Compressed Natural Gas (CNG) & Renewable Natural Gas (RNG/R-CNG)
CNG is produced by compressing natural gas to less than 1% of its volume at standard atmospheric pressure. To provide adequate driving range, CNG is stored onboard a vehicle in a compressed gaseous state at a pressure of up to 3,600 pounds per square inch.
CNG is used in light-, medium-, and heavy-duty applications. A CNG-powered vehicle gets about the same fuel economy as a conventional gasoline vehicle on a GGE basis. One GGE equals about 5.66 pounds of CNG.
Renewable Natural Gas (RNG/R-CNG)
Renewable natural gas (RNG) is produced from feedstocks including animal waste, crops and crop residue, and food waste.
RNG, or biomethane, is a pipeline-quality gas that is fully interchangeable with conventional natural gas and thus can be used in natural gas vehicles. The use of RNG in the form of compressed natural gas (R-CNG) can reduce lifecycle greenhouse gas emissions compared to fossil fuels. Encouraged by government policies, demand for RNG is increasing in multiple sectors.
Liquified Natural Gas (LNG)
LNG is natural gas in its liquid form. LNG is produced by purifying natural gas and super-cooling it to -260°F to turn it into a liquid. During the process known as liquefaction, natural gas is cooled below its boiling point, removing most of the extraneous compounds found in the fuel. The remaining natural gas is primarily methane with small amounts of other hydrocarbons.
Because of LNG's relatively high production cost, as well as the need to store it in expensive cryogenic tanks, the fuel's use in commercial applications has been limited. LNG must be kept at cold temperatures and is stored in double-walled, vacuum-insulated pressure vessels. LNG is suitable for trucks that require longer ranges because liquid is denser than gas and, therefore, more energy can be stored by volume. LNG is typically used in medium- and heavy-duty vehicles. One DGE equals about 1.7 gallons of LNG.
Liquified Renewable Natural Gas (BioLNG)
BioLNG is derived from renewable resources, such as organic waste, not from fossil resources, making it a 100% biofuel. That is why BioLNG makes it possible to reduce CO2 emissions in the short term with chemical properties practically identical to that of liquified natural gas (LNG).
Key Benefits of Using Natural Gas Fuels
The use of RNG in natural gas-fueled vehicles, either as renewable compressed natural gas (R-CNG) or liquefied renewable natural gas (BioLNG), offers customers already using these vehicles an attractive alternative for lowering their carbon footprint and meeting their sustainability goals. BioLNG can reduce lifecycle emissions by as much as 80-95% compared to conventional fuels, depending on the fuel source and production pathway.
LNG can help reduce the “well-to-wheel” greenhouse gas emissions from heavy-duty trucks by up to 22% compared to conventional diesel today, with further reductions possible in the future.*
Vehicles fueled by LNG provide equivalent driving range, engine power and performance to diesel-fueled heavy-duty vehicles.
Engine noise reduction
Using LNG can help reduce engine noise by up to 50% when compared to heavy-duty diesel engines, contributing to improved driver wellbeing and vehicle use in noise abatement zones.**
By using LNG and BioLNG as their fuel of choice, drivers are actively contributing to decarbonization–and can benefit from new skill sets associated with LNG fueling practices.
LNG offers a cost-competitive solution with a higher energy density.
When managed properly, LNG and BioLNG do not pose any greater risks than other fuels that are regularly loaded and transported by heavy-duty vehicles.
* “Well-to-wheel” greenhouse gas emission reductions are based on current ISO 9001 standards for analysis and EPA & GREET emissions values. “Greenhouse gas emissions” includes CO2, methane, and N2O.
**A truck running on an LNG gas engine will produce noise levels at 72dB(A), equal to a normal car. An average diesel-powered truck will produce 82 dB(A). To give in idea of how significant that reduction is: every 3dB(A) reduction in noise halves the intensity of the sound (because sound is scientifically measured on a logarithmic scale).