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BPHannes · 04-08-2012, 02:03 PM

@jmcc

Thanks for the tip, are you talking about the Clean and Cool Mission 2012? May I ask what other technologies you are applying?

@pete

We've done user research to figure out why these systems aren't as widely spread as they could be and the result so far is that

1) Fuel savings are not high enough to make a difference for the average driver

This of course depends heavily on traffic situation and driving style. Many new car models come with micro hybrid functions as a standard (especially in Europe; unlike in the US full hybrids are less common and micro/mild hybrids more), so the buyers can't really chose whether they want to have it or not. Those who can choose often go without it; those who can't often decide to deactivate it (either because they believe that car parts get damaged or because they are annoyed by the constant start and stop).

2) The functionality is limited by the battery

In many cases, the capacity is not high enough to ensure a proper functioning of the start/stop mechanism. E.g. when air condition, radio, etc. are switched on, the engine has to restart to maintain the charging level. Also, many drivers reported that the function stops working completely when the battery reaches an age of 2-3 years. Besides that, there are also issues with the ibs (intelligent battery sensor), which provides faulty capacity levels and hinders the start/stop function.

3) There are concerns about the maturity of the technology

Mostly these concerns are about the reliability of the system. In low outside temperatures (below 3° C/37° F) and in warm temperatures where the AC is on, the start/stop automatic doesn’t work. There are a number of factors that influence the functioning and drivers are not informed about them, which is why some of them deactivate the system permanently. Other problems regard the speed of restarting the engine, which is perceived as too slow by some.

4) The usability is limited

In certain traffic situations there is no added benefit. This is particularly true in traffic jams where periods of standstill are short and the constant stop and start becomes annoying. Some manufactures counteract these issues by requiring the car to exceed a certain speed before the mechanism is reactivated. Also, drivers in rural areas don’t experience stop-and-go traffic and can therefore not realize fuel savings.

5) Drivers are concerned about faster deterioration of car parts

Many drivers don’t trust micro/mild hybrid systems because they expect a faster deterioration of parts like alternator, starter motor and engine due to the considerably higher frequency of starts. Whether this is justified is difficult to say. We have heard different opinions on that; e.g. increased wear doesn’t seem to be a problem for the Toyota Prius, however some manufacturers stated that conclusions can only be made after the car has been used for a longer period.

All these concerns are of a technical nature and in order to achieve a higher technology diffusion of micro/mild hybrids, they have to be tackled. There are several approaches to do that (e.g. upgrading the technology to allow short-distance electric drive, making it possible to recharge the battery externally, pre-heating the engine, etc.), however the additional cost of such approaches must be weighed against the benefits.

What do you think about these issues? Can you think of ways to counteract them? There are countless other technologies that aim at the same goal of reducing fuel consumption and emissions. The big question is which one is most promising and how different technologies can be combined to achieve a significant improvement.

04-08-2012, 02:03 PM	#4 (permalink)
BPHannes EcoModding Lurker Join Date: Apr 2012 Location: Vienna Posts: 6 Thanks: 0 Thanked 0 Times in 0 Posts	@jmcc Thanks for the tip, are you talking about the Clean and Cool Mission 2012? May I ask what other technologies you are applying? @pete We've done user research to figure out why these systems aren't as widely spread as they could be and the result so far is that 1) Fuel savings are not high enough to make a difference for the average driver This of course depends heavily on traffic situation and driving style. Many new car models come with micro hybrid functions as a standard (especially in Europe; unlike in the US full hybrids are less common and micro/mild hybrids more), so the buyers can't really chose whether they want to have it or not. Those who can choose often go without it; those who can't often decide to deactivate it (either because they believe that car parts get damaged or because they are annoyed by the constant start and stop). 2) The functionality is limited by the battery In many cases, the capacity is not high enough to ensure a proper functioning of the start/stop mechanism. E.g. when air condition, radio, etc. are switched on, the engine has to restart to maintain the charging level. Also, many drivers reported that the function stops working completely when the battery reaches an age of 2-3 years. Besides that, there are also issues with the ibs (intelligent battery sensor), which provides faulty capacity levels and hinders the start/stop function. 3) There are concerns about the maturity of the technology Mostly these concerns are about the reliability of the system. In low outside temperatures (below 3° C/37° F) and in warm temperatures where the AC is on, the start/stop automatic doesn’t work. There are a number of factors that influence the functioning and drivers are not informed about them, which is why some of them deactivate the system permanently. Other problems regard the speed of restarting the engine, which is perceived as too slow by some. 4) The usability is limited In certain traffic situations there is no added benefit. This is particularly true in traffic jams where periods of standstill are short and the constant stop and start becomes annoying. Some manufactures counteract these issues by requiring the car to exceed a certain speed before the mechanism is reactivated. Also, drivers in rural areas don’t experience stop-and-go traffic and can therefore not realize fuel savings. 5) Drivers are concerned about faster deterioration of car parts Many drivers don’t trust micro/mild hybrid systems because they expect a faster deterioration of parts like alternator, starter motor and engine due to the considerably higher frequency of starts. Whether this is justified is difficult to say. We have heard different opinions on that; e.g. increased wear doesn’t seem to be a problem for the Toyota Prius, however some manufacturers stated that conclusions can only be made after the car has been used for a longer period. All these concerns are of a technical nature and in order to achieve a higher technology diffusion of micro/mild hybrids, they have to be tackled. There are several approaches to do that (e.g. upgrading the technology to allow short-distance electric drive, making it possible to recharge the battery externally, pre-heating the engine, etc.), however the additional cost of such approaches must be weighed against the benefits. What do you think about these issues? Can you think of ways to counteract them? There are countless other technologies that aim at the same goal of reducing fuel consumption and emissions. The big question is which one is most promising and how different technologies can be combined to achieve a significant improvement.