&R spearheaded a landmark project, becoming the first digester operator in California to inject RNG into the Southern California Gas Co. (SoCalGas) natural gas distribution system. Once the HSAD facility is fully complete, it will be able to produce 4 million gallons of RNG annually.

CR&R operates a high solid anaerobic digester, producing RNG to fuel their trucks and inject into the natural gas distribution system.

The HSAD facility was funded in partnership with the California Energy Commission, CalRecycle, and the South Coast Air Quality Management District (SCAQMD). CR&R secured further funding through the SCAQMD’s Prop 1B Goods Movement Emission Reduction Program to help offset the incremental costs of natural gas vehicles.

Building Upon WM and CR&R’s Success

Each of us can help innovative companies like WM and CR&R by cutting down on the amount of waste we throw away (reduce, reuse, recycle!). But even with robust waste diversion programs, our society will continue to produce waste. Given our current climate circumstances, capturing climate-altering methane emissions from our waste stream should no longer be treated as an optional solution. Utilizing RNG at scale is a cost-effective solution to power all strategies that California and climate-thinking states want to implement.

RNG provides an abundant source of renewable energy and can offset society’s use of fossil natural gas that is extracted from the ground.

In California, funding opportunities such as those listed above, coupled with the Greenhouse Gas Reduction Fund (GGRF), support a wide range of programs and projects to reduce GHG emissions, thereby providing economic, environmental and public health benefits, while reducing our dependence on fossil fuels. Across the U.S., states should prioritize funding to develop more projects that divert organic waste from rapidly filling landfills, as well as to encourage the purchase of NGVs that will consume the RNG produced by these projects. WM and CR&R are leading by example, helping waste collection fleets understand that what their companies are doing can be replicated, in turn helping the country understand how critical it is to sustainably manage municipal refuse in order to reduce GHGs and decarbonize the energy supply.