Natural gas engines vs. diesel engines

Natural gas fueling station

From tractor trailers and transit buses to delivery trucks and terminal tractors, fleets have traditionally relied on diesel engines to provide the torque, reliability and durability needed by heavy-duty commercial applications. Natural gas engines, however, have emerged as a great alternative to diesel. Drivers, mechanics, and fleet managers appreciate natural gas engines for a variety of reasons.

Drivers find that natural gas engines have similar performance and drivability as diesel engines. The leading difference between natural gas and diesel engines is noise; natural gas engines are quieter.

Natural gas offers convenient refueling options

Natural gas also improves the refueling experience for many fleet drivers. In a world of several alternative fuel options for commercial vehicles ranging from natural gas to liquified petroleum gas (LPG); natural gas can be used in a vehicle in either compressed or liquefied form. For fleets with behind the fence refueling capability, natural gas refueling stations can be set up on site to ensure that each vehicle has a dedicated fuel hose. There are two basic types of fueling equipment: fast-fill and time-fill.

Fast-fill systems combine a compressor and a high-pressure storage system. The storage system, called a cascade, fills the vehicle's fuel tank in about the same time it takes to fuel a diesel vehicle. Compressed natural gas can’t spill during refueling and drivers never go home smelling of diesel.

Time-fill systems don’t have a storage system and typically compress the gas directly into the vehicle storage cylinders to refuel vehicles while they’re parked overnight. With time-fill systems, drivers pull into their designated space at the end of their shift, connect a fuel hose to their vehicle’s natural gas cylinder and go home. Drivers don’t need to wait for their turn at the diesel pump and don’t need to wait again until their tank is full. This saves them time and saves their company money.

Natural gas exhaust systems are cheaper and easier to maintain than diesel aftertreatment systems

There are no complicated exhaust gas aftertreatment systems on natural gas vehicles. Modern diesel trucks require a set of sensors, filters and converters to scrub pollutants such as nitrogen oxides and soot from their exhaust. Some converters consume diesel exhaust fluid, or DEF, a water-based reagent whose handling can be challenging in cold weather. Natural gas burns much cleaner than diesel, so few or none of these systems are required on a natural gas vehicle. All of the exhaust is run through a simple three-way catalyst, resulting in near zero NOx levels (0.02 g/bhp-hr NOx).

It is important to closely follow recommended maintenance intervals with natural gas engines, but with proper maintenance, it’s not uncommon for natural gas trucks to reach a million miles. And mechanics often find that maintaining a natural gas engine can be a more pleasant experience because of how clean they are.

Natural gas promotes cost savings

Besides enjoying savings in terms of lower maintenance costs and reduced maintenance downtime, fleet managers can also save big on fuel costs. In the United States, the retail price of compressed natural gas has been consistently lower than the price of diesel since the start of the shale gas boom in the early 2000s. It is also decoupled from the price of oil, and therefore has been quite stable. As a result, natural gas fleet operators don’t experience wild swings in fuel prices that other fleets must deal with whenever oil prices rise and the cost of diesel jumps. This comes in addition to all the other benefits natural gas engines offer for transportation applications.

Natural gas cuts greenhouse gas emissions

Natural gas has many sustainability benefits, including 13% – 17% lower well-to-wheel greenhouse gas (GHG) emissions and 27% lower CO2 emissions than petroleum when using virgin natural gas. The benefits really shine when using renewable natural gas (RNG) made with biogas.

RNG can help fleets reach sub-zero GHG emission levels because producing RNG captures biogas like methane that would have otherwise been emitted into the atmosphere through natural decomposition. This biogas comes from the fermentation of organic waste such as animal manure in industrial digesters. Switching to renewable natural gas can be an effective way for these businesses to reach any greenhouse gas reduction objectives they may have. Many transportation businesses operating in agricultural areas have found ways to create win-win partnerships with local farmers willing to invest in a renewable gas production setup. Municipalities and refuse companies that own landfills are able to capture methane generated through waste decomposition and sell that to the RNG fuel producers, essentially offsetting their fuel costs.

If natural gas engines are relevant to your needs, don’t forget to also check our answers to frequently asked questions about natural gas engines. These answers cover topics such as cost, practicality, and feasibility of integrating natural gas into commercial fleets.

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Puneet Singh Jhawar

Puneet Singh Jhawar

Puneet Singh Jhawar is the General Manager of the global natural gas business for Cummins Inc. In this role, he is responsible for the product vision, financial management and overall performance of the natural gas business. Over his 14-year career at Cummins, Jhawar has cultivated successful relationships with a number of Cummins’ largest customers. Jhawar has extensive global experience, with roles based in the Middle East, India, Europe and the US.

Hurricane Sally no match for Florida couple and their home standby generator

Family with dog standing next to Cummins home standby generator

Three months. That’s how little time Macy and Sherry Summers had between the installation of their new Cummins QuietConnect™ home standby generator and its first major test: the arrival of Hurricane Sally.

The Category-2 hurricane stalled over the Pensacola, Fla. area for nearly 12 hours in September 2020, bringing 110-mph winds, torrential rain and major power outages. While many of their neighbors worried about their home flooding during the storm, the Summers were secure, knowing their Cummins generator would help pull them through.

“I was very concerned that if too much water got near the house, it could come in,” said Macy. “Without power, we couldn’t run our pumps, we couldn’t take the water away from our pool. That was the big fear for me.”

The new Cummins generator came through big time, powering their home and three sump pumps during the storm and running nearly 90 hours with one break for an oil change before power was restored.

Its performance was no surprise for Macy, a former Lockheed Martin engineer. Upon moving permanently into the home in 2019, he used his research acumen to find the best way to power their home through a storm. After 18 months, he decided on a Cummins QuietConnect Home Standby Generator because of the brand reputation, build quality and support.

“The brand was really important to us. We wanted to have a good support system from a large company we knew would be there if we needed it. It turns out that Cummins was the right one for us,” said Macy.

“I would certainly recommend Cummins over the brands that most people have heard of. Cummins is a stronger solution for somebody who wants that reliability.”

For the installation, the Summers contracted with Emergency Standby Power, their local Cummins dealer in nearby Fort Walton Beach, which also services and maintains the generator for them.

Said Raul Perez who oversees generator installations for Emergency Standby Power, “We try to partner with a product we know is going to be reliable that we’re comfortable servicing, that we’re comfortable installing and that we’re comfortable standing behind. That means a lot. We do like working with Cummins, because when we call and we need support, they’re always there.”

According to Sherry, the QuietConnect generator lives up to its name. “It’s amazing that when we hear it come on, we’ll always say, ‘Oh, there’s the generator. The power must be off.’ We just keep going about whatever we’re doing,” she said. 

After the hurricane, the Summers have complete confidence in their Cummins generator. Sherry says she no longer worries about food spoiling, keeping the house cool and keeping the pool pumps running. 

Macy adds, “If a hurricane comes, my peace of mind really is around these systems we’ve put in to protect our home. They’ll now have constant power, enabled by the generator.”

Find the perfect generator for your home by visiting Cummins generator size calculator.

To hear the Summers tell their own story, watch the video of them below.

Cummins Office Building

Cummins Inc.

Cummins, a global power technology leader, is a corporation of complementary business segments that design, manufacture, distribute and service a broad portfolio of power solutions. The company’s products range from internal combustion, electric and hybrid integrated power solutions and components including filtration, aftertreatment, turbochargers, fuel systems, controls systems, air handling systems, automated transmissions, electric power generation systems, microgrid controls, batteries, electrolyzers and fuel cell products.

Cummins launches new twinpack rental power diesel generator

Cummins logo at the entrance of Fridley plant

Cummins Inc. (NYSE: CMI) has launched a new 1MW twinpack rental generator, the C1000D6RE, which offers a competitive rental power solution for a diverse range of applications throughout North America. Manufactured by Cummins, a company that has been synonymous with technology, reliability and service since 1919, the new C1000D6RE model will be built in Fridley, Minnesota.

As a twinpack, the C1000D6RE combines two Cummins 15L, 500kW generators into a single, 40ft power unit, complete with aftertreatment. This enables the C1000D6RE to meet Tier 4 final emissions regulation while delivering reliable, high output performance. The generator can be used in parallel with other rental power solutions and is capable of masterless load demand.

The C1000D6RE offers a 1000kW power rating as per ISO 8528 and is powered by 2 x U.S Tier 4 Final certified QSX15 Cummins engines. The QSX15 engine meets the stringent EPA standards without the need of a Diesel Particulate Filter (DPF) which offers ease of serviceability, lower emissions and greater performance.

A new heavy-duty trailer and hitch design ensures even greater reliability for rugged mobile power applications. The generator’s container is capable of withstanding extreme weather conditions, while a full sound attenuation package minimizes the generator’s noise levels. For faster and cleaner oil changes, a ‘Quick Fit’ oil evacuation system option is also provided.

Weighing in at 69,000lbs with fuel, the C1000D6RE comes equipped with a front-end stabilizer and mobile air-ride to reduce the impacts of travel, minimizing potential down time.

The C1000D6RE is suitable for use across a wide range of large-scale industries requiring rental power, including: construction sites, emergency power, large scale events, industrial buildings and utilities located in remote locations or urban areas.

John Gibbons, Rental Power Markets Director at Cummins, said: “We’ve listened to our customers and developed the C1000DR6RE specifically to meet their demands. We also wanted to prioritize the production of a generator that continues to provide reliable power solutions, regardless of climate, location or industry. We believe this product will provide markets with greater reliability, improved performance and increased flexibility.” 

The 1MW twinpack model can be used for a diverse range of industries requiring mobile power; ranging from construction sites, industrial buildings and utilities located in remote locations or urban areas. The remote start and stop contact functionality allows the generator set to be switched on and off upon demand without the need of local maintenance support. As a result, customers can expect more stability, greater uptime and lower labor costs leading to lower total cost of ownership.

To ensure continued performance, Cummins offers customers servicing and maintenance of its mobile power generator range. Cummins aftermarket capabilities are provided through a network of over 200 local sales and service locations across North America; supported by a global system of service technicians, engineers and part distribution centers, experienced in offering mobile power solutions to fit any power requirement.

Cummins Office Building

Cummins Inc.

Cummins, a global power technology leader, is a corporation of complementary business segments that design, manufacture, distribute and service a broad portfolio of power solutions. The company’s products range from internal combustion, electric and hybrid integrated power solutions and components including filtration, aftertreatment, turbochargers, fuel systems, controls systems, air handling systems, automated transmissions, electric power generation systems, microgrid controls, batteries, electrolyzers and fuel cell products.

Euro 7/VII - the missing puzzle piece for improving air quality in Europe

Euro 7/VII - the missing puzzle piece for improving air quality in Europe

The environment is facing an existential crisis and we need to act now by cutting emissions to address poor air quality and stop climate change. Policy makers, industry, academia, and thought leaders must work together to neutralise those threats. The upcoming Euro 7/VII regulation proposal, if ambitious, has the potential to make a significant difference. 

Melina Kennedy, Vice President – Product Compliance and Regulatory Affairs at Cummins Inc.
Melina Kennedy, Vice President – Product Compliance and Regulatory Affairs at Cummins Inc.

The EU is a trail blazer in climate policy and has set clear ambitions to be climate neutral by 2050, through the ambitious European Green Deal. The Fit for 55 Package has been an excellent set of measures to spur the transition, and the RepowerEU plan will now hopefully function as the catalyst needed to create change even quicker. The piece of the puzzle still missing to speed up the transition is the proposed regulations for Euro 7/VII for cars, vans, and heavy-duty vehicles.

At Cummins, we are committed to reaching zero emissions through our Destination ZeroTM strategy. We fully support a tough, clear, enforceable Euro VII regulation that allows us to compete on a level playing field and provides real benefits to the environment. Our technical experts are confident we can meet ambitious targets, and we hope the regulation proposal reflects those ambitions when published.

The European Green Deal strategy mirrors our own Planet 2050 plan at Cummins, where we hold ambitions for all our facilities, operations and products to become climate neutral by 2050. Cummins is a global technology leader committed to meeting the world’s sustainability challenges. We have been innovating for well over 100 years and have a strong footprint in Europe where we design, manufacture, sell and service a broad portfolio of power solutions for transport and energy applications.

On this path to a zero-emission future, adopting cleaner technologies today, like near-zero natural gas products and nearer-to-zero diesel, prior to widespread commercialization of zero-emission technologies for all markets, can make an immediate, positive impact. The Euro VII regulation and its interaction with the heavy-duty vehicle CO2 regulation, therefore, is critical for cutting emissions and improving air quality at the beginning of this journey to a zero-emission future. That near-term step is critical for the heavy-duty sector which, from an air quality and emissions perspective, is much harder to abate than other sectors due to their typical usage demands and weight.

For industry to innovate, we need a clear roadmap and timetable from policy makers on what regulations are approaching in coming years. As the world’s largest independent engine manufacturer in the heavy-duty space, knowing and understanding the Euro VII regulation in full detail is critical to our business and that of our customers.

The regulation timing determines our product planning, technology development, investment decisions and our path to zero-emissions. Any further delay to the proposed July publication of the Euro VII regulation proposal is very difficult for those in the industry who require time to innovate, develop and launch product. We hope the Euro VII regulation will remain on its latest updated schedule, as there is a high level of complexity and corresponding time needed to deliver a new engine technology platform. Cummins is ready to meet the demands of a stringent regulation, but it would require new base engine hardware, new software, new aftertreatment architectures and components, to name just a few. And we want to be sure the lead time is adequate so that the necessary innovation can take place to benefit the environment, our customers and end users with new and reliable technologies.

There is no silver bullet for the heavy-duty sector on the path to zero-emissions. A suite of different power solutions will be needed to meet Euro VII requirements and reach destination zero goals set out in the European Green Deal. Policy proposals taking a technology neutral approach are critical for innovation and will ensure that the Euro VII proposal will be successful. On our innovation journey for the heavy-duty sector, Cummins has unveiled the industry’s first fuel-agnostic internal combustion engine platform, which can be specified to run optimally on different fuels, including diesel, renewable natural gas, or hydrogen. These technologies can enable our customers and end users to step away from fossil fuels and affordably meet the Euro VII requirements.

Cummins has been investing heavily in zero-emission technologies, spending over $1.07 billion (€1 billion) in research and technology each year. Cummins is now a world leader in battery and hydrogen technology, with much of this work taking place in Europe. Cummins has a fuel cell manufacturing plant in Herten, Germany, providing power solutions for trains and trucks. Cummins is one of the world’s largest manufacturers of electrolyzers for green hydrogen production, with facilities in Belgium and a future plant in Spain. And we have a joint venture with NPROXX for manufacturing critical hydrogen tanks for storage and transport in Germany. These are all technologies essential to the creation of a hydrogen economy here in Europe, and to the success of the European Green Deal.

The heavy-duty engine and vehicle industry in Europe has faced more significant challenges over the past three years than in living memory. Brexit, Covid, significant supply chain shortages, and now the crisis in Ukraine. Having a period of regulatory certainty with clear deliverables, whilst meeting the challenge set out in the European Green Deal, will be key to the sector’s success. We ask that the impending Euro VII regulation proposal is timely, clear, ambitious, and technologically neutral in its approach. If so, it would address a missing puzzle piece in turning the corner for the sector, for a more sustainable and prosperous future in Europe.

Melina Kennedy

Melina Kennedy is the Vice President – Product Compliance and Regulatory Affairs for Cummins Inc. Prior to that she served as the Director of Executive Communications at Cummins Inc. where she developed and implemented high level strategies to meet the key communication needs of our senior leaders. Melina is a former candidate for Mayor of Indianapolis and Counsel at Baker and Daniels. She previously served as Director of Economic Development under former Mayor of Indianapolis Bart Peterson where she harnessed her talent as a leader and communicator.

Onan SD20 Generator powers mobile business in Richmond, Va.

Multicolored mobile business powered by SD20 Generator

Located in Virginia, The Sweet Xscape, formally known as Envy’s Whadder Ice, started in 2020 when the pandemic began. Owner and sole proprietor Tierra Mclaurin shared: “I’ve always wanted to get into the Italian Ice business, and this was the perfect time to start since we were on lockdown.”  

McLaurin started small with selling Whadder Ice out of her car with coolers. Once the city started to open up, she wanted to legitimize her business and purchase a truck. Now, McLaurin sells an entire line up of treats including her original Whadder Ice. 

“It’s not only about the quality of the product but it’s the unforgettable experience,” States Mclaurin. Sweet Xscape specializes in blending cereal-infused milkshakes, sundaes, Whadder ice, vegan treats and more.

Sweet Xscape’s premier item, “The Main Event”, is the reason Mclaurin purchased the Onan SD20 generator from Cummins. "We needed a generator with power, and big enough to operate our machine that runs at 16,000kw.  Cummins supplied exactly what we needed."

When Mclaurin began to ask around about generators, her ice cream vendor recommended the Onan SD20, sharing that she would need 16,000 watts in order to power her business. After having the opportunity to see the generator in action in a demo truck, she was sold and excited at the opportunity to realize her dream and bring a unique business to her city.

After thinking she would have to pull a string to crank the generator, Mclaurin was surprised about how easy the Onan SD20 was to operate. “The SD20 is very simple to operate. All you have to do is flip the switches on. After that, it prompts you on which buttons to push to get it running,” she explains. “Once connected to the system you no longer have to go outside the vehicle to get it started. It’s just the flip of a switch and the generator is up and running.”

Mclaurin sitting next to Onan SD20 generator placed inside the mobile business

Having the Onan SD20 allows Mclaurin to provide the ultimate soft serve ice cream experience. “The SD20 allows me to produce multiple cones which is the goal to get my customers served.”

Opening this summer, Sweet Xscapes’ season is just warming up. “Having a reliable generator, we’re not going to miss a beat. Imagine having peanut butter and jelly on an ice cream cone? Thanks to Cummins, we have it at The Sweet Xscape. This generator was well put together, easy to use, quiet and top tier.”

If you’re in need of a heavy-duty generator don’t cheat yourself, treat yourself to the Onan SD20.”

Cummins Office Building

Cummins Inc.

Cummins, a global power technology leader, is a corporation of complementary business segments that design, manufacture, distribute and service a broad portfolio of power solutions. The company’s products range from internal combustion, electric and hybrid integrated power solutions and components including filtration, aftertreatment, turbochargers, fuel systems, controls systems, air handling systems, automated transmissions, electric power generation systems, microgrid controls, batteries, electrolyzers and fuel cell products.

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