End of the line for start-stop? usa agency to scrap fuel-saving feature

Start-stop technology facing demise in usa

for years, the start-stop system has been touted as a key tool for reducing vehicle emissions and improving fuel efficiency. however, a recent decision by the environmental protection agency (epa)signals a potential end to its widespread use, particularly in the united states. the move, part of the repeal of the 2009 obama epa endangerment finding, effectively ends the off-cycle credits that incentivized its adoption. this isn't a new development; the epa has been considering phasing out the feature for some time.

A brief history of start-stop

the concept of automatically shutting off the engine when idling isn't new. it emerged in the 1970s and 1980s, but gained traction in the mid-2000s with the implementation of euro5 emissions standards. the Technology's primary goal is to reduce fuel consumption and, consequently, emissions, especially in urban environments. studies suggest potential fuel savings of up to 5% in dense traffic. however, this efficiency comes at a cost, raising questions about long-term engine and battery health.

The cost of saving fuel

while the potential fuel savings are appealing, the start-stop system places significant strain on the starter motor and battery. the battery, in particular, requires a higher capacity and often utilizes agm (absorbed glass mat) or efb (enhanced flooded battery)Technology to withstand the increased charge-discharge cycles. this leads to a shorter lifespan, typically between three and five years, depending on driving habits. frequent stop-and-go city driving accelerates battery wear.

Problems and drawbacks

beyond battery life, the start-stop system has been linked to other issues. the puretech engine from psa (now stellantis) provides a notable example. originally problem-free, the engine experienced issues later on when combined with particulate filters required for euro6 emissions standards. a design flaw led to fuel leaking into the oil, causing significant damage. while the start-stop system itself may not directly cause this, it exacerbates the stress on the engine and related components.

User frustration and disabling the system

many drivers have resorted to disabling the start-stop system altogether to avoid potential problems. while some vehicles offer a simple button to deactivate the feature, others require navigating through menus. this manual intervention defeats the purpose of automatic fuel savings and adds to the complexity of vehicle maintenance. the hassle of disabling the system each time a vehicle is used is a significant deterrent for many.

Epa's decision and future implications

the epa's decision to end off-cycle credits for start-stop Technology reflects a growing skepticism about its overall value. lee zeldin, the current administrator of the agency, openly criticized the system, calling it a