John Wathen, Senior Applications Engineer at Inventus Power, delivered a presentation on leveraging lithium battery technology to revolutionize vehicle ancillary equipment systems (AES) as part of the Future of Electrification conference.
The Imperative for Ancillary Electrification
The adoption of battery-powered AES is largely driven by the urgent need to address global emissions. The transportation sector contributes 29% of global CO2 emissions, with medium and heavy-duty trucks responsible for a significant portion. Wathen calculated that approximately 2 to 3% of global CO2 emissions annually - equating to 0.8 to 1.2 billion metric tons - originate from medium to heavy-duty trucks utilizing ancillary equipment.
Wathen emphasized that full vehicle electrification in this sector faces immense challenges; for instance, electrifying a garbage truck requires a battery pack weighing over 4,000kg (8,800lbs), which is the weight of an empty shipping container. Consequently, the most practical and efficient solution in the current state is the electrification of the ancillary systems alone.
Applications and Core Benefits
AES target small to midsize vehicles and systems requiring power for hydraulic pumps, vacuums, compressors, and actuators. Applications range from refuse collection and bucket trucks to refrigerated trailers and cement mixers. Key benefits realized across these applications include idle reduction or elimination, as the primary engine no longer needs to run to power auxiliary functions when the vehicle is stationary.
The shift to electric AES delivers substantial benefits, including regulatory compliance (driven by the European Commission, EPA, and others) and crucial operational improvements. Electrifying the AES of a medium/heavy-duty truck can account for a 30% CO2 emissions reduction for that vehicle. Wathen highlighted that noise reduction is a critical non-environmental benefit, improving residential quality and significantly enhancing operator safety by reducing the need for intense hearing protection. Furthermore, the total cost of ownership (TCO) is lowered by decreased maintenance requirements, as electric motors have fewer moving parts than conventional systems. Inventus Power sees the first wave of adoption in the construction, lawn and garden/outdoor power equipment, and refrigerated truck industries.
Electrification Conversion Paths
Wathen outlined various integration types for AES:
- Independent Electric Ancillary System: Low integration solutions, such as trailerable equipment, which are modular, flexible, and easily certified.
- Directly Integrated System: Medium integration where the system is permanently bolted onto the vehicle chassis (e.g., a garbage truck side loader), making it a prime candidate for noise reduction.
- Mechanical Hybrid System: High integration, offering the flexibility to switch between the vehicle’s powertrain and the electric power system. This is ideal for applications requiring high, short-duration peak loads, for instance, starting a concrete mixer drum.
The technological conversion path includes transitioning to fully electric actuators, which provide precision, repeatability, and eliminate hydraulic fluid requirements. For existing hydraulic systems, Electric Power Take-Off (EPTO) solutions using electric pump motor systems allow for simple retrofitting, providing on-demand and variable-speed pressure. Modern motor control systems, such as those from ZAPI Group, enable soft start capabilities, crucial for protecting the lithium-ion battery management system (BMS) from inrush current.
Challenges and Lithium Advantages
While the benefits are clear, challenges remain, including the lack of full standardization across mobile machine connections and the difficulty of properly rightsizing the battery system to meet diverse duty cycles. Wathen stressed that lithium-ion technology is superior to lead-acid for these systems because it offers a higher ROI due to a greater cycle life, significantly lower maintenance (no watering or manual balancing required), and more integrated intelligence within the battery system.
Finally, Wathen noted that adopting an electrified platform greatly facilitates Internet of Things (IoT) capabilities, allowing for fleet insights, predictive maintenance scheduling, and real-time field diagnostics that boost operational efficiency.
To see the full presentation, please watch the on-demand video below: