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How Ultracapacitor Engine Starting Can Help Truck Drivers Comply with Anti-Idling Laws

How Ultracapacitor Engine Starting Can Help Truck Drivers Comply with Anti-Idling Laws

| Jeff Brakley, Senior Business Portfolio Manager – Truck
Truck drivers across the United States face hefty fines if they leave their trucks idling. States are enacting anti-idling laws to lessen the effects of diesel emissions on the environment and public health.

Idling TrucksThese anti-idling laws are a new challenge for truck drivers who idle their trucks for a variety of reasons, including to run heating or cooling, and to ensure that they can get the truck started. The whole reason for idling the truck is to avoid the batteries from dying and being unable to start the truck. Trucks with battery-based auxiliary power units (APUs) are going to have a more difficult time complying with anti-idling laws. It’s almost a lose-lose situation: Risk getting a fine by idling the truck to avoid the need for a jump-start or to recharge the batteries, or turn the truck off to comply with the law, but risk not being able to start the truck and falling behind on delivery schedule. At the 2015 Mid-America Trucking Show (MATS) in Louisville, KY, many drivers also told me they are now required to turn off their engines while waiting in line at weigh stations, further challenging their batteries.

What if I told you that you could replace one battery with a Maxwell Engine Start Module (ESM), which is ultracapacitor-based technology, and have no problems turning your truck off and on to comply with anti-idling laws?

Ultracapacitors are used to start the truck—they take that responsibility away from the batteries so that the truck can use the battery energy for other loads. One Group 31 sized Engine Start Module easily cranks diesel engines up to 16 liters in displacement. Operators can now avoid idling with the assurance that the ESM will crank the engine, even if the other batteries are partially discharged. With the ESM, you can turn your truck off and on as much as you need to throughout your day to comply with anti-idling laws. The other truck batteries can also be replaced with deep cycling or absorbed glass mat (AGM) batteries that have long reserve capacity minutes. You don’t need high cold cranking amp (CCA) batteries with the ESM installed.

You might be thinking: How is the ESM so dependable for turning on the truck? That’s the great thing about ultracapacitor technology—it’s all about power. Batteries have high energy density, and low power density. Ultracapacitors are the opposite—they have low energy density but high power density.

Ultracapacitors resolve truck drivers’ dilemma with anti-idling laws. Trucks that are retrofitted with ultracapacitor engine starting technology will have dependable, stress-free engine starting, allowing truck drivers to comply with anti-idling laws.

The Costs of Truck Idling

  • Fees incurred by anti-idle regulation enforcement
  • Money lost on spent fuel
  • Engine wear-and-tear
  • More frequent oil and filter changes
  • Replacement of components, including alternators, fan clutches, thermostats, water pumps and belts
  • Lower battery life
Learn more: Long-Haul Truck Idling Burns Up Profits, U.S. Department of Energy

Avoid the costs of idling! To learn more about ultracapacitor-based engine starting, visit Maxwell’s Engine Start Module page or email

Priya BendaleJeff Brakley
Senior Business Portfolio Manager – Truck
About this author

Jeff Brakley is Senior Business Portfolio Manager for Maxwell’s truck unit and has contributed to the development of the Engine Start Module (ESM) from its inception. He is a member of SAE International and an Associate Corporate member of the American Trucking Associations (ATA) and the Technology & Maintenance Council (TMC). Jeff serves on the S.1 Electrical & Instruments Task Force, and recently contributed to the SAE J3053 Task Force to develop the Heavy Duty Truck Electrical Circuit Performance Requirement for 12/24 Volt Electric Start Motors Recommended Practice.

Throughout his 30-year career, Jeff has held both engineering management and program management positions for several leading national defense contractors and commercial companies, including General Dynamics, Martin Marietta, L3 Communications and Ametek Programmable Power. Jeff holds a Bachelor of Science in engineering from Purdue University and an MBA in technology management from the University of Phoenix.

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