As we continue to explore the frontier of alternative fuels further, let’s shift our focus to another promising combustible option: compressed natural gas (CNG), a cleaner, more efficient energy source for our vehicles.

Over 175,000 vehicles already run on natural gas in the United States, contributing to a global tally of approximately 23 million. These are often work trucks or public buses. These natural gas vehicles (NGVs), particularly appealing for high-mileage fleets with central fueling, offer a viable fuel range within certain regions through compressed natural gas. For longer distances, liquefied natural gas (LNG) provides a higher energy density, aligning the fuel range more closely with conventional fuels.

Natural gas stands out for its domestic availability, extensive distribution network, and lower greenhouse gas emissions than traditional fuels when combusted. NGVs deliver performance on par with their gasoline or diesel counterparts, including horsepower and speed, while offering significant air quality benefits. Available from manufacturers or via aftermarket conversions, NGVs come in dedicated, bi-fuel, and dual-fuel configurations, catering to various needs and offering flexibility in fuel choice based on vehicle application and range requirements. Despite the lower energy density of natural gas, which may limit driving range, this can be mitigated by additional storage solutions; although modifications may affect cargo capacity.

While compressed natural gas offers a cleaner alternative to conventional fuels, it’s not without its challenges. The lower energy density of CNG leads to reduced driving ranges and necessitates larger storage tanks, which can compromise vehicle efficiency and cargo capacity. Furthermore, the existing CNG fueling infrastructure is limited, hindering broader adoption.

Additionally, CNG vehicles still emit CO2, albeit lower than their gasoline counterparts, but this remains a hindrance for those viewing climate change as a central concern and viewing the reduced emissions of natural gas as a half measure. Addressing these hurdles, research and development efforts are crucial. Engineers and scientists are tasked with innovating storage solutions to maximize energy density and minimize space, expanding the fueling network, and devising strategies to reduce CO2 emissions further. Advancements in these areas are key to enhancing CNG’s appeal as a sustainable fuel option.

Follow along in this alternative vehicle fuels series and click here for our kick off blog or the whole series.


Written by Mustafa Haque, Public Policy Intern

The Alliance for Innovation and Infrastructure (Aii) is an independent, national research and educational organization. An innovative think tank, Aii explores the intersection of economics, law, and public policy in the areas of climate, damage prevention, energy, infrastructure, innovation, technology, and transportation.