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Stop-start vehicles a better energy strategy than full EVs

Praise the full electric vehicles (EV) for their coolness and potential to be fully green, but not potential to empty your pocketbook of its green dollars. Instead, stop-start vehicle technology will likely outperform, outsell and kick every EV in the rear bumper.

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Full EVs are not ready for prime time, especially in the area of affordability like the Ford Focus Electric. Washington can throw all the money it wants at EV technology, but in no way can it ever sustain it. In the long run, EV technology must stand on its own; and right now it is simply too expensive.

Witness what Ford did by placing a $40k price tag on its Focus Electric, while the Chevy Volt is $42k with a range extender engine, and the Nissan LEAF is at the lowest end at $32.2K. All are counting on government subsidies to support sales. Imagine what happens when that ends.

Now consider that stop-start vehicles (SSV) are already outselling hybrids; and, according to Pike Research, by a factor of 3.5 to 1. Furthermore, the SSVs are expected to widen to 16 to 1 over the next few years. Main reasons: low cost and ease of integration.

So does that mean electrification is a dead issue? Absolutely not! SSV requires electrification, just not in an expensive way. This means the electrification of the automobile has only just begun; in other words, it’s just starting out better in the mild form of SSV.

Think about it: SSV systems have the potential to save more gasoline simply due to volume; and isn't that one of the nation's energy goals? Truth is, SSVs emerge within a mild hybrid format that is far less expensive and in far greater numbers than full EV lovers can ever imagine.

In a dynamic article by entitled, Is Stop-start Idle Elimination Crushing Vehicle Electrification? John Petersen, the author writes, “stop-start idle elimination will become a dominant automotive fuel efficiency technology by mid-decade.”

I don't know if it's crushing the EV industry to the point where it will go away, but I have to agree with his assessment about SSV dominance. Think about it: the goal is to save gasoline, reduce imported oil, reduce pollution and make it so affordable that an average wage earner can buy one. Nowhere is that more probable than with an SSV system, especially coupled to a split-cycle engine.

My visit last week to The Battery Show 2011 that was adjacent to the Engine Expo is a case in point. The supporting modules of Controlled Power Technologies alone proved beyond shadow of doubt that the IC engine is not going away anytime soon; neither does it have to. In fact, it is within the coordination with the IC engine that stop-start, electric turbo and electric power regeneration are making such gains at a cost that all will likely afford. Read: Controlled Power Technologies reveals modular hybridization solutions at Engine Expo 2011

Think Energy Systems Synergies

Now couple those technologies with the latest in battery achievements and you begin to really see major system synergies taking place,

For the record, stop-start technology enables an engine to automatically turn off when your car isn't moving. For the record, an engine that shuts down also shuts down its pollution capability while it is shut down.

It then instantly restarts the engine the moment you take your foot off the brake. Of course, it’s a polluter at that point, but low displacement engines with turbo power have proven to reduce CO2 and meet 2016 standards, and will likely beat 2025 standards as engines improve; and especially if the industry adopts HCCI and split-cycle technology.

The biggest problem with stop-start, though, is that it's a battery power eater; that is, a standard lead-acid battery fails, because present batteries cannot take the constant drain and recharge sequence, also called duty cycles.

Reason is, instead of just starting the engine to begin a trip, it has to start the engine several times during the trip, plus carry accessory loads during engine-off intervals and then recover its charge very quickly to prepare for the next engine off opportunity.

Some OEMs are opting for small lithium-ion batteries like the Buick eAssist™, but that is still on the expensive side. Instead, latest thinking is to use ultra-capacitors, such as those developed by Maxwell and others. These are capable of fast storage and fast outflow of electrons.

Then there is the latest in nano-scale cathode materials, which has much higher energy density, yet avails faster charging, recovery and power output than standard batteries, plus at a very reasonable cost that does not require an entire remake of the battery industry’s manufacturing line.

Wait There’s More

I must remind you that that IC engine has another major evolutionary step in its future; and it’s called split cycle. By splitting the four-cycle Otto engine in half, thereby creating a cold and hot side, efficiency gains can be raised from the present 30-percent to 50-percent and up.

Now, lest you fear that split cycle engines will overshadow electrification, think again. Sure, split cycles have an air hybrid capability, but all of the present engine technologies like multi-valves, variable valves, variable cams and multi-turbos can still be used. But here’s the real gain: Split cycle engines can also take advantage of stop-start, electric turbos and especially electrical regeneration if no other reason than support of onboard electrical systems when the engine is shut down.

So, praise all you want about the capabilities of full electric vehicles (EV) but I still say they are not ready for prime time, especially in the area of affordability. Instead, stop-start technology has the greatest potential to bring electrification to the masses in a manner they can afford.

About the Reporter: After 39 years in the auto industry as a design engineer, Frank Sherosky now trades stocks, futures and writes articles, books and ebooks like, "Perfecting Corporate Character," "Awaken Your Speculator Mind", and "Millennial World Order" via He may be contacted here by email: [email protected] and followed in Twitter under @Authorfranks

Additional Reading:
The Battery Show 2011 Message: Many forms of intelligent energy management
Lotus Engineering wows Battery Show 2011 with synthetic-sound technology
The Business of Plugging In 2011: Media drives EVs at Ride and Drive
Tech synergies permeating IC engine development per 2011 DEER Conference
Bongiovi Acoustics brings cinema sound to autos at 2011 Detroit Auto Show

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Anonymous (not verified)    November 4, 2011 - 12:47PM

How can you even compare SSV, hybrids, and full electric vehicle, in terms of sales?

Your article is not even comparing benefits/drambacks of each technology, but there is a easy reason for that: SSV don't bring anything relevant enough to the problematic of CO2 emissions reduction.

This is poor journalism.

Frank Sherosky    November 4, 2011 - 2:46PM

In reply to by Anonymous (not verified)

With all respect, do your homework. An engine that shuts off has zero emissions! A high volume of cars with this technology and lower engine size contributes far less CO2 than you realize; as the limited volume of full EVs is a major factor, which, by the way, get their recharging most likely from coal-powered plants. Get the volume of EVs up then maybe you have an argument, except for that coal link.

Every government study says full EVs won't get past 15% of total volume even by 2030. And there's a simple reason: they cost too much!

Mark (not verified)    November 8, 2011 - 1:59PM

Having bought a new 2008 Malibu Hybrid, one of very few vehicles available with engine stop-start technology, I am certain that people driving these in a city environment will save a little money on fuel and lower the emissions a little as well.

On the other hand, in mixed driving, the car got no better mileage than the standard 4 cylinder Malibu because Chevrolet put a 6 speed automatic in all the Mailbu's except the Hybrid, which got the 4 speed automatic. Overall, I drove it for 9 months and traded it for a subcompact car that gets far better fuel economy.