SCR versus EGR: What's the right choice for the rail industry?

Today, there are two core technologies to reduce emissions within the rail industry: Selective Catalytic Reduction (SCR) and Exhaust Gas Recirculation (EGR). But how do you know which is the right technology for your customers?

A quick internet search for “SCR vs. EGR” will return more than two million results from various sources, but what does it all mean? For decades, people have been debating the merits of each technology, arguing over which is better. We’d argue, however, that the question you should be asking is this: Which technology is right for your customers?

In this article, we’ll provide a clear and practical explanation for SCR and EGR technology in the rail industry.

First, a little background on the SCR vs. EGR technology debate.

EGR or SCR for the rail industry
A mix of technologies - from electronics and controls to aftertreatment sytems - are used in the race towards near-zero NOx engine emissions. 

Emission regulations for engines used in heavy-duty applications - from on-road vehicles to locomotives - started in the 1990s and became more stringent in the 2000s. Locomotive manufacturers were able to meet these emission regulations without the use of exhaust gas aftertreatment technologies in most applications. On the other hand, heavy-duty on-road engine manufacturers had to meet more stringent regulations compared to railway locomotives. 

In the 2010s, as emission regulations got more stringent, several heavy-duty on-road engine manufacturers needed to use a combination of SCR and EGR technologies to achieve the required emission levels. For the rail industry, where most applications require the use of larger engines, several engine manufacturers had to choose between SCR or EGR to meet the new emission regulations. This was the beginning of the debate between SCR and EGR technologies. 

A Better Question: What is the right emission reduction technology for your customers? 

From rail operators to locomotive manufacturers, rail industry players have needs unique to their business models and markets served. Instead of making the technology choice the starting point, we have outlined three use cases and the right aftertreatment technology.   

When running hours and fuel consumption makes the engine efficiency an important parameter

Challenge: As regulations require pollutant emissions deceased, engine manufacturers could adjust engine parameters to partially lower the emission of pollutants.

Combustion temperature is one of these parameters, however, a lower combustion temperature reduces NOx emission yet increases fuel consumption. For rail operators focusing on improving fleet utilization, increased fuel consumption could negatively impact their financials and worsen their environmental impact. 

Opportunity: Rail operators can optimize engine combustion for higher fuel efficiency and choose to reduce NOx separately through SCR, since SCR is a solution external to the engine. Given the high proportion of fuel costs in rail operators’ overall running costs, rail operators would likely offset the additional cost of diesel exhaust fluid (DEF) over time through the fuel consumption savings.

When reliability matters, and you want to build upon an already reliable engine

Challenge: Engine manufacturers have the option to introduce varying levels of engine design changes to meet the more stringent emission regulations. For locomotive manufacturers, any extensive change in engine design raises the question of engine reliability. This concern is further amplified for engines, such as the Cummins QSK50 and QSK60, which have proven their reliability over many applications and millions of hours of usage.

Opportunity: Locomotive manufacturers could lower the risk of adversely impacting engine reliability by choosing engines that didn’t go through significant architectural design changes and new part introductions from an engineering perspective. SCR technology helps the engine meet emission regulations with limited architectural design changes in an engine’s combustion chamber.   

When a high degree of commonality helps you create a financial edge through operational savings

Challenge: As emission regulations vary across regions, locomotive manufacturers and rail operators face a dual challenge: offering products that are fit for local needs, while increasing their financial performance. 

Opportunity: Use of SCR technology would likely allow locomotive manufacturers to have higher commonality across variations within a given engine platform. This offers financial and operational benefits. For instance, rail operators managing a fleet with higher engine commonality will benefit from common service methodologies while managing fewer parts. 

“We expect the locomotive manufacturers and rail operators using engines with SCR technology today to be better positioned in the near future when the emission regulations get more stringent. Today’s SCR technology is well suited to meet future emission regulations with less interventions, positioning users of SCR technology a step ahead of users with other emissions technologies,” says Miranda Cross, Global Rail Account Manager of Cummins Power Systems.

Bottom line, it is important to evaluate your customers’ key needs and use cases before making the technology decisions. For customers with the above three use cases, SCR offers a combination of financial and environmental benefits, including greenhouse gas reduction, while also helping locomotive manufacturers and rail operators meet unique local needs.   

To learn more about trends and technologies in rail industry follow Cummins  on Facebook and LinkedIn. To learn more about rail power solutions Cummins offers, visit our webpage. 

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Aytek Yuksel - Cummins Inc

Aytek Yuksel

Aytek Yuksel is the Content Marketing Leader for Cummins Inc., with a focus on Power Systems markets. Aytek joined the Company in 2008. Since then, he has worked in several marketing roles and now brings you the learnings from our key markets ranging from industrial to residential markets. Aytek lives in Minneapolis, Minnesota with his wife and two kids.

The F/V Sea Hound: Bringing work hard, play hard to life

FV Sea Hound

A commercial fishing boat brings prosperity and comradery to the New England fishing community. 

On the weekends, Chris Devine trades in his pharmacist lab coat for his foul weather fishing gear to spend time on the F/V Sea Hound – his beloved 37-foot lobster boat. According to Chris and his partner, Troy Collins, every waking moment spent off the New England coast is time well spent. The pair carry over 800 traps to sea each weekend with intentions to only return once their boat is overflowing with the day’s catch. 

As soon as they were old enough, childhood friends Chris and Troy began working on charter fishing boats along the New Hampshire (USA) coast. Once in college, Chris also started lobstering over the summers to pay for his education. Little did he know that his side gig would cultivate a new passion and become a life-long hobby. 

Chris bought his first boat at the age of 18 and has had two others since then. He started with only 100 traps on his 27-foot skip boat and has now worked his way up to his current vessel, the F/V Sea Hound.

F/V Sea hound

Purchased in northern Maine, only minutes from the Canadian border, the F/V Sea Hound required some major work before it could hit the water. Chris and Troy trucked the boat down to their hometown of Hampton, New Hampshire (USA) where it lived in the shipyard for eight months. 

The duo had the original Cummins B-series engine rebuilt, then two years ago upgraded to a remanufactured Cummins C-Series 8.3L engine. Reflecting on his experience with Casco Bay Diesel, a Cummins dealer, Chris says, “Honestly, the reliability of the product and the ease of work and connection is amazing. Everyone is a phone call away and so willing to help.”

While they love their weekends lobster fishing, the F/V Sea Hound gets plenty of use for other fun excursions. Devine and his wife Haley will use the boat for offshore fishing tournaments, date nights on the coast, snorkeling, sunset cruises and so much more. 

Haley mentions the comradery that the vessel brings for their friendships and fishing community. “The boat has brought a lot of our friends closer together, they enjoy helping out, fixing things and building things. It has truly created a family, and everybody loves it.”

She says, “The lobster community can be so cut throat, but at the same time these guys have such a bond. They will give you anything and everything they can to ensure your boat is up and running. Everyone will be there to help.”

F/V Sea HoundJoking about all the love for the F/V Sea Hound, Haley says, “I like to refer to the boat as the dirty mistress. But as much as I make fun of it, it has been an awesome experience and we are truly lucky to own a boat and be a part of the fishing community.”

The F/V Sea Hound is absolutely adored by her owners, deckhands, family and community. It brings so much joy, not only in the form of weekends lobster fishing but also with leisurely activities on the water and the wholesome environment it provides.

For mariner families like Chris, Haley and Troy, there really is no better place to be than the open water.

Want to see and learn more about the F/V Sea Hound? Check out their Instagram page

Looking for information about Cummins Marine? Visit cummins.com/marine

Cummins Office Building

Cummins Inc.

Cummins is a global power leader that designs, manufactures, sells and services diesel and alternative fuel engines from 2.8 to 95 liters, diesel and alternative-fueled electrical generator sets from 2.5 to 3,500 kW, as well as related components and technology. Cummins serves its customers through its network of 600 company-owned and independent distributor facilities and more than 7,200 dealer locations in over 190 countries and territories.

How will the future worksite reduce its environmental impact?

Cummins Worksite of the Future -

This article is part of our 'Worksite of the Future' series of articles, where we look at the trends that will shape the future of the construction industry. 

Today’s cities are rapidly changing as they race to decarbonize. So, how does this impact the construction industry? According to the World Green Building Council (WorldGBC), 11% of the world’s carbon emissions come from the construction industry; producing the materials and constructing the buildings. The WorldGBC issued a vision in September 2019, outlining how these carbon emissions could be reduced 40% by 2030 through many collaborative actions, including ambitious public procurement policies and clean and lean construction processes. 

Cummins Inc. is supporting this initiative through powering construction equipment on site. Our business strategy and product portfolio are evolving to meet the needs of our customers and the environment, holistically, with current and new technologies. But, how does this relate to the construction site of the future? 

Innovation: Powering the Worksite of the Future

For over 100 years Cummins has been a leader in advancing diesel technology. Efficient combustion strategies coupled with sophisticated air-handling and aftertreatment technologies have enabled Cummins engines to reach near zero emissions levels, exceeding many of the current regulations around the globe. The same technology advancements that contributed to reduced emissions have also produced higher power density, more torque and quieter operation than earlier engine versions. The latest Performance Series product line-up, ranging from 3.8L to 15L (75-503 kW), produces on average, 10% more power output and 20% more torque than their predecessors. Higher power density and more torque from these engines contributes to more productive machines, and in some cases reduces the size of the engine needed for the machine.  

Cummins will continue to innovate diesel engine technology, as we believe it will be an integral part of many industries for years to come. The higher horsepower from a smaller, lighter package seen in our Performance Series engines is a pointer to where we expect the development of advanced diesel to continue in the future.

Simultaneously, new technologies are emerging including electrified systems and hydrogen fuel cell. Solutions such as these will be needed as the construction community seeks to reach sustainability plans introduced by WorldGBC, local municipalities and other organizations. To demonstrate capabilities Cummins has worked with two well-known OEM partners, Hyundai and XCMG, to produce the world’s first Cummins powered electric mini excavators featuring Cummins BM4.4E battery modules. Both machines eliminate gaseous tailpipe emissions and nearly eliminate operational noise. 

Mini excavators and other compact construction equipment are prime candidates for early adoption of these electric systems because of how and where they are typically used. These machines are designed for small and mid-sized projects requiring a lighter duty cycle than their larger cousins. Their compact size makes them a great fit for smaller crowded sites often found in densely populated urban areas. Coincidentally, urban areas are increasingly seeking noise and emissions reductions to comply with city ordinances and air quality targets. Other light and medium duty cycle applications such as wheeled loaders and telehandlers will also be good candidates for electric drive systems. 

Heavy-duty cycle applications such as full-sized excavators, graders and mobile cranes will continue to rely on advanced diesel such as the new performance series product line, or hybrid systems to get the job done for years to come. In a hybrid application, the drivetrain combines diesel and electric power for more efficient operation. This could be in a mild, parallel or series configuration depending on the type of machinery and its duty cycle. Whichever system is used, fuel consumption and emissions are reduced. From a business perspective, the savings needs to be enough to pay for the additional cost of the hybrid technology which is not always the case.

Similarly, fuel cells could be applied in much the same way a diesel engine is used in the hybrid system. The fuel cell delivers a steady electrical feed to the battery or batteries, eliminating the need for a recharge period. Fuel cell systems will allow heavy duty machines to act much like their diesel counterparts without impacting their performance or downtime, while being completely emissions free, aside from harmless water vapor. While theoretically this seems like a great option the business case just does add up yet. Sustainable production of hydrogen is also a challenge that needs addressing before hydrogen becomes a main stream fuel source for the construction industry.   

Ensuring Environmental Sustainability

Preserving the environment is an important initiative, and Cummins’ dedication to affect change goes beyond the products. Our recently released PLANET 2050 strategy outlines how we will do our part to address climate change and other global environmental challenges. Future construction sites will adapt by improving the efficiency of diesel-powered machines and begin using machines with alternative fuels and other technologies to reduce their carbon footprint. Cummins will partner with our customers to deliver the right technology for the application at the right time.

Learn More and Join the Conversation

Join the conversation with #Cummins on your social platforms or visit https://www.cummins.com/engines/construction to learn more about our current and future product solutions. We also have Cummins experts around the world happy to answer your questions. Find your nearest Cummins professional by visiting care.cummins.com or calling 1-800-Cummins. 

Cummins Office Building

Cummins Inc.

Cummins is a global power leader that designs, manufactures, sells and services diesel and alternative fuel engines from 2.8 to 95 liters, diesel and alternative-fueled electrical generator sets from 2.5 to 3,500 kW, as well as related components and technology. Cummins serves its customers through its network of 600 company-owned and independent distributor facilities and more than 7,200 dealer locations in over 190 countries and territories.

Dropping the sails and powering up with Cummins

MV Brigadoon

Cummins engine receives a major overhaul after boat owner commits to a power vessel after years spent sailing the Pacific Northwest.

A couple from Seattle, Washington (USA) spent the first half of 2020 refitting their new Hampton 490 Pilothouse power boat. Chris Jones grew up around marinas and has owned a variety of boats throughout his life. Most recently, he and his wife have been cruising around the Puget Sound in their Hunter 46 sailboat. But with the turn of the new year, they decided to trade in the slow and steady lifestyle of sailing for a new power boat – the M/V Brigadoon.

After identifying they were ready to make the switch back to faster speeds, Chris and his wife began narrowing down what kind of vessel they were looking for. After weeks of extensive research, they found two Hampton boats available that met their requirements for quality, systems and seaworthiness.

Jones ventured down to California to look at one of the options, and at first glance thought the vessel had too much work to be done. But as the couple explored other boats, even comparing her to the alternative Hampton in the area, they found the M/V Brigadoon had the most potential.

But it would not be without major rework. The vessel needed a massive overhaul for the engine, control systems, and cosmetics. The 20-year-old boat only had 800 hours on it, which is quite low for an engine of that age. After years of sitting idle, it needed some tender love and care.

MV Brigadoon - Cummins

With an eye for improvement, Jones left his new acquisition in the hands of Marine Diesel Services in Newport Beach, California. The significant overhaul of his Cummins 6CTA 8.3 series engine included replacing aftercoolers, turbo chargers, hose clamps, seals, etc. Chris said, “They really did fantastic work on the boat. I have a lot of confidence in the power plant and that it has been adequately serviced.”

Once the mechanical work was complete, the M/V Brigadoon was ready to be delivered to the Pacific Northwest. At Emerald Harbor Marine, she received electrical work and new alternators, wiring, and navigation system. Finishing touches included more minor maintenance and a fresh paint job.

MV Brigadoon - Cummins

Six months have passed since the Jones’ heralded the M/V Brigadoon as their own. In mid-July, they put their new baby into the water for their first cruise since stepping off their sailboat last year. Looking forward to the speed and freedom of a power boat once again, they intend to vacation in the San Juan islands during their shakedown cruise and find new ports to explore.

For more photos and information about the M/V Brigadoon refit or to follow her journey, check out Chris Jones’ Instagram.

Katie Yoder - Cummins Inc.

Katie Yoder

Katie Yoder is a Marketing Communications Specialist. New to Cummins in 2018, Katie joined the marketing operations team where she supports trade show initiatives in North America. As a University of Wisconsin alumna, Katie enjoys watching Badger sports in her free time.

How technology can help customers save over $30 million in fuel and avoid enough pollutants to fill a 15-mile long train

Think of a train loaded with 40 foot containers as long as the distance between your home and work (about 15 miles). This is what it would take to load all the pollutants avoided, thanks to the state-of-the-art technology used in Cummins Tier 4 high horsepower engines.

Cummins Tier 4 high horsepower engines have recently exceeded 10 million operating hours. These engines feature state-of-the-art technology significantly reducing the emission of environmentally harmful pollutants such as particulate matter (PM) and oxides of nitrogen (NOx). You can see these engines featuring the latest emissions technology in operation in many applications ranging from railroad locomotives and marine vessels, to mining and oil and gas equipment.  

Let’s cover two reasons why Cummins’ Tier 4 technology is increasingly popular across many industries.

Reduced fuel usage means over $30 million of financial gains for customers and over 300,000 barrels of fuel savings for our planet

Owners of Cummins Tier 4 high horsepower engines are enjoying lower operating costs, since the fuel efficiency of these engines improved by up to 5% over Tier 2 engines, depending on the equipment duty cycle.

With 10 million running hours so far, we estimate our customers using Cummins Tier 4 high horsepower engines have experienced over $30M  of financial gains in the form of reduced fuel costs. This also translates into over 300,000 barrels of fuel savings for our planet.

Reduced environmental footprint is equal to removing the pollutants produced by over a half million cars

The technology Cummins uses in its Tier 4 engines significantly reduces PM and NOx emissions compared to earlier Tier 2 applications. PM contains microscopic solids or liquid droplets that are harmful to human health. A Tier 4 high horsepower engine with Cummins technology reduces PM emissions by 80% over a Tier 2 counterpart. NOx is most commonly known as the cause of smog, the brown sky often seen in large cities, and it also causes acid rains. A Cummins Tier 4 high horsepower engine emits 45% less NOx than a Tier 2 counterpart. 

Tier 4 technology delivers significant reductions in emission of harmful pollutants
Tier 4 technology delivers significant reductions in emission of harmful pollutants

These reductions in the environmental footprint add up quickly; 10 million operating hours across these Cummins engines translates into over 50,000 tons of PM and NOx avoided. Just the reduction in NOx emission is equivalent to taking more than 600,000 cars out of traffic for a year.

“Our mission at Cummins is to make people’s lives better by powering a more prosperous world, and this comes in many forms. In this case, our technology is helping our customers reduce their environmental footprint and decrease their operational costs while they enjoy excellent productivity,” said Gary Johansen, Executive Director of Power Systems Engineering at Cummins Inc.

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Aytek Yuksel - Cummins Inc

Aytek Yuksel

Aytek Yuksel is the Content Marketing Leader for Cummins Inc., with a focus on Power Systems markets. Aytek joined the Company in 2008. Since then, he has worked in several marketing roles and now brings you the learnings from our key markets ranging from industrial to residential markets. Aytek lives in Minneapolis, Minnesota with his wife and two kids.

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