PART II of II
Why Natural Gas?
- Natural gas is a proven technology that is cost-competitive and reduces both criterion air pollutants and GHG emissions.
- CNG and RNG are well-suited for use in congested areas where human health is compromised due to poor air quality. This is because CNG and RNG reduce criterion air pollutants, such as NOx and particulate, by 90% over the cleanest Diesel engines.
- As such, CNG and RNG offer cost-competitive and commercially-ready technology that benefit human health and combat the effects of climate change.
What is Renewable Natural Gas?
Both Conventional Natural Gas and Renewable Natural Gas (RNG) contain an identical CH4 molecule. RNG is a green fuel that comes from waste material, such as garbage, human waste, and animal manure. As such, RNG uses waste streams that are part of the current lifecycle to create a useful product that burns cleanly and significantly reduces Greenhouse Gas emissions as compared with gasoline or Diesel.
| GHG reductions accrue when using CNG and RNG as opposed to gasoline or Diesel | |
| Conventional (fossil) Natural Gas (CNG) | 5% – 15% |
| Renewable Natural Gas (RNG) sourced from a landfill | 40% – 50% |
| RNG sourced from a municipal wastewater treatment plant | 75% – 85% |
| RNG generated from animal manure | 100% |
With the above context in mind, we would do well to be thoughtful when making transportation-fuel choices moving forward. Just as “Silver Bullet” isn’t the best beverage for all occasions, there is no single silver bullet that will ween us off of Diesel and gasoline. Renewable propane may be a good choice for First Responders, where rapid acceleration is important. Battery-electric technology is almost certainly the right choice for passenger cars and light-duty vehicles, but battery-electric technology has proven both expensive and unreliable in medium- and heavy-duty applications. . While the notion of steam as exhaust is extremely compelling, hydrogen-fuel technology is not ready for commercial deployment, and this fuel type is not readily available. We have yet to identify a solution for long-haul, heavy-duty trucking with inconsistent routes and multiple destinations. We do know, however, that RNG, with CNG as back-up fuel, works very well for fleets that return to base on a regular basis. That’s why you can’t find a transit bus, a refuse truck, or a drayage vehicle in Southern California that isn’t already burning RNG. To that end, let’s pursue an “all-of-the-above” strategy that embraces the best technology for each application.