My fuel economy master equation

[alpha754293]

The Ford Fusion Hybrid 2013 SE is my second Hybrid that I own after trading in the Civic Honda Hybrid 2007 and at that time I believe there were only 2 hybrids on the road (Prius & Honda). Correct me if I am wrong.

When I owned the car I was extremely conservative in driving and I would commute about 60 miles round trip on very flat land and was able to obtain 50-60mpg. Of course windows open and driving 55mph. Honda's claim that year was 49/51 mpg. Many people complained that they were not achieving those numbers and they were later sued and were supposed to produce a video which you could watch on line to achieve those numbers or close to them.

The Honda at that time was using Nickel Hydride batteries and the engine was linked to the Hybrid battery and not like the Ford Fusion Hybrid today where you can use EV without causing the ICE to start up. Honda did claim under certain circumstances you could separate the engine from the Hybrid Battery, but I never observed that.

So I became interested in Hypermiling at the same time and started applying some techniques that I had read about and still use them today with the Fusion. In fact hypermiling can also be used with non hybrids also.

If possible use brake lightly when coming to a red light, going down hill put car in neutral and from my observations the mpg increased rapidly as well as inflate the tires to about 45psi. My first set of tires were replaced at 48,000 miles and I considered that normal. Never had the nerve for getting behind a 18 wheeler and letting him pull me. No cruise when going up hill.

I'm not telling you new revelations and of course we know in the winter the mpg will decrease due to a richer fuel mixture and this I have noticed with the fusion also.

A definition of a hill to me is and this is for the ones that have travelled between Jellico TN and Knoxville TN on I-75 you know what I am talking about or the Hill once you leave the visitor's center from the TN side of the Smokie's and head towards Cherokee NC or vice versa, those are hills.

My Hybrid battery failed me in February 2013 however Honda's warranty was 8 years/80,000 miles and since I had about 72,000 they replaced the battery with a refurbished battery(Frame was old, but the cells were new) and No charge.

My daughter has a 2009 Civic Hybrid and I believe with a Nickel Hydride battery and hers went bad also and no charge to her. Then I decided to trade.

The spec's with Ford Fusion Hybrid SE and comparing to a Prius V are like night and day to me and the Fusion was my only choice.

BTW my brakes on the Honda at 72,000 were 40% in the front and 50% in the rear.

 

 

This is from a Civic Honda Hybrid owner 2007

 

have noticed other people complaining about the mileage being poor, which I would attribute more to driving habits than capability of the vehicle. Where I live in Maryland is very hilly and I still manage over 49 mpg, sometimes over 50. It can be done, one just needs to understand that quick acceleration, trying to maintain 65-70 uphill, idling, warming up the car, etc, will cause mpg to go down (especially idling/warming up the car as you are registering 0 mpg the entire time). The car handles excellent around corners and in all kinds of weather and is easy on the tires (my original set lasted over 74,000 miles). While it doesn't specifically say it in the manual, I have found better performance is achieved when using premium gas. That really isn't a big issue because you're typically looking at a difference of $1-$2 on a fill up when compared to regular since the gas tank isn't big (I typically fill up around 9.2-9.5 gallons).

 

I am not here to criticize anybody's driving habits, but just to let you know the complaints are with other auto manufacturer's as well.

So can anybody explain how some do well and others don't?

 

2007 - uhhh....I think that there might have been also a Malibu eAssist "hybrid" (mild hybrid) as well.

 

Full hybrid - 2007 - probably.

 

So, a couple of things - if I remember correctly, the Honda hybrid system - the transmission coolant pump ran off the engine (I think that it had to stay in drive for it to be powered via the torque converter/torque converter clutch) so if you are doing highway speeds and then popping it into neutral, you're actually shutting off the transmission coolant pump. Which probably wasn't the best thing to do to your transmission. (It was like that at least with the Honda Insight).

 

From what I've seen in the FFH, if you pop it into neutral (I have not found a transmission coolant pump, but I'm still digging), you actually detach the entire regen/EV motor/planetary CVT from the engine which means that you get zero regen off of it. (Please check and verify that, cuz I've only done that at relatively low speeds). But I do believe that the transmission cooler is now electric, so it isn't tied to the gear selector.

 

Be careful that you don't blow out your tire by overinflating it. If you do that, and you crash, you've exceeded the manufacturer's recommended tire pressure, at which point the onus is on you. And if you have a relatively low profile tire like I do on my Titanium (235R45/18), you're putting a LOT of pressure/force on the walls of those tires. So be careful with that.

 

The problem that I have with people who don't use cruise up on the hill (or down it for that matter) is that there's a HUGE variation in speed. It can EASILY be +/- 20 km/h. If you don't obstruct the flow of traffic, that's fine, but a lot of people DO and so for people like me who DO use cruise, I end up having to slow down because of those people. Granted, there are probably times and places where going up and down hill, I would shut off the cruise because the control response cannot get ahead of the "curve" and you end up with a bit of a phase offset between the terrain plot and the speed plot, so then I switch over to manual control so that they're matched better, but wildly varying speed is dangerous.

 

I think that the driving environment has a pretty big influence on how people drive as well. For example, where I work in Southeast Michigan, the on-ramp from Eastbound 8 Mile Rd. (MI-102) (yes THAT 8 Mile) to Northbound Telegraph Rd. (US-24) is a 25 mph super tight loop, but then the flow of traffic on NB US-24 is 55 mph (at least) and you only have a few hundred feet to get up to speed.

 

The onramp to NB I-75 from SB/EB Southfield Freeway is another 25 mph tight loop, and then I-75's flow of traffic is 75 mph, and it's going UP hill in addition to all of that.

 

Also, in SE Michigan, it's still VERY much classic muscle car country. You could be doing 80 and STILL be passed like you're standing still with portions of it being very flat, so you don't ever lift off the throttle (like you can by TN/KY or MD/VA/DC area). So when people start complaining about why they're not getting the advertised fuel economy numbers, those are some of the kinds of questions that I've started asking because it has a tremendous impact and influence on the kind of fuel economy you CAN or should be able to realistically expect to get.

 

The other thing that I think people don't realize is that the EPA test is a lab test. It's not the so-called "real-world" test and while I can't officially comment on the specifics of it, but you can bet that there's been meetings with the EPA and Consumer Reports specifically about this "type" of issue, which as more and more electrification across the ENTIRE field of vehicles from ALL OEMs, this will rear its ugly head time and time again unless a proposal to change how this is handled is published in the Federal Register.

Edited August 14, 2013 by alpha754293

[alpha754293]

Here are some other thoughts that I was thinking about on my drive to work this morning -

 

Consumer Reports sells more magazines with a big flashy headline like "THEY LIED!" [cue dramatic violin music] as opposed to apply the rigorous scientific method, so that their claims are evidence-based, especially when it came on the heels of the whole Hyundai/Kia situation. And I won't speculate on the kind of staff that Consumer Reports do or don't have, but if I was an engineer there, I would want to make sure that what I am saying is scientifically sound and tested before going to print.

 

(http://news.consumerreports.org/cars/2012/12/video-tests-show-2013-ford-fusion-c-max-hybrids-dont-live-up-to-47-mpg-claims.html)

 

But in an article in Car and Driver, it actually goes through and does a pretty decent job at explaining why there's a discrepancy, something that CR doesn't do at all, or nearly as much, or as in depth.

 

http://www.caranddriver.com/features/why-is-the-epa-so-bad-at-estimating-hybrid-fuel-economy-feature

 

And notice also that the news outlets didn't really pick up so much on CR's article about the improvements in the latest campaign. http://www.consumerreports.org/cro/news/2013/07/ford-to-improve-fuel-economy-of-existing-hybrids/index.htm

 

Also note that they didn't say that they were "wrong" in how they applied their test or perhaps the way they reported on it, but they weren't exactly being entirely forthcoming to say how it's not ENTIRELY correct either, which is also why you haven't read anything like the Hyundai/Kia thing from Ford, having to settle the "false" claims like our competitiors did/have to.

Edited August 14, 2013 by alpha754293

[alpha754293]

The other big reason why I chose the Fusion over the Prius (apart from the fact that the rear hatch breakover goes right across my rearview mirror with the way that I sit in the driver's seat), and I've already been rear-ended once in Michigan, so I would like to know what's coming up behind me at all times -- the Fusion got an "acceptable" rating on the IIHS small overlap rigid barrier crash test.

 

http://www.iihs.org/ratings/rating.aspx?id=1740&seriesid=561

 

By comparison, the Prius effectively "failed" the test by getting a "poor" rating in the exact same test. You can read the reports and watch the crash test videos. It's quite telling.

 

http://www.iihs.org/ratings/rating.aspx?id=1752&seriesid=740

 

And I do plan on having kids someday, so having a safe car is one of the critical factors that led to my buying a Fusion (among other critical factors).

[IraF]

Nice reply

Edited August 14, 2013 by IraF

[IraF]

Didn't know there were more then 2 hybrids in the year 2007

Edited August 15, 2013 by IraF

[alpha754293]

Nice reply

 

Thank you.

 

Didn't know there were more then 2 hybrids in the year 2007

 

Actually, in 2007, there were 19 hybrids in total (according to fueleconomy.gov) that year.

[IraF]

One learns something new every day. I guess Honda and Toyota were doing heavy advertising that year. The Missus bought a Yaris 4 door that year and I had a chance to sit and drive the Prius while she was looking at the Yaris and I wasn't too impressed with the 2007 Prius. A month later I bought the 2007 Civic Hybrid.

[alpha754293]

One learns something new every day. I guess Honda and Toyota were doing heavy advertising that year. The Missus bought a Yaris 4 door that year and I had a chance to sit and drive the Prius while she was looking at the Yaris and I wasn't too impressed with the 2007 Prius. A month later I bought the 2007 Civic Hybrid.

 

Learning is a good thing. I have a personal goal of learning a new thing everyday. (It typically actually works out to be a LOT more than that), but it's really the thought being the idea that counts (so as to NEVER stop learning).

 

One of the guys at work was telling me that the Ford hybrid development guys were benchmarking the Toyota system (which is pretty smooth already) and they were saying that it sucks and it wasn't smooth enough.

 

And driving the FFH, other than the engine noise, if you weren't paying attention or you have the radio/music going louder or louder road noise, it'd be MUCH harder to tell whether you're on ICE or in EV mode. It's eerie how seamless the transition back and forth is. Love it though. That's the way it SHOULD be.

[acdii]

My foot can tell, even if my body and hearing cant. Noticeable vibration when ICE runs. My mom said she got a nice foot massage on our trip to MN.

 

 

Hmm maybe thats why the car is so relaxing, you get a gentle massage and dont even know it.

[alpha754293]

My foot can tell, even if my body and hearing cant. Noticeable vibration when ICE runs. My mom said she got a nice foot massage on our trip to MN.

 

 

Hmm maybe thats why the car is so relaxing, you get a gentle massage and dont even know it.

 

Well, I know that *I* can tell partly cuz I'm kinda "trained" for it. That and also I drive two-footed, all the time. (I left foot brake and have done so for over a decade of driving). People are sometimes/usually surprised by that when I tell them that. I don't really see or understand why. Some people also make the mistake of then automatically assuming that I ride the brakes, which isn't true most of the time. (On non-hybrids, it depends. I might do that slightly more if I am stuck in a traffic jam to help curb the jerk).

 

But the nice advantage to doing it all the time is that when ever I jump in a go-kart, my brain is already pre-programmed that way, so I've been taken to tracks that I've never been to and be able to come with a second or two of the lap record and people are just completely baffled as to how I was able to pull it off on a track I've never seen/been to/driven on.

 

And it also works in normal full sized cars (like my FFH) when I took it up to the Waterford Hills race track, and coming to the end of the back straight where I'm already topping 90 mph, my "instructor" was progressively squeezing his butt hole (you can see him like tensing up in the passenger seat next to me) as I was passing the 200-feet marker in the braking zone, then on the approach to 100, you can VISIBLY see him tensing up even more, and I'm thinking to myself "okay, I better brake now before he shits himself in my car" [lift off right foot, slam on the brakes left foot, turn in]. And I only hit like 90% braking power. I NEVER actually managed to fully and completely slam on the brakes. Suffice it to say, the brakes in the FFH are VERY powerful. It had NO problems taking my 3772-pound car from 90 mph down to 40-something mph for the turn in for the tight right-hander. I only read after the fact that apparently the 70-0 distance is 177 feet which means that from 90 mph, even if I hit the brakes AT the 100 feet marker, I still would be slow enough to do the turn in for the tight right hander. That's pretty amazing if you think about it. And that's NOT an easy task for the brakes to do, but it does it so well.

 

But anyways, my point is - I could feel it a fair bit on my left foot. Course, for long distance drives, or whenever I'm on the cruise, my feet are completely off the pedals anwyays (unless they need to be on it to prepare for something ahead), but other than that, it's foot off.

[majorleeslow]

I just wanted to share some of my observations on how different loads affect my fuel milage on City and hwy. I did not record the SOC before each tip. But the data is pretty insightful (in my opinion). the number in brackets is ppl travelling total. no number = just driver.

 

F= Fan, R = Radio, D = Defrost etc see the key on some of the entries.

 

Questions welcome.

 

 

 

This one shows how trip distance affects the mpg.

 

Edited September 14, 2013 by majorleeslow

[majorleeslow]

These are all summer numbers no winter driving yet.

[alpha754293]

I just wanted to share some of my observations on how different loads affect my fuel milage on City and hwy. I did not record the SOC before each tip. But the data is pretty insightful (in my opinion). the number in brackets is ppl travelling total. no number = just driver.

 

F= Fan, R = Radio, D = Defrost etc see the key on some of the entries.

 

Questions welcome.

 

 

 

This one shows how trip distance affects the mpg.

 

 

Are the number of trips the number of times you've done that particular trip in order to give you the total?

 

I haven't tried to do any of this sort of statistics/data collection yet only because the scientist in me wants to make sure that all of the experimental conditions are identical, while the engineer in me says that it has to be relevant to how I am actually driving it, the moment that I am driving it (and since testing it under all of my possible driving conditions would be prohibitively expensive, yeahh....)

 

It's why I keep using the same stretch of highway not too far from where I live and why the test schedule is somewhat sparse (because waiting for the proper conditions so that when I am comparing one pair of runs vs. another; I would be able to make the apples-to-apples comparison - a fair bit harder in the "real world" on "real" public roads (i.e. not in a lab or at a development test track).

 

Also keep in mind that it looks like that the FFH PCM "learns" your preferred routes and is continuously optimizing your vehicle's performance to making it better, more fuel efficient. I noticed that when I was doing my first 10k mile break-in; before the PCM got reflashed/reprogrammed with the PCM update.

 

These are all summer numbers no winter driving yet.

 

Yeah...I noticed that before as well that it looks like that with the fan running on low (i.e. lowest setting, no A/C), it sometimes gets better fuel economy than if that was left off. I haven't been able to study the correlation in detail yet (or test the hypothesis); but there's some preliminary data to suggest that that might be the case. (The trick then is to find out the environmental conditions under which the hypothesis WOULD be true.)

[hybridbear]

Interesting data on the trip length. One additional factor in trip length calculations is starting and ending charge. On shorter trips you will get wild swings in trip MPG shown by the computer at the end because the variation in starting and ending charge gives you either extra energy that isn't accounted for in your gallons used (i.e. ending with a lower SOC) or penalizes you for gas burned when that energy wasn't used during the trip (i.e. ending with a higher SOC).

 

Either way, very interesting! Thanks! :stats:

[majorleeslow]

Thanks for the feedback.

 

alpha754293 "Are the number of trips the number of times you've done that particular trip in order to give you the total?"

These are all random trips as needed (No order to the data) done by me (mainly), All types of driving conditions (dry weather, rain etc) different routes, distances, hills, highways, multiple people, different load conditions, different temps. Snow data with heater and heated seats "ON" to come soon :).

 

They are each and every trip that I have done since Mid August till date. The data is compiled from photographs of the "Trip summary" and a record of the time temp and load condition for that trip. I plan to keep doing this until I have a more stable average of each trips as the SOC does throw the number off by a lot on short trips as HB suggests.

 

 

alpha754293 "(The trick then is to find out the environmental conditions under which the hypothesis WOULD be true.)"

 

I do have temp data but its ranging from 58F to 100F which is still summer range and pretty flat line without any interesting trends. And yes keeping the same variables would definately give results quicker but in the long run the all the noise variables should average out.

 

And I believe the fan running on Low definately has a positive effect on mpg. Not sure why but it is very consistent in many readings (city mostly). May be the fan doubles up as battery cooler and/or tricks the system to turn off the environmental controls. Or may be its helping with the way air flows around the car at city speeds. I would surely love to know why. :headspin:

Edited September 17, 2013 by majorleeslow

[majorleeslow]

Interesting data on the trip length. One additional factor in trip length calculations is starting and ending charge. On shorter trips you will get wild swings in trip MPG shown by the computer at the end because the variation in starting and ending charge gives you either extra energy that isn't accounted for in your gallons used (i.e. ending with a lower SOC) or penalizes you for gas burned when that energy wasn't used during the trip (i.e. ending with a higher SOC).

 

Either way, very interesting! Thanks! :stats:

 

Thanks for the feedback

 

Sure the Start/End SOC would be a factor in the MPG. However due to the "Bar" (analog/subjective) nature on the dash I decided to wait to see trends with the ones I could put my finger on with certainty.

 

Think of it this way - how many miles can I drive with a full SOC gage? mmm may be 0.5 mile (may be more - I have some hills which prevent more). and my usual trips are atleast 5 miles long. which could be <10% of noise due to SOC. But theres no way to tell for sure if its at 25% or 75%, it would be based on my judgement at the time. And if I drive the same trip more then once at random occasions the actual number would be apparent after a while as it averages out.

 

For me the bigger thing was to know how the general behaviour of the car is in certain specific conditions. As in what not to do and what to expect if you do certain things. So now I have a general idea of load effects. Next stage would be to tap into the brain of the car (ScangageII). :rockon:

Edited September 17, 2013 by majorleeslow

[alpha754293]

Thanks for the feedback.

 

alpha754293 "Are the number of trips the number of times you've done that particular trip in order to give you the total?"

These are all random trips as needed (No order to the data) done by me (mainly), All types of driving conditions (dry weather, rain etc) different routes, distances, hills, highways, multiple people, different load conditions, different temps. Snow data with heater and heated seats "ON" to come soon :).

 

They are each and every trip that I have done since Mid August till date. The data is compiled from photographs of the "Trip summary" and a record of the time temp and load condition for that trip. I plan to keep doing this until I have a more stable average of each trips as the SOC does throw the number off by a lot on short trips as HB suggests.

 

 

alpha754293 "(The trick then is to find out the environmental conditions under which the hypothesis WOULD be true.)"

 

I do have temp data but its ranging from 58F to 100F which is still summer range and pretty flat line without any interesting trends. And yes keeping the same variables would definately give results quicker but in the long run the all the noise variables should average out.

 

And I believe the fan running on Low definately has a positive effect on mpg. Not sure why but it is very consistent in many readings (city mostly). May be the fan doubles up as battery cooler and/or tricks the system to turn off the environmental controls. Or may be its helping with the way air flows around the car at city speeds. I would surely love to know why. :headspin:

 

You are very welcome.

 

The reason why I asked if it was the same trips to the same places over and over again (for reliability and repeatability reasons). But if they're random trips under those operating conditions (whereby you use what you use as necessary); then it's definitely interesting.

 

Re: SOC - yeah...unless you have a plugin hybrid, it's going to be harder to control that. What I would suggest is to find out what's the greatest variability you would see as a function of SOC, and then knowing that, you would be able to add error bars on your mpg to account for variations in SOC. If I had to do it, that's probably how I would do it.

 

re: fan

I'll have to do more testing with that. I might be able to ask around in our thermal and aero engineering groups here at my building for some additional insights; and maybe be able to get some feedback on that, but if what you're seeing is that it's helping you increase your fuel economy; by all means, why the heck not? :o)

 

I might have to play with that a bit as well.

[hybridbear]

I've found on a common trip we drive of 6.6 miles that the beginning and ending SOC can swing gas mileage from being in the low 40s to mid 80s. We typically average about 57-60 MPG. A couple times where I've started with a low SOC and ended with a high SOC I've seen the trip MPG between 40 & 45. A couple times where I've started with a high SOC and ended with a low SOC I've seen the MPG get up to 80+. All these trips are without air conditioning.

 

I don't think the radio would have much impact. Based on my testing with the ScanGauge the radio draws less than .5 amps. Granted, I don't have the volume set very loudly, if the volume is cranked it would draw more power.

[B25Nut]

 

I've found on a common trip we drive of 6.6 miles that the beginning and ending SOC can swing gas mileage from being in the low 40s to mid 80s. We typically average about 57-60 MPG. A couple times where I've started with a low SOC and ended with a high SOC I've seen the trip MPG between 40 & 45. A couple times where I've started with a high SOC and ended with a low SOC I've seen the MPG get up to 80+. All these trips are without air conditioning.

This is solid evidence that Ford needs to have a plug-in option for their non-Energi hybrids so that the SOC can be topped off overnight, along with heating the coolant. They need to be the first to offer it before Toyota does.

[hybridbear]

This is solid evidence that Ford needs to have a plug-in option for their non-Energi hybrids so that the SOC can be topped off overnight, along with heating the coolant. They need to be the first to offer it before Toyota does.

I agree completely! This would be a great idea for a future improvement. I hope Ford is listening.

 

Another great idea that I'd like to see take off is the solar roof option Toyota offers on the Prius. For those who aren't familiar, a solar panel powers a fan which keeps the air inside the car cooler on sunny days. You can also push a button on your remote to start the A/C before entering the car on those vehicles. The improvement I'd like to see to that offering is for the A/C to run off the solar panel too.

[murphy]

The improvement I'd like to see to that offering is for the A/C to run off the solar panel too.

No panel available today, that would fit on the roof of a car, is going to provide 1kW let alone 5kW.

[majorleeslow]

I believe AC takes under 2Kw. but Even 1 kw could offset the SOC during non driving time when it's sitting in the lot under the sun.

[murphy]

I believe AC takes under 2Kw. but Even 1 kw could offset the SOC during non driving time when it's sitting in the lot under the sun.

My A/C takes 5 kW when starting out in a hot car.

[majorleeslow]

My A/C takes 5 kW when starting out in a hot car.

5 KW wow!- I usually just keep it at Ext temp (-) 5 Deg (thanks to the FFH Forum tips). And then crank it lower as the interior cools down further which keeps the energy consumption lower and mpg's higher. I haven't noticed more than 2Kw consumption so far. Granted we didn't see more than 100F temps this summer.

 

Just thinking in terms of energy needed to propel forward once at speed for 50mph is around 1-1.5Kw.

5KW on the engine consumption scale is the end of red line on Empower (or in the yellow area in our case).

Why would Ford design a car that does that?

[majorleeslow]

 

You are very welcome.

 

The reason why I asked if it was the same trips to the same places over and over again (for reliability and repeatability reasons). But if they're random trips under those operating conditions (whereby you use what you use as necessary); then it's definitely interesting.

 

Re: SOC - yeah...unless you have a plugin hybrid, it's going to be harder to control that. What I would suggest is to find out what's the greatest variability you would see as a function of SOC, and then knowing that, you would be able to add error bars on your mpg to account for variations in SOC. If I had to do it, that's probably how I would do it.

 

re: fan

I'll have to do more testing with that. I might be able to ask around in our thermal and aero engineering groups here at my building for some additional insights; and maybe be able to get some feedback on that, but if what you're seeing is that it's helping you increase your fuel economy; by all means, why the heck not? :o)

 

I might have to play with that a bit as well.

 

Yes on random trips without temp, traffic conditions and SOC data. Which tells me that the loads have a much larger effect than I anticipated. I found it very interesting and hence had the urge to share with the rest of the FFH gang. It would be nice if Myford shows the SOC in terms of Watt hours number instead of a batt gage.

 

To HB's point I've plan to note down the SOC using a scangage (hopefully this holiday season) and will share how much effect that has when there's enough.

 

Do share if you can on what your Aero/Thermo experts inform it should be interesting. May be over the weekend I'll try to find where the fan vent goes through.