By Darren Tasker
The U.S. Environmental Protection Agency‘s latest Tier 4 final standards for diesel engines, intended to reduce NOx and particulate matter up to 99% compared to previous tiers, have left many in the industry with questions. Stationary diesel engines are used in a variety of facilities, and executives are eager to understand how newer, more environmentally friendly options will align with their evolving business and sustainability objectives.
Despite the proven results of Tier 4 Final diesel solutions—particularly from an overall cost of ownership, reliability, and emissions standpoint—misconceptions remain in the market. This article will explore some the benefits new diesels bring compared to natural gas alternatives and dispel potential confusion facility executives may have in navigating the evaluation process.
Stacked Up To Natural Gas
Deploying a diesel solution to meet Tier 4 Final emissions standards offers several practical benefits for applications from standby power to power generation, including increased efficiency, compact installation, and less complexity in both cost and reliability. Compared with a natural gas, diesel fuel is less flammable and easier to maintain. Diesel fuel can be stored on premise as opposed to needing natural gas lines, which could be disrupted and lead to shutdowns. Additionally, while natural gas engines have traditionally been quieter, new mufflers and catalyst components are available with modern Tier 4 Final diesels that significantly reduce noise levels.
To curb NOx emissions, advanced Tier 4 Final diesel solutions use a Selective Catalytic Reduction (SCR) process that injects a diesel exhaust fluid (DEF) into the exhaust. The DEF breaks down emissions into harmless nitrogen and water vapor. At the same time, these engines are designed to reduce particulate matter in the engine’s cylinder with a highly efficient combustion process.
Tier 4 Final engines have been used reliably for over a decade in Europe and America in trucks, buses, and off-highway equipment. However, facilities may need time to better understand the impact and performance of these solutions, which are relatively new in off-road industrial applications.
Myths And Realities
Much of the uncertainty surrounding Tier 4 Final diesel engines has been centered on core objectives in cost, maintenance, and reliability. Facilities may lack understanding of how environmental mitigation measures impact their efficiency and value.
Here are some common myths about Tier 4 Final diesel engines.
Myth 1: Tier 4 Final diesel engines come with a hefty price tag.
Facilities should examine the total cost of ownership (TCO) and other benefits that can be achieved when assessing their needs and possible solutions. For example, Tier 4 Final diesel gensets are often used for peak shaving, load management, and resolving capacity constraint with utilities. These features and/or other electric market benefits can offset costs and contribute significantly toward paying for the Tier 4 Final solution. In many cases, these engines are less costly in initial acquisition and TCO in comparison with a Tier 2 system with aftertreatment.
Myth 2: New diesel engines are complex and difficult to maintain.
Tier 4 Final diesels are designed to be a simple and reliable solution that can also allow for continued operations. Volvo Penta’s Tier 4 Final engine range requires the same amount of maintenance as previous iterations with only two major components: the SCR and non-cooled EGR. This streamlined framework reduces installation costs and allows for better flexibility to conduct testing and system checks that help maintain reliability. The latitude to run an emergency backup system without restrictions with a more environmentally friendly system can also help to ensure uptime in facilities like data centers.
Myth 3: Emission mitigation means a shorter lifetime.
Diesel engines have proven to operate well for significant periods of time in demanding applications, the aftertreatment systems also have been refined to provide the same reliability and operational benefits. An emissions-mitigating diesel solution that incorporates an air throttle and EGR within the system’s SCR will have a maximized lifespan. The air throttle controls the amount of air entering the engine, which in turn affects the exhaust temperature that determines how much particulate matter is burned off by SCR. The throttle closes partially during light loading to maintain the necessary engine temperature for meeting those requirements. Together, these elements provide a simple solution for Tier 4 Final while reducing wear in the engine over time and improving reliability.
Myth 4: Provider services end at installation.
Facilities should consider partnering with a provider that can make a lifecycle commitment to installation and management. Expert-level solutions providers will take a full-facility, lifecycle approach to service that takes companies through production and management of their microgrid. By combining product innovation with experienced service oversite, facilities can ensure they’re getting the best value from their solution.
Strike The Right Balance
Sustainability is a growing priority for many facilities, but emission levels aren’t the only consideration. Facility executives should weigh environmental care objectives such as fuel economy and ease of installation with differentiation like durability and reliability to ensure performance demands are met. By investing in a strategic solution, facilities can optimize operational efficiency while lowering the environmental impact and maximizing the value of their power solutions.
Tasker, vice president of industrial sales at Volvo Penta, oversees the company’s development in power generation and off-road versatile equipment segments within North and Central America and the Caribbean. He joined the company in 1996 as area account manager and internal sales engineer and has served as UK industrial sales manager, off-highway project director for Europe; and director of industrial business for the Americas.