Here is a quiz for sustainability executives. How can you save money while reducing greenhouse gas (GHG) emissions by over 20%? The answer: run your transportation fleet on CNG or LNG fuel. Companies with private fleets and contracted fleets can enjoy the savings of CNG and LNG while doing their part for sustainability and environmental stewardship.

Studies conducted by the California Air Resources Board (CARB), and other experts, have documented the substantial GHG reductions possible through using natural gas as a vehicle fuel. These studies examined the "well-to-wheels" carbon footprint of various fuels. Well-to-wheels is a life cycle assessment that looks at how a fuel is produced, processed, transported, distributed, and consumed. Rather than just examining tailpipe emissions, well-to-wheels studies look at the full emissions picture.

CNG and LNG, from domestic natural gas, reduce GHG emissions by almost 30% as shown in the chart below, with CNG showing greater reductions than LNG because of the amount of energy used in the production of LNG.

Even more remarkable than domestic natural gas are the reductions possible with Renewable Natural Gas (RNG), also known as Biogas and Bio-methane. RNG is virtually carbon neutral, with reductions approaching 90%! RNG is naturally produced at landfills, dairy farms, sewage treatment plants and biogas production plants. Clean Energy operates an RNG production facility at a large landfill near Dallas, where we extract decomposition gases through a collection system. The natural gas is then purified until it meets the pipeline distribution system's quality standards. We produce over 35,000 equivalent gallons of low-carbon gas per day at this one landfill, which is then transported to nominated consumption locations.

A fleet can use a mix of domestic natural gas and RNG to achieve a specific carbon reduction target. Imagine using a mix that achieves a 30%, 40%, 50% or even greater reduction of GHG emissions. Major refuse companies, such as Republic Industries and Waste Management, have publicly announced their plans to harness their landfills for this low carbon vehicle fuel. Dairy farms are also jumping on the RNG bandwagon. I've been told that a dairy cow's manure can produce as much as a half gallon per day of fuel. Now that is potent stuff!