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#121
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In article >, "FanJet" > wrote:
>Really depends on where and how you're driving, doesn't it? No doubt the HX >equals or bests the hybrid in some circumstances. In the end, it takes 745.7 >Watts for each horsepower generated by a hybrid - completely ignoring >losses. Except for the small amount generated by regenerative braking, the >rest comes from gasoline. Regen braking can, in theory, recover about 30-40% of the energy used on the EPA city cycle. In reality, with losses it is probably more like 10-15% increase in fuel economy. A hybrid also allows the designer to readily shut the engine off on idle. In theory, you could do this with any engine and just use the 12V+starter to get it going again. Practically, no one does this. I suppose for drivability, NVH, and maybe starter motor wear issues. A hybrid also allows you to run closer to the sweet spot of the engine. For example, a gasoline ICE maxes out at about 35% thermal efficiency. But in the normal driving load & rpm, it is more like 20%. By running at a higher load, where it is more efficient, than required. And feeding this to the battery. Then subsequently running at virtually no load, and letting the battery+motor run the vehicle, the average ICE operating efficiency is increased. Last, a hybrid allows downsizing the engine without sacrificing performance. A smaller engine runs at an average higher load, where (see above) it is more efficient. So I'd say there are 4 solid reasons why a hybrid can return better fuel economy. Certainly there are minuses (cost, weight, complexity), and yes, the real-world gains never seem to match the advertised EPA numbers. |
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#122
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Gordon McGrew wrote:
> On Wed, 03 Aug 2005 20:30:50 GMT, "FanJet" > > wrote: > >> Gordon McGrew wrote: >>> On Tue, 02 Aug 2005 13:23:34 -0700, (Jason) wrote: > >>>> Hello, >>>> I disagree. The so called "greenies" love the word "hybrid" since >>>> they love to tell their friends and almost anyone else that they >>>> talk to that they have a "hybrid". They also like it when fellow >>>> greenies see the word "hybrid" on the back of their cars." It's not >>>> the actual word that they love--it's the thought behind the word. >>>> An example is the word "diamond". It's the thought behind the word >>>> that is important when it comes to "hybrid" or "diamond". >>> >>>> Jason >>> >>> Well it may be a matter of semantics but the way I see it, they are >>> bragging the technology and benefits of the hybrid, not the word >>> itself. I think most of them understand the technology reasonably >>> well. It would be a different story if they had no real clue what >>> 'hybrid' meant, or if hybrid technology didn't really do anything. >>> Think Fahrfurnugen or Cab-Forward design. Got a Hemi in that thing? >> >> I was talking with a proud Prius owner just the other day. She was >> very pleased with her new car just as I am when I have a new >> vehicle. She showed me all the screens and even cranked on the A/C >> pointing out that it worked even when the car wasn't started. Very >> nice lady and a friend but in my experience, a typical hybrid owner. >> The point is that her A/C isn't working just because the >> heat-exchanger fan motor is running and, most importantly, her car >> is entirely powered by gasoline - just like mine. Sure her car is a >> bit more efficient using techniques such as regenerative braking but >> these could be put to use on my car too. The real reason her car is >> more efficient than mine has nothing to do with batteries or >> electric motors but is the direct result of the computer control >> system and an advanced gasoline engine. Naturally, both could be >> used on my car too. > > Really? Don't all cars have advanced engines and computer control > these days? I am not aware of any particular advancements in the > Prius' gasoline motor which would explain it's exceptional fuel > economy. The computer only improves economy because it has a battery > and motor to control. If manufacturers could get the same benefit > without these expensive parts, why don't they do it? The fact is that > the most advanced gas engine with computer control cannot match this > efficiency level, at least not with acceptable performance. No, the fact is, with the exception of a truly minor assist from regenerative braking, the hybrid's only source of energy is gasoline - just like a non-hybrid. The comparison becomes even more interesting when you consider that the regenerative braking assist is rendered less significant because the hybrid is required to carry the extra weight associated with the extra electrics/electronics. Then, there's the losses associated with mechanical > electrical > electrical > mechanical and all the way back for regenerative braking (maybe less the dc > ac conversion). Just doesn't add up. And, there 's more to the story too. The performance boost you're referring to is only there for a brief period of time. Soon the batteries need a charge and the ICE isn't powerful enough to fully charge the batteries and simultaneously power the car so, it mostly powers the car. There is no free lunch. >> So, when you think >> current hybrid, you should think Fahrfurnugen, Cab-Forward design or >> hemi. You might also throw in extra profits & CAFE. > > I thought everyone was saying that the manufacturers are losing money > on hybrids. As for CAFE, it wouldn't help your CAFE if it didn't > improve milage. Not sure what everyone else is saying but I can tell you for sure that the car makers aren't philanthropic organizations. Nearly all of them improved CAFE figures by simply insisting that everyone use 5W20 weight motor oil. The manufacturers didn't charge a thing and, other than adjusting documentation, it didn't cost them a anything either. |
#123
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Bebop wrote:
> FanJet > wrote: > >> Bebop wrote: >>> > wrote: >>> >>>> I would stay away from hybrids. Saw one die in the middle of >>>> traffic - no power and creating massive backups. The industry will >>>> eventually go to hydrogen systems, but never electric. >>> >>> The hybrid is not true electric, thus the word "hybrid". >> >> Actually, they're true gasoline since that's their *only* power >> source. "Hybrid" is a spin that gets people to purchase something >> they otherwise wouldn't. > > > Not excatly, you can run the car on battery alone. But you will not > get far on it. Some people have managed to alter the program on the > car's CPU and allows it to run longer on battery and recharge it at > night to get better mileage. How do they recharge it at night? > A true gasoline car of the same displacment will not get that kind of > mileage, but a hybrid will. The Prius and the Honda hybrid have only one external energy source which is gasoline. |
#124
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On Sat, 06 Aug 2005 04:21:09 GMT, "FanJet" >
wrote: >Gordon McGrew wrote: >> On Wed, 03 Aug 2005 20:30:50 GMT, "FanJet" > >> wrote: >> >>> Gordon McGrew wrote: >> Really? Don't all cars have advanced engines and computer control >> these days? I am not aware of any particular advancements in the >> Prius' gasoline motor which would explain it's exceptional fuel >> economy. The computer only improves economy because it has a battery >> and motor to control. If manufacturers could get the same benefit >> without these expensive parts, why don't they do it? The fact is that >> the most advanced gas engine with computer control cannot match this >> efficiency level, at least not with acceptable performance. > >No, the fact is, with the exception of a truly minor assist from >regenerative braking, the hybrid's only source of energy is gasoline - just >like a non-hybrid. What did I say that would lead anyone to believe otherwise? The issue is how the hybrid system improves the efficiency of conversion of gasoline to kinetic energy. Saying that the only source of energy is gasoline is a red herring. Actually, the only source of energy is the Sun. Mother Nature just converted a portion of the solar energy to oil for our convenience. >The comparison becomes even more interesting when you >consider that the regenerative braking assist is rendered less significant >because the hybrid is required to carry the extra weight associated with the >extra electrics/electronics. Then, there's the losses associated with >mechanical > electrical > electrical > mechanical and all the way back for >regenerative braking (maybe less the dc > ac conversion). Just doesn't add >up. Of course, any conversion from one kind of energy to another involves inefficiencies. Merely listing them out says nothing about the overall efficiency of the system. Honda did use regenerative braking of a sort on a Civic model about 15 years ago. The computer would only allow the alternator to supply power when the vehicle was decelerating (or if the battery charge dropped too low.) It's benefit was pretty small. Diesel locomotives drive generators which power electric motors which move the train. Why not just have the diesel engine turn the wheels directly? Because the use of electric conversion is more efficient overall, even though the extra conversion involves a loss of energy. The railroad companies don't buy diesel-electric locomotives so they can brag about driving a hybrid. And all the energy comes form diesel oil. > And, there 's more to the story too. The performance boost you're >referring to is only there for a brief period of time. Soon the batteries >need a charge and the ICE isn't powerful enough to fully charge the >batteries and simultaneously power the car so, it mostly powers the car. >There is no free lunch. You seem to believe that everyone who buys a hybrid thinks he owns a perpetual motion machine. The fact is that the performance boost is only needed for a short time. Most car engines spend only 1% of their working hours producing their rated horsepower. There is lots of extra capacity for charging the batteries. Other posters have listed numerous reasons why hybrid systems increase efficiency. It could be all academic except that hybrid cars are at the top of the chart for high-milage gasoline road cars. >>> So, when you think >>> current hybrid, you should think Fahrfurnugen, Cab-Forward design or >>> hemi. You might also throw in extra profits & CAFE. >> >> I thought everyone was saying that the manufacturers are losing money >> on hybrids. As for CAFE, it wouldn't help your CAFE if it didn't >> improve milage. > >Not sure what everyone else is saying but I can tell you for sure that the >car makers aren't philanthropic organizations. Nearly all of them improved >CAFE figures by simply insisting that everyone use 5W20 weight motor oil. >The manufacturers didn't charge a thing and, other than adjusting >documentation, it didn't cost them a anything either. And it didn't provide much benefit either. Can you point to any cars which increased their EPA milage ratings by even 1 mpg as a result of switching to lighter oil? |
#125
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On Sat, 06 Aug 2005 04:27:14 GMT, "FanJet" >
wrote: >Bebop wrote: >> FanJet > wrote: >> >>> Bebop wrote: >>>> > wrote: >>>> >>>>> I would stay away from hybrids. Saw one die in the middle of >>>>> traffic - no power and creating massive backups. The industry will >>>>> eventually go to hydrogen systems, but never electric. >>>> >>>> The hybrid is not true electric, thus the word "hybrid". >>> >>> Actually, they're true gasoline since that's their *only* power >>> source. "Hybrid" is a spin that gets people to purchase something >>> they otherwise wouldn't. >> >> >> Not excatly, you can run the car on battery alone. But you will not >> get far on it. Some people have managed to alter the program on the >> car's CPU and allows it to run longer on battery and recharge it at >> night to get better mileage. > >How do they recharge it at night? They have retrofitted a line voltage charging system, an option available only if you have a hybrid system to start with. Manufacturers are considering adding this as standard equipment to their hybrid vehicles. > >> A true gasoline car of the same displacment will not get that kind of >> mileage, but a hybrid will. > >The Prius and the Honda hybrid have only one external energy source which is >gasoline. Would you please explain why this fact, which absolutely no one has disputed, is relevant to this discussion? Either cite a production car which is more efficient than an Insight or concede that hybrid systems significantly improve fuel efficiency. |
#126
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"Gordon McGrew" > wrote in message ... > Either cite a production car which is more efficient than an Insight > or concede that hybrid systems significantly improve fuel efficiency. How does it compare to the Smart fortwo? |
#127
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Dave > wrote:
> A hybrid also allows the designer to readily shut the engine off on > idle. In theory, you could do this with any engine and just use the > 12V+starter to get it going again. Practically, no one does this. > I suppose for drivability, NVH, and maybe starter motor wear issues. In Milan, Italy, all cars were required to auto-stop, with normal engines and starters. This led to substantial problems with worn out starters, premature battery failure, and led to dubious improvements in air quality. The hybrid spins the engine at 1000 RPM to start the engine, higher than the 150 RPM startup of a typical engine, yielding a cleaner startup. The effort for the hybrid to start the engine is obviously trivial, and often cannot be felt, whether auto-start or key initiated. > Last, a hybrid allows downsizing the engine without sacrificing > performance. A smaller engine runs at an average higher load, where > (see above) it is more efficient. My Honda hybrid with CVT is far more pleasant to drive than a Civic with an automatic. It is smoother and quicker in town. > Certainly there are minuses (cost, weight, complexity), and yes, the > real-world gains never seem to match the advertised EPA numbers. My Honda highway mileage exceeds EPA estimates. My city driving is a little lower. The Escape/Prius/Lexus hybrids don't perform up to EPA spec in the city, because no one drives a city cycle. The fact that the highway mileage is lower than the city mileage makes a "normal" blend of driving lower than the EPA city rating, where consumers have gotten used to the city EPA being something achievable as an average. If you try to drive one of these undersized engines for something resembling performance, the MPG plummets. It's a little tiny engine, and it can't work hard for long. The regen isn't going to help out long term without some gaps in the demand. When I tow a horse trailer with my Escape, I get about 17mpg. That is likely the same as a V-6, and I have less power for long grades, although acceleration is fine. I just can't maintain that power load for very long. -- --- Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8,-122.5 |
#128
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Gordon McGrew wrote:
> On Sat, 06 Aug 2005 04:27:14 GMT, "FanJet" > > wrote: > >> Bebop wrote: >>> FanJet > wrote: >>> >>>> Bebop wrote: >>>>> > wrote: >>>>> >>>>>> I would stay away from hybrids. Saw one die in the middle of >>>>>> traffic - no power and creating massive backups. The industry >>>>>> will eventually go to hydrogen systems, but never electric. >>>>> >>>>> The hybrid is not true electric, thus the word "hybrid". >>>> >>>> Actually, they're true gasoline since that's their *only* power >>>> source. "Hybrid" is a spin that gets people to purchase something >>>> they otherwise wouldn't. >>> >>> >>> Not excatly, you can run the car on battery alone. But you will not >>> get far on it. Some people have managed to alter the program on the >>> car's CPU and allows it to run longer on battery and recharge it at >>> night to get better mileage. >> >> How do they recharge it at night? > > They have retrofitted a line voltage charging system, an option > available only if you have a hybrid system to start with. > Manufacturers are considering adding this as standard equipment to > their hybrid vehicles. Which does nothing but move the pollution upstream and make it virtually impossible to accurately calculate MPG. >> >>> A true gasoline car of the same displacment will not get that kind >>> of mileage, but a hybrid will. >> >> The Prius and the Honda hybrid have only one external energy source >> which is gasoline. > > Would you please explain why this fact, which absolutely no one has > disputed, is relevant to this discussion? Sure. Inserting a series of extra energy conversions isn't a typical path to improved efficiency. Increased efficiency leads to greater MPG. > Either cite a production car which is more efficient than an Insight > or concede that hybrid systems significantly improve fuel efficiency. I'll do nothing of the sort. My point is that car manufacturers have sidelined innovative gasoline powered automobile improvements by creating and selling a niche car that in practical terms isn't a big improve at all. Further, exemplified by the new Honda Accord hybrid, they veil the truth in a bunch of marketing crapola. |
#129
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Steve Bigelow > wrote:
> How does it compare to the Smart fortwo? Some Canadians are citing 65mpg on the highway in the smartfortwo, which would seem to be 54MPG US. Canadians are reporting 88MPG highway with the Insight (73 US MPG). What would a smart car get with a hybrid option? An Insight without the hybrid? -- --- Clarence A Dold - Hidden Valley (Lake County) CA USA 38.8,-122.5 |
#130
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Gordon McGrew wrote:
> On Sat, 06 Aug 2005 04:21:09 GMT, "FanJet" > > wrote: > >> Gordon McGrew wrote: >>> On Wed, 03 Aug 2005 20:30:50 GMT, "FanJet" > >>> wrote: >>> >>>> Gordon McGrew wrote: > >>> Really? Don't all cars have advanced engines and computer control >>> these days? I am not aware of any particular advancements in the >>> Prius' gasoline motor which would explain it's exceptional fuel >>> economy. The computer only improves economy because it has a >>> battery and motor to control. If manufacturers could get the same >>> benefit without these expensive parts, why don't they do it? The >>> fact is that the most advanced gas engine with computer control >>> cannot match this efficiency level, at least not with acceptable >>> performance. >> >> No, the fact is, with the exception of a truly minor assist from >> regenerative braking, the hybrid's only source of energy is gasoline >> - just like a non-hybrid. > > What did I say that would lead anyone to believe otherwise? The issue > is how the hybrid system improves the efficiency of conversion of > gasoline to kinetic energy. Saying that the only source of energy is > gasoline is a red herring. 'Gasoline only energy source' needs repeating because inserting energy conversions into an existing system doesn't magically result in an efficiency improvement. In the case of the hybrid, the real improvement is small and it is largely due to increased efficiencies that could be economically added to non-hybrid vehicles - like low resistance tyres, for example. Of course, like other efficiency improving hybrid systems, not everyone likes the results. In this case, the handling ability of low resistance tyres sux. > Actually, the only source of energy is the Sun. Mother Nature just > converted a portion of the solar energy to oil for our convenience. Not exactly, but... >> The comparison becomes even more interesting when you >> consider that the regenerative braking assist is rendered less >> significant because the hybrid is required to carry the extra weight >> associated with the extra electrics/electronics. Then, there's the >> losses associated with mechanical > electrical > electrical > >> mechanical and all the way back for regenerative braking (maybe less >> the dc > ac conversion). Just doesn't add up. > > Of course, any conversion from one kind of energy to another involves > inefficiencies. Merely listing them out says nothing about the > overall efficiency of the system. When they are non-existent in the original system, listing them becomes very important. > Honda did use regenerative braking of a sort on a Civic model about 15 > years ago. The computer would only allow the alternator to supply > power when the vehicle was decelerating (or if the battery charge > dropped too low.) It's benefit was pretty small. So simple. They should've kept it. > Diesel locomotives drive generators which power electric motors which > move the train. Why not just have the diesel engine turn the wheels > directly? Because the use of electric conversion is more efficient > overall, even though the extra conversion involves a loss of energy. > The railroad companies don't buy diesel-electric locomotives so they > can brag about driving a hybrid. And all the energy comes form diesel > oil. Actually, diesel-electric locomotives are the way they are for reasons completely unrelated to efficiency. Understandable when you consider that the design dates from a time when fuel efficiency wasn't a design consideration. Reliability was the paramount consideration. >> And, there 's more to the story too. The performance boost you're >> referring to is only there for a brief period of time. Soon the >> batteries need a charge and the ICE isn't powerful enough to fully >> charge the batteries and simultaneously power the car so, it mostly >> powers the car. There is no free lunch. > > You seem to believe that everyone who buys a hybrid thinks he owns a > perpetual motion machine. The fact is that the performance boost is > only needed for a short time. Most car engines spend only 1% of their > working hours producing their rated horsepower. There is lots of > extra capacity for charging the batteries. This depends entirely on need. Some needs are serious and immediate. For example, if I've just exhausted the battery by getting to speed and jocking for position on an interstate, what happens if I need maneuvering power to avoid a potential accident situation? In this case, today's hybrid is actually a safety liability. I'd be interested in know the source for your use of 1%. You need to keep in mind that the 'lots of extra capacity for charging the batteries' consumes gasoline that would not be consumed in a non-hybrid vehicle. > Other posters have listed numerous reasons why hybrid systems increase > efficiency. It could be all academic except that hybrid cars are at > the top of the chart for high-milage gasoline road cars. Other than quoting MPG figures, not really. The only system that is a net + is regenerative braking and, truth be told, it's not that big a deal. The chart topping had much more to do with driving style & political posturing than science. > >>>> So, when you think >>>> current hybrid, you should think Fahrfurnugen, Cab-Forward design >>>> or hemi. You might also throw in extra profits & CAFE. >>> >>> I thought everyone was saying that the manufacturers are losing >>> money on hybrids. As for CAFE, it wouldn't help your CAFE if it >>> didn't improve milage. >> >> Not sure what everyone else is saying but I can tell you for sure >> that the car makers aren't philanthropic organizations. Nearly all >> of them improved CAFE figures by simply insisting that everyone use >> 5W20 weight motor oil. The manufacturers didn't charge a thing and, >> other than adjusting documentation, it didn't cost them a anything >> either. > > And it didn't provide much benefit either. Can you point to any cars > which increased their EPA milage ratings by even 1 mpg as a result of > switching to lighter oil? True but the change apparently netted the manufacturers what they needed and that's what they were after. |
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