The off-highway equipment industry is facing the challenges that go along with integrating new ultra-clean emissions machines through the Tier 4 Final regulations that extend through 2014. This clear path to reduce emissions with Tier 4 Interim regulations starting in 2011 required companies to look outside engine technologies such as high-pressure fuel systems, engine timing, combustion, turbocharging, and electronics to aftertreatment innovations.
These innovations not only help to meet the latest regulations but can also lead to more fuel-efficient products that produce less CO2 in the future. Looking beyond Tier 4 Final regulations, one can assume technologies such as onboard diagnostics, telematics, various hybrid systems, or waste-heat-recovery methods will become more common in our industry as we look toward the future of efficient diesel power.
In 2008, Cummins announced that our EPA Tier 4 Interim engines for 2011 would have an improved fuel efficiency of up to 5% and improved response while maintaining Tier 3 levels of durability. After announcing this technology, many of our OEM customers worked with prototype products ahead of 2011.
Partnering with our customers' engineering staffs, we worked with the OEMs on efficient ways to not only integrate the systems but also improve efficiencies in cooling systems, hydraulics, and other equipment systems to further reduce fuel consumption. This work not only validated our fuel economy improvements but several customers saw Tier 4 Interim fuel economy improvements as high as 10% compared to Tier 3.
Cummins designed Tier 4 Interim products with Tier 4 Final in mind. Our engineering staff worked hard to ensure that our Tier 4 Final system also included a fuel economy advantage of up to 3%, easily offsetting the additional cost of diesel exhaust fluid. OEMs that have planned ahead only need to incorporate a selective catalytic reduction system downstream of the exhaust. This system, while new to Cummins off-highway customers, is not new for Cummins as we have hundreds of thousands of these systems in our on-highway applications. Leveraging this experience, we’ve also added technology to make this a next-generation system designed for off-highway applications.
Beyond the industry’s focus in complying with upcoming Tier 4 legislation, we have an obligation to our customers—and more broadly, the general population—to manufacture products that produce fewer emissions and provide higher fuel efficiency. These fuel efficiency gains translate into lower operating costs for our customers as well as a reduction in the amount of CO2 in the atmosphere. While the EPA has not made any official regulations after Tier 4 Final, it is expected that future regulations beyond Tier 4 Final will be similar to the CO2 regulations that are coming for the on-highway market.
While these CO2 standards are currently not regulated, global climate change efforts and sustainability pressure are likely on the horizon, and our new Tier 4 products will help reduce CO2 emissions with improved fuel economy. For example, an average hard-working Tier 4 Final industrial machine with this lower fuel consumption will easily have a reduction of 8 ton (7.3 t) of CO2 greenhouse gas emissions every year compared to Tier 3.
In early 2010, Cummins received approximately $54 million in funding from the Department of Energy for projects aimed at increasing fuel efficiency in heavy- and light-duty vehicles. The research from this funding can later be transferred for future off-highway applications if applicable.
These efforts to reduce fuel consumption from today’s machines could also include future diesel technologies such as diesel-hybrid machines, diesel-electric drives, or hydraulic hybrids. While these technologies are more common in on-highway markets compared to off-highway, they do offer real possibilities for the industry that will complement the introduction of Tier 4 ultra-clean equipment. Cummins is also the leading manufacturer of diesel engines for on-highway hybrid applications and has leveraged this experience for several off-highway hybrid installations. By choosing the right alternative energy for the right application, these technologies can achieve significantly reduced emissions and fuel consumption.
For industrial applications that do not have stop-and-go conditions or operate a large amount of hydraulics, technologies such as waste-heat recovery might be more beneficial. Waste-heat recovery, like a hybrid system, tries to re-use as much wasted energy as possible. Waste-heat-recovery systems are possible solutions for both on-highway line-haul applications and applications such as tractors and haul trucks.
Regardless of the technologies that are implemented in the future to reduce our emissions and increase fuel economy, these technologies must also keep the customer in mind. Technologies that are not fully tested, improperly implemented, poorly interfaced with operator controls, or that oppose customer demands will simply not be accepted in the market. Voice-of-customer input is even more critical as we look toward education, training, and operating and installing the future technologies for the off-highway industry.
Jeff Weikert, Vice President–Cummins MidRange Engineering, wrote this article for SAE Off-Highway Engineering.