NVH issues with stopstart systems must be overcome Densorsquos Martin says

NVH issues with stop/start systems must be overcome, Denso’s Martin says.

Stop-Start Technology Faces Uphill Battle in North America

Americans are slow to embrace the fuel-saving technology because of perceived noise, vibration and harshness issues and the fact that systems originally designed for Europe shut down the air conditioner during stops. 


DETROIT – Stop/start technology has been slow to gain a foothold in North America and likely will take another several years before it reaches the popularity it enjoys in Europe and Asia-Pacific region, a panel of industry experts says at the 2013 SAE World Congress here.

The U.S. penetration rate for light-vehicle stop/start systems is just 1%, and most are found in hybrid-electric vehicles. In Europe, where gasoline hovers at about $8 a gallon, 40%-50% of all LVs feature the technology.

Mark Rakoski, executive director-sales and engineering at Mitsubishi Electric Automotive America, says the auto maker first introduced stop/start in 1995. But it soon dropped the technology due to underwhelming demand and low gas prices.

While relatively few North American consumers care much about stop/start, there are good reasons auto makers are planning to debut such systems here. “The biggest factor is global emissions standards,” he says.

Rakoski says 10 million stop/start systems are sold annually on a global basis, and that number is expected to rise to 40 million by 2020, when North America is predicted to have a 60% penetration rate.

His fellow panelists expect two types of stop/start systems to dominate the market. One is a belt-starter generator that typically results in a 5%-6% fuel-economy savings, depending on driving conditions.  The second system is a reinforced starter, which allows for a higher number of cranks but only achieves a 3%-4% improvement.

Michael Forissier, marketing, research and development director-Valeo Powertrain Systems, says the supplier developed a belt-starter generator in 2004 and introduced a reinforced starter in 2009.

He says most of the demand for stop/start is in Europe and Japan, with limited use in the U.S. despite the fuel-economy savings and emission-reductions the system brings.

Americans are slow to embrace stop/start because of perceived noise, vibration and harshness issues and the fact that systems originally designed for Europe shut down the air conditioner during stops.

To keep the air conditioning running, Valeo developed an electric compressor that runs independently of the engine and an oil-pressure buffer that keeps automatic transmissions, which Americans prefer, pressurized during stops for fast restarts.

“Our forecast for America is (stop/start) will first start in entry-level segments,” he says. “And in America, we (still) see slower growth than in Europe.”

Robert Martin, director-engine control group, Denso, lists several reasons that could cause stop/start systems to fail in North America and others that could lead to its success.

NVH issues are a negative, he says, as is price, skepticism and perceived inconvenience by consumers. Those who consider stop/start a positive technology cite environmental benefits, cost savings and ease of use.

“If the system is creating anxiety, it will struggle, and if it saves money it will have a chance of success,” he says. “Attitudes and perceptions are all over the map, so the industry has a tough job ahead.”

Educating American consumers on the benefits of stop/start technology is essential to its success here, says Scott Dahl, regional president-starters, motors and generators division, Bosch.

Auto makers are pushing the technology for the emission-reduction and fuel-economy savings it provides in the face of looming governmental regulations. But that dynamic must change, he says. “We need to change from a legislative push to an end-user pull.”

Dahl says a well-executed stop/start system is essential in North America to gain market acceptance and to provide even more benefits.

He suggests an industry wide collaboration to educate North American consumers on the benefits of the technology, as was done when electronic-stability control debuted more than a decade ago.

“We need to focus on a transparent system and educate consumers on how it operates and teach the benefits in real-world driving,” Dahl says. “Are consumers interested in the technology? If (they are) educated, yes.”

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