evone, don't you think it's customary to introduce yourself and whatever you drive first? Why don't you have a meaningful profile? It goes a lot better than just jumping on a potentially controversial topics. Not saying what your intentions are, but an intro might help....

I'm very happy with my Honda Insight, but I'm not going to make strong judgements about hybrids from Toyota, Ford, or GM. I've driven an FEH briefly. Each system has it's pros and cons, but I'm not going to put one down in favor or the other. Besides, the technology is not mature.

61.5mpg lifetime - 82mpg in recent months

Best Run >
www.cleanmpg.com

"fanatic" is what the lazy call the dedicated

My bet for 2009 Prius is still gas-electric hybrid.
It'll be cheaper, better mileage and non-plug-in.

Ken@Japan

Evone I'll have to agree with Delta Flyer here regarding introductions. Some may read you as being a "my car is better than your car" kind of person which I don't think was your intent.

Personally I think both technologies are great.
I plan to drive my car over 350,000 miles so I chose the Civic, which can be driven on almost flat hybrid battery. If it goes bad at....say 200-250K miles I'll have a choice to replace the battery or drive it as is. There is no choice with the other technology.

I'm in favor of both systems as it gets people familiar with electricity used to drive the car and shows advancement from the wonderful EV1.

You have some very good points especially regarding EV mode and plug-in capabilities and know how much you love your car...but remember others have their own reasons too!

Efficient drivers do it better.
1003 miles a tank personal record. 74MPG calculated. HCH1 CVT

I am a strong proponent of consumer choice. I would love nothing better than to walk into a car dealership and be offered a choice of a parallel hybrid Sedan with 50 mpg, or a series hybrid with 80 mpg, or an all electric with a 250 mile range, or a series hybrid SUV with wheel motors that will blow anything on the market away and still get 60 mpg. But I can't get what I want, namely the series hybrid all electric, and I know dam well there is no technical, economic or marketing reason why I cannot get my preference. The old adage is " you can fool some of the people, all of the time, and all of the people some of the time, but you can't fool all of the people all of the time", and I'm no fool, and I bloody well know when someone is trying to pull the wool over my eyes. These corrupt, arsehole bastards are forcing global warming down peoples throats by not offering any significant choice, while fostering this disinformation campaign, that they really are pro-environment, because of all of the money they spend on the nutty freedom car / hydrogen economy / fuel cell car fantasy. Check out:
http://socialwork.arts.unsw.edu.au/t....Hydrogen.html
for the truth about that.

So go to your car dealership and be offered the choice of the fuel guzzling SUV clone, or the fuel guzzling Sedan clone, or the fuel guzzling truck clone.

Personally I'm not an environmentalist but I'm with you on your other points.

I'd LOVE to be driving a cool electric car, and there is no reason what-so-ever they are not available today other than the politics of oil and selfish car companies.

Efficient drivers do it better.
1003 miles a tank personal record. 74MPG calculated. HCH1 CVT

Hi Ken, what are the Japanese motoring press saying about this? Still all speculation? How about a factory plug-in "option"?

Cheers,

Clett

http://mysite.wanadoo-members.co.uk/ecotech/ecot.htm

Hi folks,

When looking at the efficiency of any system, the general rule of thumb is the product of all efficiencies is the total, tank-to-wheel efficiency. For example:

MECHANICAL
(35% ICE) * (95% 1st gear) * (95% 2nd gear) * (95% 3d gear) =
(35% ICE) * (86% three gears) ~= 30%

SERIES ELECTRICAL
(35% ICE) * (90% generator) * (90% converter) * (90% motor) =
(35% ICE) * (73% transfer) ~= 25%

However, this simple model ignore the operating range. The flaw is high ICE efficiency is available only in a narrow speed range. Partial power modes become much less efficient and this is where the mechanical transmission system falls down. Typically, the mechanical ICE is running at substantially lower efficiencies, 25%. In contrast, the series system can keep the ICE in the peak efficiency modes:

MECHANICAL
(25% ICE) * (95% 1st gear) * (95% 2nd gear) * (95% 3d gear) =
(25% ICE) * (86% three gears) ~= 21%

SERIES ELECTRICAL
(35% ICE) * (90% generator) * (90% converter) * (90% motor) =
(35% ICE) * (73% transfer) ~= 25%

This is one of the reasons we find some hybrid skeptics 'game' informal MPG testing in their articles by using narrow test environments. They also use a manual transmission to avoid torque converter losses. So how does a parallel hybrid electric come out?

In a well designed system, it uses the MECHANICAL efficiencys when they are best and ELECTRICAL efficiencies when they are best. We can actually see this in my MPG distribution data:



That tail on the right edge reflects success in being in the 'sweet spot' of either the electrical or mechanical system efficiencies. It takes planning and attention to detail but it shows the potential of my Classic, 03 Prius. The current Prius has tuned the system to move the peak further to the right, apparently an extra 3 miles per hour.

IMHO, it makes sense to provide a mechanical path for high-speed ranges because that is where the ICE and transmission efficiencies excel. At lower speeds and under variable speed ranges, the electrical transmission system works best. Although it is harder to design, with good computer control, the vehicle can achieve optimum performance.

IMHO, a parallel system can achieve the best total system performance over those having only a mechanical or electrical transmission system. But it takes attention to detail to make sure the vehicle works in the "best" of each mode across all operating conditions. It means the designers have to abandon the bias of "all problems look like a nail when you have just a hammer."

Bob Wilson

ps. Thanks for moving the thread!

Operation Iraqi Oil Freedom:

Automatic, stock, project car.

My other 1500 cc car:

Automatic, stock, backup car.
Free speech, dialog and knowledge thrives without the poison of SPAM.

I've never trusted press messages.
http://www.toyota.co.jp/en/vision/message/conference/
Toyota president Watanabe stated they are developing plug-in hybrid but there was no Prius name.

Ken@Japan

This is an excellent point. One potential point that could be in favor of series hybrid however is that if the engineers know in advance the engine only needs to run at a fixed-speed, it would be possible to design it with a greater max. thermal efficiency than a normal 4-stroke engine, which is great for torque and throttle response. Use of an exotic engine cycle, a recuperated turbine engine, or even some sort of external combustion engine might be a more efficient primary powerplant.

However, one advantage that the parallel hybrid system has over the series-hybrid is the ability to combine engine power and electric power if needed. Considering that many electric motors have excellent power density however should mean it's possible to throw a large motor on the rear axle, and one each on the front wheels to produce more than enough horsepower in a series setup.

Another idea I've thought of however for a series-hybrid is that a fixed-output engine could still be used, but with a single mechanical gear on a clutch that would allow it to act as a parallel hybrid at high speeds. If say 20 horsepower were needed at the wheels to cruise, and the engine were putting out 30 horsepower, Instead of converting all of that to electricity and back, it could be clutched to the wheels, and a 10 horsepower charging load added to it, sending 20hp directly to the wheels, and the rest to the batteries.

Finally, an advantage of series over simple elecrtic is that for short trips, the series model can act as a pure electric. However, the engine can come on for longer trips (sparing the batteries from being deep cycled, which should extend their lifetime) and if cabin heating is needed (electric heating costs money and reduces range, unlike using wasted engine heat).

Bwilson4web and Double-Trinity you are both totally right.

The millstone around the neck of ICE development is the need to connect it to the wheels via a gearbox. This means the ICE has severe design constraints, such that it must have good torque at most rpms, idle well, start quickly, be smooth at all rpms and most restrictive of all have good throttle response.

An ICE connected to a generator has none of these concerns, so you can design it purely for outright thermal efficiency. A 50% engine would be no problem, such engines already exist for electricity production in ships. All you need to do is get rid of the gearbox and free up the remaining potential of the internal combusion engine.

It's interesting to note that the engineers behind the Prius installed the hybrid system NOT mainly to collect regenerative energy (which contributes only a little in Prius), but so they could run the more efficient Atkinson (well, Miller-esque) engine cycle they wanted. It had too little low rpm torque so wouldn't have worked without the help of the electric motor. The next logical step is to move up to series-hybrid.

http://mysite.wanadoo-members.co.uk/ecotech/ecot.htm