Re: Ford Hybrids and cold weather
 

Please re-read the last line in my post.....

You know what they say about opinions.....

I do understand kinetic and dynamic energy levels, propulsion systems, energy use under load and energy recovery. A car that is at a high altitude has stored kinetic energy that has ALREADY been expended to get there. It makes no difference if you use a hybrid electric motor/gas engine, diesel engine, gas engine or a team of wild donkeys to get it there. All a hybrid will do is recover that kinetic energy into a usable form instead of dissipating it as heat lost during braking. I'm not sure about your Ford but the Toyota's I'm familiar with will recharge the traction battery while the engine is warming up and the car is moving forward.

A non hybrid running an Atkinson cycle engine is NOT comparable to a hybrid as the engine will be underpowered during maximum acceleration unless it is either supercharged or has forced induction by a turbo. Either of those solutions will increase fuel consumption.

As far as the electric motors making the car more efficient at interstate speeds, going uphill, the electric motors will supplement the gas engine and cause LESS fuel to be burned and that extra kinetic energy is then recovered on the downhill side resulting in a net gain over a non hybrid car.

The hybrids we drive are not "party tricks", just well engineered vehicles that extend the distance traveled by using basic engineering principles to maximize energy use.

Re: Ford Hybrids and cold weather
 

Georgia- Love your statement: "Modern hybrids are not simple, not easy to decipher and will be a constant source of arguments until long after we are gone....." I agree. They are NOT simple machines at all. The idea is old. It took modern computer power under the hood to make it all work reliably.

Gpsman1: 3525+ posts and has been explaining, experimenting, and deciphering the FEH since 2005.

xspirit: 47 posts and has obviously not read many posts because he already thinks he knows it all. (maybe should take a bite of humble pie?)

About the only fair truth (from xspirit's unique ability to state the obvious) is every mile traveled in a FEH comes from gasoline or a gasoline/alcohol mixture.
No sh1t Sherlock.

While I only stated generally speaking before, now I will get specific. I know you want specifics.

A same size & weight Escape gets an average of 24 MPG on a CITY test course. The Hybrid Escape gets 36 MPG on the same course.

That's 12mpg more. Why?

It is NOT from regenerative brakes alone.
And let's clear up that tapping the brake pedal, coasting in D, and coasting in L, with or without the gas engine turning is the exact same form of regenerative braking. And to be crystal clear, you don't get ANY "regeneration" from the gas engine, only generation.

From materials published by FORD at the time of vehicle launch in 2004-2005:

41% of that 12 MPG gain is from regenerative braking. Not all. Not most. Some. 41% to be EXACT.

23% of that 12 MPG gain is from the Atkinsen engine.

16% of the 12 MPG gain is from engine off time at stops.

8% of the 12 MPG is from the eCVT.

5% of the 12 MPG is from specially designed LRR tires.
( while possible to put on any car, they are not due to added cost.)

The balance 7% comes from a total of many small factors, including the electric motors ability to act as a load leveler, allowing the gas engine to stay in the most advantagous "sweet spot" more of the time, and so on.

Please note that while the above figures are for the published, official, city test drive cycle, the following is true on the highway:
You hardly ever tap the brakes, so regeneration is reduced to times of coasting or significant downgdade.
You STILL HAVE the benefits of the Atkinsen engine.
You STILL HAVE the benefits of the eCVT.
You STILL HAVE the benefits of the special LRR tires.
You STILL HAVE the benefits of the motors load leveling and engine governing.

This hybrid SYSTEM is giving us all lots of gasoline savings without a single watt-hour of regeneration.

In fact, while not technically feasible in the Ford Hybrids for a number of reasons, one being there is no 12 volt starter, it IS POSSIBLE to drive a HONDA hybrid without a functioning HV battery. I have a 2000 Honda Insight with the orginal battery pack. At 14 years old my pack is all but dead..... (for you Honda owners, I'm at about 150,000 miles, Have had the IMA light and "battery end of useful life" code for over 3 years now, and I still drive it almost every day, and have about 30,000 miles since my IMA light came on.) I still get 63 - 65 miles per gallon in that hybrid car without a fuctional hybrid battery. All possible because Honda included a 12v starter. The MPG did not change much at all without having the ability for regen, but PERFORMACE is reduced. Much less pep... slower acceleration without battery boost.

The fact is, a gasoline otto cycle (typical) is only 20% efficient. 80% of all gasoline btu's, calories, whatever energy unit you like, goes into heat that is dissapated into the environment. 20% is pushing you down the road. But when you are STANDING STILL 100% of the gasoline is going into waste heat (or a trivial amount charging your 12v underhood battery.) Burning gas is converting chemical energy into heat energy at 80% and into mechanical energy at 20%. (diesels a little better)

For comparison, an electical motor converts chemical energy (battery ions) to mechanical energy at greater than 90% and less than 10% goes into waste heat. And when you are standing still there is zero wasted energy!

Having the gas engine off for as many MINUTES as possible should be everyone's goal, not miles "propelled" by battery power in EV mode.
This can only be done at the lower speeds in Fords, but at higher speed in some cars.
It is HUGELY advantagous to run the car from the battery as much as possible.
I choose my words deliberatly. I mean RUN all the sub systems of the car, power steering, power brakes, water pump, even the climate control from the HV battery pack only, gas engine off, in EV mode whenever possible..... you are saving gas every minute you do so without breaking any laws of physics by not dumping all that waste heat to the environment.

For what it is worth, I can repeatedly and consistently achive 53 to 54 MPG city in the FEH by "tricking" the stock system into EV mode as much as possible, and using many small energy saving techniques bundled together. It is not magic... Anyone can do it, and I know many who have. On a one hour, 24 mile drive I have the engine on for 14 minutes and off for 46 minutes. A complete round trip to the same parking stall, no elevation change, in real city driving, in the middle of the day. Ideal weather. So it is a fair, realistic trip. How's that for a nice party trick and 700 miles per stock fuel tank sometimes.

Hope you found that helpful.

Re: Ford Hybrids and cold weather
 

A) No. A non hybrid could not (usefully) use the Atkinson cycle engine the FEH. There is not enough torque from the engine to launch the vehicle from a dead stop. Hence the integrated 94 HP electric traction motor that gets your Hybrid Escape rolling from zero to about 10 mph each and every time. Engine on or not.

B) Oh how much you have to learn. :angel: While any car can have a form of CVT which means "continuously variable transmission", only a parallel hybrid, (Ford, Toyota) can have an eCVT. See that little "e" there? That makes this case special. That "e" means electric(motor) continuously variable transmission. Only hybrid cars with electric motors can have one of these puppies, which are different animals.

Now I may confuse you, but every FEH has a fixed gear ratio between the engine and the generator and the traction motor and the wheels. Sounds contradictory to the above, but its not.
If you can explain what I mean by that, you'll get much street cred.

C) I'll let you talk to the Chevy Volt people about your fear of "burning gas to generate electricity to power a motor to turn the wheels" not being efficient- Since it does that full time.

D) Any time you drive your FEH in reverse it drives EXACTLY the way a locomotive does. What? disagree? Try draining your HV battery to the minimum so its removed from the picture. Hint: Betcha still can drive in reverse! ;)

Re: Ford Hybrids and cold weather
 

Your description of "stored kinetic energy" is more properly called "potential energy". Other than that, your description of it is the same as mine rather than being a contradiction.

Yes, the Escape recharges the traction battery while warming up as long as the battery is not mopre than "half" capacity. When it is moving forward and there is no demand for electric assist, and the battery is below half charge, the gas engine will be used to raise the charge to half charge. There is no way this charging does not require burning additional gas, if that's what you are implying. The gas needed is not fairly characterized as "minimal" or otherwise. It's whatever it takes. If the boost provided by the system is significant, then so is the gas needed to create that boost.

No, you can also increase trip time by having a lower average speed. And you and gpsman1 should agree on whether a non-hybrid can use the Atkinson cycle.

Here is what you said the first time: "The electric motors will supplement the gas engine as required to increase the operating efficiency while moving. I think your meaning would be more clear if you referred to the electric boost being the prime contributor to this efficiency. Without it, the electric motors can't contribute anything.

You've twisted my words. I didn't say hybrid cars are "party tricks". I said the ev mode has similarities to a "party trick". The ev mode in the Prius, Escape Hybrid etc. is of relatively trivial utility compared to what a Tesla does. Not that it isn't beneficial, and not that it can't impress people when you demonstrate it, but we all know how limited it is. You would be aware that newer hybrids have more capable ev modes.

Re: Ford Hybrids and cold weather
 

And what I said sounds remarkably similar: "While the minute detail of how systems such as the FEH's hybrid system works certainly is complex, the basic principles are quite simple and have been understood for a long time. I am quite aware of the complexity of computerized control systems and modern electronics.

Surely you are aware there are very prolific posters on some forums who post garbage, and the inverse is true also.

No more insults or personal attacks please. It is not becoming and does not enhance your obvious depth of knowledge of these subjects.

It's true that rather than use L to slow down, I could be using the brakes and the same thing would be happening. I never suggested otherwise. I suppose using the brake pedal would waste a bit of energy to light the brake lights while using L when coming to a stop delays engine shut-down.

Whether you want to call it regeneration or generation seems like a moot point. We both know we're talking about the same thing.

The 47% number for regenerative braking will depend on specific parameters of the test. You could do a test with only one instance of braking, for instance. Therefore your use of the word "EXACT" to describe the percentage is improper, and therefore also all the percentages depend on the particular test regime.

So the gain from regenerative braking is the largest source of the hybrid's efficiency in city driving, and the only one of these features that a non-hybrid could not have (assuming a general equality of a hybrid having an eCVT and a non-hybrid having a CVT).

You don't live where I do, where highway driving involves sharp corners and huge elevation gains. A return trip betweeen Vancouver and Whistler includes hundreds of corners and a net elevation gain of 11,000 feet.

Our problem is that you're including more things as part of the hybrid system than I do. I include only those things covered by Ford's 8-year warranty on the hybrid system. Anything that a non-hybrid could have, such as LRR tires, should not be considered part of the hybrid package for the purpose of this discussion.

In response to people worried about hybrid batteries having to be replaced, part of my comments have been that they are outlasting the cars. (Maybe not for your Insight, but almost no batteries are being replaced in Prius' and Escape Hybrids. You would know how much mileage is being put on these cars used as taxis.) My other response has been that the hybrid cars don't suffer greatly by degraded capacity of the hybrid battery.

In fact, elsewhere in this forum I recently posted:

"Even if the traction battery loses capacity, it helps to estimate the effect. Even with no traction battery capacity, you still have the benefits of the CVT, smaller than normal gas engine, LRR tires, airflow tweaks, engine shut-down and Atkinson cycle gas engine. So the hybrid electric system is only part of the gas-saving aspects of the vehicle. I have no idea what proportion of the gas savings is due to the regeneration system, but an estimate might be 65%. So if your battery loses 15% capacity, that should mean a loss of 15% of 65%, which would be a 10% difference in the mileage benefits provided by all the car's features. Note that this is not a 10% mileage loss, just 10% of whatever the FEH achieves over a non-hybrid. Which would amount to very little."

So you can see that we're on the same page on this stuff. You can also see that my uninformed estimate for the contribution of the regeneration system, 65%, was high compared to the 47% you've quoted, but in the same ballpark, not bad for a guess, and would depend on the driving cirucumstances.

Not all of the gas engine's energy is wasted when idling at a standstill. When idling at a standstill the gas engine is also warming itself, the cabin, catalytic converter and traction battery as needed. And recharging the traction battery if it's below a certain charge level.

Other than that, I agree with you, and agree that the distinction between having the gas engine off and being propelled by battery power in ev mode are two different things. You can coast or sit at a stop with the engine off but not be using ev propulsion.

Thank you for clarifying the intent of your previous statement: "it's not the number of miles in EV mode, it's the number of MINUTES a year you are in EV modd that really saves a lot of gas."

How you drive may be utterly impractical for many or most hybrid owners. Where I live, using ev mode more than minimally is going to severely piss off a lot of other drivers, and flat roads are rare. If we want more people to buy into this technology, there's no sense making hybrids and their owners look like turkeys by impeding traffic.

We agree it's good to keep the gas engine operation time to a minimum. Where we disagree boils down to determining if beyond a certain point, those gains are offset by conversion losses caused by overly forcing ev mode. You may be correct, but it may be a matter of the test conditions. I kow that conversion losses are not fiction, and that the owner manual for my FEH warns that excessive forcing of ev mode can reduce mileage.

Why don't you do an experiment: do all the same things except tricking the car into ev mode for the same drive, and see what effect this has on mileage.

Are you saying that if an FEH had a "dead" traction battery it could not move from a standstill? Your claim that the Atkinson cycle engine cannot be used without a hybrid system is utterly wrong. The Atkinson cycle causes the engine to produce less power but runs more efficiently. It has nothing to do with starting torque except that it may be reduced. Atkinson cycle engines are more suitable in hybrids than non-hybrids because of the efficiency gain can be utilized while the electric motor can provide the missing power when needed. But there's nothing to prevent using an Atkinson cycle engine in any car.

"eCVT" is more a marketing term than the proper name for a planetary gearset or power sharing transmission.

But let's say the comparable car uses a CVT instead of an eCVT. That does not alter the substance of my point. It may not make sense to use an eCVT or electronically controlled planetary gearset in a non-hybrid, but I don't know that it's impossible. Some multiple-speed bicycles use planetary gearsets, after all.

I'll admit to not fully understanding how the power sharing transmission, or planetary gearset, works in the Prius and Escape Hybrid.

Your quote attributed to me contains a significant error. I said: "to burn gas to power the engine to turn a generator to charge a battery and then use the battery to turn an electric motor to turn the wheels."

Your incorrect version says: "burning gas to generate electricity to power a motor to turn the wheels"

See the difference? The scenario I listed includes more conversion steps and so would suffer more conversion losses. The FEH's ev mode works as I described, not as you mistakenly attributed to me.

But since you raise the Volt, let's take a look at it.

First, it uses premium gas while the FEH uses regular.

Consider this from Wikipedia about the Volt: "Under the gasoline-only scenario (never charge), the 37 mpg-US (6.4 L/100 km; 44 mpg-imp) figure results from 35 mpg-US (6.7 L/100 km; 42 mpg-imp) city driving and 40 mpg-US (5.9 L/100 km; 48 mpg-imp) on the highway."

I'm not the first to point out that the Volt does not have very impressive gas-only mileage, and some have speculated that it is because of conversion losses. These are not stellar numbers for a car that has various other mileage tweaks, so the numbers do not back up your position that the Volt's system is efficient in gas-only operation and do not support a claim that gas->generation->battery->propulsion is more efficient than gas->propulsion. Once again, there have to be conversion losses.

You're correct that the FEH does work like a locomotive in reverse. The snark is not needed. I'd venture that the FEH works the same way for a while immediately after a cold start. I certainly don't drive in reverse enough to affect my mileage. Does this mean you are agreeing that the FEH does not work like a locomotive the vast majority of the time?

Re: Ford Hybrids and cold weather
 

OK, I don't have time to write novels and tried to keep my explanation simple to allow more readers to follow but it's apparent you are arguing just to see your words in print. No matter how high you pile it, it's the same material...

I'm done and moving on as it's obvious that you don't want to learn, don't understand how they work, just want to be argumentative and I'm tired of your BS. At he very least, try to read up and understand how MG1 and MG2 make up the star and ring gear on your hybrid and the motor is on a planetary gear set between the two.

Re: Ford Hybrids and cold weather