48V Electrical Systems: A Key to Meeting Evolving Industry Demands

Manufacturers are exploring innovative solutions to enhance performance while optimizing fuel consumption. Moving to a 48V architecture offers multiple benefits in this quest.

June 1, 2025

The commercial vehicle industry is at a turning point, facing increasing pressure to improve efficiency, reduce emissions, and meet changing global standards. As vehicle electrification advances and power demands rise, manufacturers are exploring innovative solutions to enhance performance while optimizing fuel consumption. One promising technology trend leading this transition is the adoption of 48V electrical systems. These systems, which represent a significant upgrade from traditional 12V and 24V architectures, offer multiple benefits, including enhanced vehicle efficiency, improved power management, and greater adaptability to emerging industry requirements.

Meeting Changing Industry Standards

As the commercial vehicle sector evolves, so do the standards and expectations surrounding vehicle efficiency and emissions reduction. New benchmarks are continually introduced to encourage manufacturers to adopt cleaner and more efficient technologies. To stay ahead, vehicle makers must integrate advanced solutions that not only improve performance but also align with the broader shift toward electrification.

One of the most significant challenges commercial vehicle manufacturers face is balancing these new requirements with the increasing power needs of modern trucks and buses. From advanced driver assistance systems (ADAS) to electrified HVAC systems and emissions control technologies, vehicles now demand more electrical power than ever before. Traditional 12V and 24V systems struggle to meet these growing demands efficiently, making 48V architectures an ideal solution.

Increased Power and Efficiency

The Eaton aftertreatment e-heater controller is an air-cooled, power-electronic converter designed to regulate 48V to a catalyst heater element for commercial vehicle emission control applications. The controller can control a total of 200 amps of load current to a resistive heating element. (Image: Eaton)

Modern commercial vehicles require extensive electrical power to operate critical systems, from air conditioning compressors to cooling fans and power steering pumps. In conventional designs, these components are often mechanically driven by the engine, creating parasitic losses that reduce fuel efficiency. By shifting these functions to a 48V electrical system, manufacturers can significantly cut energy losses, improving fuel economy by up to 2 percent.

Beyond direct fuel savings, this transition also enhances vehicle design flexibility. With fewer mechanically driven components, manufacturers can optimize vehicle layouts for better aerodynamics and weight distribution, further improving energy efficiency.

Supporting Mild Hybridization

One of the most promising applications of 48V technology is its role in mild hybrid systems. Unlike full hybrid or battery-electric vehicles, mild hybrids use a smaller battery and an integrated starter-generator to capture and reuse energy that would otherwise be lost. This stored energy can then be used to assist with acceleration, enable engine-off coasting, and improve start-stop functionality, all of which contribute to lower fuel consumption and emissions.

Mild hybrid systems are particularly beneficial for commercial vehicles, where engine efficiency is crucial for long-haul operations. By ensuring the engine runs at optimal efficiency, 48V mild hybrid technology helps reduce overall operating costs while supporting the industry’s broader move toward electrification.

Enhancing Emissions Control Technologies

Eaton’s 48V supercapacitors are able to quickly charge and discharge at higher rates than lithium-ion batteries. (Image: Eaton)

A major hurdle in reducing vehicle emissions is maintaining the effectiveness of aftertreatment systems, particularly in diesel-powered commercial vehicles. These systems rely on high operating temperatures to break down pollutants effectively. However, during startup and low-load driving conditions, aftertreatment components can fall below their optimal temperature range, reducing their efficiency.

A 48V electrical system enables electrical system enables electrical system enables the integration of electrified heaters that quickly warm the after-treatment catalyst, ensuring it functions efficiently even in suboptimal conditions. By maintaining ideal operating temperatures, this technology significantly improves emissions control, helping vehicles meet new performance expectations while maintaining compliance with evolving standards.

As demand for more efficient and cleaner commercial vehicles continues to grow, companies with experience in low-, medium-, and high-voltage power management, like Eaton, can help manufacturers integrate advanced electrical architectures that support the industry’s ongoing transition toward greater efficiency and sustainability.

The Future of 48V Electrical Systems in Commercial Vehicles

The shift to 48V electrical systems represents a significant step forward in modernizing commercial vehicle powertrains. As manufacturers continue to seek ways to improve efficiency, reduce operating costs, and meet evolving industry expectations, 48V architectures will play an increasingly vital role in shaping the future of transportation.

The 48V mild hybrid is an electronically regenerative accessory drive ideal for commercial vehicle applications. As an integrated solution, the 48V mild hybrid features a 48V motor generator that connects to the PTO opening on an automated manual transmission. The motor generator replaces the alternator to charge the battery and powers an electric air conditioning compressor. The regenerative system can power components with the engine off, reducing emissions and saving fuel. It’s a flexible solution providing both 48V and 12V to run accessories. (Image: Eaton)

Key trends driving this transition include:

Increased electrification of components – Moving away from mechanically driven accessories improves efficiency, reduces wear and tear, and simplifies vehicle maintenance.
Adoption of mild hybrid technology – Capturing and reusing energy that would otherwise be lost offers an accessible way to enhance fuel efficiency and reduce emissions.
Advancements in power electronics – As electrical systems become more sophisticated, 48V technology provides the foundation for smarter energy management and enhanced vehicle functionality.
Integration with emerging vehicle technologies – As autonomous and connected vehicle systems grow more complex, the demand for reliable, high-power electrical architectures will continue to increase.

For fleet operators and vehicle manufacturers, transitioning to 48V electrical systems is a strategic investment in long-term sustainability and performance. These systems not only improve fuel efficiency and reduce emissions but also provide the flexibility needed to adapt to future advancements in commercial vehicle technology.

The commercial vehicle industry is evolving, and with it, the need for smarter, more efficient power management solutions. New 48V electrical systems are emerging as a key technology in this transformation, offering significant advantages in efficiency, emissions reduction, and overall vehicle performance.

Power Solutions

In 2023, Eaton announced its first agreement with a global OEM to supply its 48V programmable aftertreatment heater controller for electrically heated catalysts. At the time, Eaton said its family of electric heater power electronics controllers were being developed for solutions between 2 kW and 15 kW of power and that they operate with up to 99 percent peak efficiency.

The company said the controller was designed to receive power commands from the aftertreatment system and diagnostic feedback of the heater element and to provide soft-start and stop capabilities for assisting in maintaining system voltage control.

With the continued evolution of commercial vehicle design and electrification, 48V systems will remain a vital tool in optimizing performance and ensuring that fleets remain competitive in an ever-changing landscape.

This article was written by Ben Karrer, Head of Engineering, Low Voltage & Power Conversion, eMobility Division, Eaton Mobility Group (Southfield, MI). For more information, visit here .