The pros and cons of natural gas engines

Natural gas vehicles are changing the transportation industry, especially for fleet vehicles. Today there are more than 175,000 natural gas vehicles (NGVs) on the road and more than 23 million worldwide. A vast majority of these vehicles are heavy-duty, high mileage fleet vehicles designed for long-distance travel and hauling.

NGV vehicles have several advantages that make them attractive, especially as fleet vehicles. A few of these advantages include:

  • Natural gas fuel is more abundant and efficient: The US is the number one producer of natural gas in the world. We have over 90 years’ worth of supply, which gives natural gas greater price stability than gasoline or diesel. Natural gas is also more fuel-efficient than gasoline. It contains fewer hydrocarbons, and it has an octane rating of 130, which helps increase engine combustion and efficiency. It can be used in two forms in a natural gas engine: Compressed Natural Gas (CNG) or Liquefied Natural Gas (LNG).
  • NGV vehicles are better for the environment: Heavy-duty vehicles account for 50% of all smog emissions and 20% of all transportation-related greenhouse gases, despite only being 7% of the total traffic on the road. That’s a lot. Recent research from the University of California Riverside’s College of Engineering found that diesel engines emitted five times more NOx (nitrogen dioxide and nitric oxide) emissions than an NGV vehicle.
  • There are more NGV vehicles than you think. While it may be challenging to find a consumer NGV vehicle on the market, other industries have embraced NGV vehicles. Heavy-duty mileage trucks, transit vehicles, refuse trucks and school buses are some of the vehicles that now use natural gas engines. The heavy-duty trucking industry has especially embraced the NGV engines because of their lower fuel costs, improved fuel efficiency and reduced breakdowns. Fueling stations have expanded across the country, which makes it easier for large carriers to embrace the savings and efficiency of NGV vehicles. It’s also more accessible than ever to find the right NGV vehicles for your fleet. Fifty different US manufacturers are producing 100 different models of light, medium and heavy-duty vehicles.

The advantages of natural gas as a fuel source and vehicle speak for themselves. But what about the engines? How do natural gas engines produce such excellent fuel efficiency and savings? Here’s a quick breakdown of natural gas engines.

Natural gas engines operate very similarly to diesel and gasoline engines using a spark-ignited internal combustion engine. Fuel is stored in a tank, then injected into the engine where it is ignited by a spark plug system which causes the engine to run. There are also three different types of NGV engines:

  • Dedicated: Engines that run entirely on natural gas
  • Bi-fuel: Engines that can run on natural gas or gasoline with separate fuel systems
  • Dual-fuel: Engines that run on natural gas but use diesel fuel for ignition, usually found in heavy-duty vehicles

NGV engines that use CNG fuel tend to experience fewer breakdowns and lower maintenance costs over time. CNG fuel systems are sealed, so there is less chance of fuel loss or contamination. In the event of a spill, natural gas is less likely to ignite and mixes easily with air, so it disperses quickly in the environment. Combined with the fuel efficiency and savings that come with NGV engines, it’s no wonder that many fleet companies are beginning to embrace the technology.

However, like any new development, there are still drawbacks. Some of the issues still facing the widespread use of NGV vehicles include:

  • Fueling access: Compared to traditional fueling centers across the country, CNG and LNG fueling stations still have a long way to go. Currently, there are 1,680 CNG stations with another 50 planned, and 144 LNG stations with 38 planned. Here is an excellent map of the distribution of the stations, which clearly shows large areas where it may be difficult to fuel up.
  • Fuel storage: NGV vehicles require more space for storing fuel than gasoline or diesel-powered vehicles, especially when using CNG fuel. The cylinders to store the fuel may cut back on storage space in the vehicle. However, the fuel storage tanks are more durable to prevent spills and ruptures.
  • It is still an emerging technology. While NGV vehicles are increasing in popularity, especially in the heavy-duty transportation industry, they are still relatively unknown. Until there is widespread adoption, new engine developments and infrastructure to support NGV engines will take longer to accomplish.
  • Natural gas is not a renewable fuel. Despite the country’s abundant supply, and the reduced emissions that come with using natural gas, it is still a non-renewable fuel source. The US has over 90 years of natural gas reserves right now, assuming that consumption remains the same. If that number were to increase, the supply would dwindle faster, and prices may increase. The environmental impact of extracting natural gas is also high and can be a deterrent for increased adoption of natural gas as a fuel source.

NGV engines represent a significant change in the transportation industry. While NGV engines have not been heavily adopted at the consumer level, heavy-duty and high mileage transportation industries are excited about this technology and what it can do. The more we learn about NGV engines and develop the technology and infrastructure to support the industry, the bigger it will grow. Who knows how many vehicles will run on natural gas in the next few years? It’s certainly an exciting prospect that could help reduce emissions and protect our environment. As your fuel and lubricants supplier, we are here to help as new technology is continually developed to better meet your industry's needs.

Earn up to $1,500 cash back with Chevron’s Switch & Save promotion

Chevron’s popular Switch & Save New Account Rebate Promotion is back. This promotion offers a rebate of up to $1,500 to new-to-Chevron customers, for purchases of qualifying Chevron products, or to an existing customer for purchasing a new qualifying product. The premium lubrication products featured in this promotion can have a positive impact on your bottom line and the Chevron-supported Switch & Save rebates give you an incentive to purchase now!

The promotion will run June 8 – October 31, 2020.

Who is eligible to participate?

  • New customers who purchase qualifying Chevron products, as well as existing customers who upgrade or add a qualifying product that has not yet been purchased in 2020.
  • The purchase will have to be made between June 8th and October 31st.

How the promotion works?

  • Chevron will pay a rebate (by check payable) of up to $2/gallon to your new customers for every gallon of qualifying product they purchase during the promo period.
  • Some products will receive $1/gallon rebate and others will receive $2/gallon.
  • Customers can receive up to $1,500 (maximum rebate)!
  • There must be a minimum of 110 qualifying gallons per single invoice, but multiple invoices can be submitted.

Click here for complete promotion details including the qualifying products and rebate amounts per gallon. As your fuel and lubricants supplier, we encourage you to take advantage of this great promo!

How to interpret an oil analysis report

Oil analysis programs can save your business money. Regular testing of your oils and lubricants is an integral part of a proactive maintenance program that will help you identify contamination issues, reduce product waste and avoid costly equipment breakdowns and repairs. We are happy to provide our customers with this service through the Chevron LubeWatch Oil Analysis program and by working with Polaris Laboratories. Our customers have seen the results of enrolling in this program for their business.

If you’ve decided it’s time to start an oil analysis program at your company, that’s great. Getting started will take time to determine the best set up for your equipment and maintenance needs. We’ll help you determine a schedule for regular sampling and testing. Then you’ll receive a report full of recommendations for your business.
Understanding your oil analysis report is difficult. Nearly 32% of lubrication professionals do not know how to interpret an oil analysis report from a commercial laboratory, according to a recent poll from That’s a little disconcerting. If you’re going to invest in oil analysis, understanding your reports is crucial. Luckily we are here to help.

First, you need to understand what type of testing your samples will undergo. The most common parameters tested are:

  • Viscosity: Measuring the viscosity of your oil and lubricants is one of the first things you may notice in your report. Every lubricant is classified at a particular ISO viscosity grade (VG) to function correctly. If that reading has changed, your lubricant may cause overheating, wear and equipment breakdowns. If your results show that the viscosity grade of your lubricant has fallen within plus or minus 20% of the original grade, the lubricant will not work correctly.
  • Acid Number/Base Number: If you’ve forgotten high school chemistry, here’s a quick reminder. An acid is a substance that forms hydrogen ions. It’s corrosive and has a low ph value like vinegar. A base substance gives away hydrogen ions in solutions, and reacts with acids, like ammonia. In your oil analysis report, an acid number reading and base number reading indicate the level of acidic or basic properties the substance has. An acid number that is too high or low may indicate oil oxidation, an incorrect lubricant or additive depletion. Similarly, a base number that is too high or oil may indicate the presence of fuel, soot, the use of the wrong lubricant, leakage or oil oxidation. Both of these numbers can help pinpoint potential contamination issues or incorrect lubrication use.
  • Elemental analysis: Contamination issues are the reason many companies choose to pursue an oil analysis program. This testing checks for the presence of wear metals, contaminants or additive elements in the oil. Some of the tests performed may include Rotating Disc Electrode (RDE) and Inductively Coupled Plasma (ICP). These tests determine particle size, which is compared to previous tests to determine if contamination is occurring. Particle Counting is another test that accounts for the size and quantity of particles in the oil. There are several different methods to perform this test.
  • Moisture Analysis: Using a test known as the Karl Fischer titration test, moisture analysis measures any water present in three different forms: dissolved, emulsified and free. Results from this test help determine if there are potential leaks that may be contaminating your oil, internal condensation, temperature issues or seal leaks.

Now that you know what may be tested, it’s time to understand how it may look on your report. Each lab has a unique method of creating their reports, but universal principles remain. Most reports are broken down into sections such as these:

  • Information section: Your information, equipment information and type of lubricant being tested. This section is crucial and should always be checked first. It determines where the sample was pulled from, so if there are any issues, you know where to look.
  • Testing sections: These sections break down the variety of tests that were performed on the sample and the results. These tests are compared to previous results.
  • Results section: This portion of the report breaks down the overall results of your test. These results may be compared to the previous testing that was performed.
  • Recommendations section: Based on the findings of your testing, the lab will provide written instructions for how to best use the results of your analysis. This section is where the value of your oil analysis program becomes visible. Using these results, you can pinpoint potential maintenance issues before they become a significant problem.

If you are having trouble understanding your results and how to implement your recommendations, let us help. We are here to make sure that you get the best value out of the oil analysis program for your equipment. An oil analysis program is a significant investment. Still, it can pay off quickly for your business if you follow a careful monitoring schedule and the recommendations outlined in your report. Sign up for our oil analysis program today.