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It's MPGe folks, not MPG for a hybrid!


Robert Burke
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I hear all the chatter about C-max poor gas milage and how people are disappointed!  But, they never stop to consider, that it's both a gas/EV car.  You could care less what kind of MPG you are getting,

you should care more about what kind of EV you are getting, cause that is the only thing that matters!

 

You go to trip and look at your gas milage, then add your EV milage, then divide by fuel used to

get your MPGe, which is your true fuel/EV economy.  Get it?

 

MPG+EV/gallons used=MPGe   I think you will be surprised.   

 

You have to add on the milage the car was driven on BATTERY or EV, to MPG, to get your true MPGe.  

 

Stop thinking the C-max is a gas car, it's battery car with an engine backup.  

 

And use the see-saw method for better fuel economy.  I'm getting 60-70 MPGe!  Happy, happy.

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You're confusing the C-Max hybrid (this forum) with the C-Max Energi plug-in which does get some of motive power from a/c electricity off the grid.  The hybrid gets 100% of it's motive power from gasoline.  It stores some of that force in the form of electricity in the large HV battery.   None of it comes from the grid.  

 

Another way to look at it:  electricity isn't a fuel.  It's simply a carrier/transmitter of power generated by another source (coal, wind, sun, oil, nuclear, etc) and in the case of hybrids; gasoline.

Edited by fotomoto
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Greetings and welcome

Robert

 

As you can see there are a lot of knowledgeable people on this forum.

 

Here's what I tell friends when they ask about MPGe(quivalent)

 

The equivalent formula comes from the EPA, it converts the amount of electricty put into the Energi battery at a plug in station (the 110/220 AC plug in your garage) to the distance that could be driven on a gallon of gasoline.

 

hope this helps

wab

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Energy is energy. The form doesn't matter. If you're driving a plug-in, you're right, as others have noted, to add the miles traveled only on plug-in battery charge to those traveled on gas/battery.

 

If you're driving a hybrid, all your energy comes from gasoline. This graphic helped me see how things interrelate as you move energy from the gas tank into the other three forms a hybrid uses.

post-1320-0-44596600-1383751556_thumb.jpg

 

Have fun,

Frank

 

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BOY!  A lot of smoke here... So, you folks are saying miles driven on battery or EV is not MPGe?  

Then, what the hell is it...smoke?  

 

MPG=miles driven on GAS.

    EV=miles driven on BATTERY

MPGe=total miles driven on gas+battery.   

 

Simplify.  Now, I've got this all figured out in my head, but you guys are turning the screws.   This make sense to me. 

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MPG in a hybrid:    miles the car is driven; this does include the EV miles of course, as all the display modes show.  To paraphrase others' replies to Robert Burke, the gasoline is the only source of energy.  So you (still) divide miles driven by gallons used to get MPG.

 

 I've had a nice run of MPG, hovering around 52.5 because I'm driving relatively slowly in a hilly (and warm) region.  But, the outside temps. are dropping and this will ruin it all.  Are you ready for winter?  cold motors, more rolling friction, more air resistance, . . . maybe only 36 mph until Spring returns.  Good luck, all.

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I had a few minutes yesterday and did some research on Mr. banned Burke, thinking he was a troll.

He's not, found him on Facebook he's been calculating his "MPGe" wrong for several months.

He thinks he's been getting 60+ MPG when really getting less than 40 for months.

His "see-saw method" comes from high tech camera optics "Application of the see-saw method to all refracting optical systems". Fotomoto may find him in camera related searches, I did.

His "grapheme nano-supercapictor" is really spelled graphene supercapacitor.

 

May I suggest that a moderator lock a couple of his threads with a disclaimer, they could be confusing if found in future searches.

 

Maybe send him an email explaining that "Pulse and Glide" and MPGe are well established terms.

Maybe??? offer him probation with each of his future posts being checked by a moderator????

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We all come here with varying states of understanding, all imperfect in some regard. The forum discussions promote investigation and finding what's actually happening; we get a chance to learn. I see no reason to treat the more obstinant learners poorly just because they take a while to get it. As long as a thread resolves into accuracy, I see no reason to lock them as the misunderstanding may be commonly held, and so its resolution good reading.

 

Conversely, trolls should be beaten with a stick until dead. It can be hard to tell the difference at times... let's err on the side of patience as trolls will out themselves.

 

Do we have a glossary thread, or just links to hypermiling sites for that?

 

Have fun,

Frank

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If the mods did that, then it would be considered censorship. Right now I see no need to lock anything otherwise wab and Frank could not have replied and I would rather see this thread naturally expire like any other thread. 

 

In regard to Mr Banned Burke, I certainly issued the warning point with no banzor action and this morning, site admin had him banned. Perhaps something came up in the IP check, I dunno. 

 

Carry on...or should I now say see-saw on....

 

Is it me or isn't it rather delusional to use MPGe because it produces a somewhat higher number? C'mon as much as the CMax has the EV motor, it ain't the primary motor like in a Volt and MPG seems more appropriate. Jus my 2c.

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If the mods did that, then it would be considered censorship. Right now I see no need to lock anything otherwise wab and Frank could not have replied and I would rather see this thread naturally expire like any other thread. 

 

In regard to Mr Banned Burke, I certainly issued the warning point with no banzor action and this morning, site admin had him banned. Perhaps something came up in the IP check, I dunno. 

 

Carry on...or should I now say see-saw on....

 

Is it me or isn't it rather delusional to use MPGe because it produces a somewhat higher number? C'mon as much as the CMax has the EV motor, it ain't the primary motor like in a Volt and MPG seems more appropriate. Jus my 2c.

 

 

Maybe it was the nasty language he used or him also saying "I'm out of here" and "BYE" in the post that contained the nasty language (in the "Why hybrids often deliver lower mpg than advertised" thread).

 

With respect to using MPGe for a non-plug-in hybrid - I would not say it is delusional, I would just say it is wrong because the only way to add "external" energy to a non-plug-in hybrid is by putting gas in the tank - so all that is needed and appropriate in the denominator (i.e., after the P for per) is G for gallons of gas.

 

I don't have an Energi so I don't know all the ways in which it calculates and displays info on miles traveled per "external" energy added to the vehicle. 

 

For a plug-in-hybrid like the Energi there are two ways to add "external" energy - [a] putting gas in the tank and putting energy into the battery by plugging the car into a power source (charger).

 

I think there are three ways to look at miles per "external" energy input for a plug-in-hybrid. 

 

[1] Looking at the car operating in electric only mode.  In this case, the Ge is based on a calculation which converts electrical energy put into the battery by plug-in charging into equivalent gallons of gasoline.  I think an example of this is the high (100+) number on the sticker on the Energi.

 

[2] Looking at the car operating in both electric only mode and hybrid (i.e., combination of gas and EV) mode and including gasoline usage plus energy put into the battery by plug-in charging (equivalent gallons of gasoline) in the denominator.  I don't know how/if the Energi reports this and whether it is also referred to as MPGe.

 

[3] Looking at the car operating in both electric only mode and hybrid (i.e., combination of gas and EV) mode and taking only gasoline usage into account in the denominator.  I don't know how/if the Energi reports this, but it would be easy for the owner to track this manually, on a spreadsheet or in Fuelly (or similar application).  I have seen posters on this forum do this, for example:  [paraphrasing] "Most of my driving with my Energi is done in all electric mode. I only buy gas once a month. I drive 20 miles to work and 20 miles home.  My employer lets me plug-in while I am in the office.  Last month I drove 1,600 miles and only used 12 gallons of gas.  My MPG for the month was 1600/12 = 133.  Woo-hoo!!! [original poster inserts dancing hot dog and other happy emoticons here]"

 

Another way to look at the month described above [per item 2 above] is that the 1,600 miles consisted of 1,000 electric only mode miles and 600 hybrid mode miles.  The 1,000 electric only mode miles would have been made possible by plug-in charging that put electrical energy equivalent to about 10 gallons of gas into the battery.  So total "fuel usage" was the equivalent of 22 gallons of gas [12 gallons of gas plus 10 gallons of gas equivalent.  This gives an equivalent MPG of 1600/22 = 72.7, not too shabby!!!  [original poster inserts dancing hot dog and other happy emoticons here]

 

Note that in hybrid mode this driver got 600 miles on 12 gallons of gas which is 50 MPG - also not too shabby.

 

I would welcome a reply from an Energi owner which explains all of the ways the Energi displays info, what else can be calculated and what can't be calculated from the info displayed.

Edited by DaveofDurham
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The Energi will display MPG and MPGe data. It will not give you EV only miles. It combines all EV and hybrid power into 1 EV mileage reading. That information is available in the trip data and has a volatile

memory. It can be reset. It won't give you a true vehicle lifetime EV mileage reading. It's been eliminated on Job3 vehicles. I think Job3 cars are July 2013 and up production dates.

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The Energi will display MPG and MPGe data. It will not give you EV only miles. It combines all EV and hybrid power into 1 EV mileage reading. That information is available in the trip data and has a volatile memory. It can be reset. It won't give you a true vehicle lifetime EV mileage reading. It's been eliminated on Job3 vehicles. I think Job3 cars are July 2013 and up production dates.

 

I don't like that they took away a lifetime figure that was in the early vehicles.

 

I think telling you miles driven in all electric mode would be a nice feature.  If the Energi provided this figure then it could be subtracted from total miles to get miles in hybrid mode which could then be divided by gallons of gas used to get a hybrid mode MPG figure for an Energi that could be compared to what drivers of non-plug-in C-Max are achieving.

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Since I got an Energi I was at 999.99MPG because I was always on EV. I switched to MPGe so I could get a relatively accurate accounting for mileage. My current tank of Gas is at 145.3 MPGe while the lifetime of the car is 105 MPGe ( I don't know who was driving the car at the dealership but those first 32 miles were horrible in MPG.) It is useful to me now that I have the Energi, when I had the hybrid it made sense to use MPG as I was always using the ICE for charging the hybrid battery.  Just my 2 cents.

 

Peace,

 

Fr. Bill

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As we transition away from the conventional ICE-powered automobile I have thought that the traditional MPG measurement of efficiency is outdated. I would like to see a much more technical measurement that captures the car's true efficiency.

 

Energy input into the car via gasoline, diesel (internal energy of a certain volume of liquid) or electric would be measured in joules. On the output side the energy used by the car for propulsion, climate control, rolling the windows up and down, etc. would be tracked. The output divided by input gives an efficiency that ignores other factors that make MPG misleading.

 

The trick with this method, I believe, is somehow having the auto track the energy coming in and going out. I also think this is such a radical departure from the existing method that consumers would be more confused than helped.

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MPG is outdated; the rest of the world looks at fuel consumption, liters per 100 kilometers. Since we American's are outdated elsewhere as well, it's gallons per 100 miles.

 

You're thinking in a useful direction, but not a practical one.

- the energy coming in depends on the quality of the gasoline; how does the car know if you got good gas?

- energy drains vary dramatically based on road speed (known) and air speed (unknown), terrain (unknown) and driver intent (unknown to the car).

 

With gaps on both sides of the equation, you can see why no one offers a true efficience meter. Add in the need to know the price of fuel in the tank and you can see this is far from practical...

 

But an interesting topic. What I find is that MPG is a good coorrelate for efficiency over a limited range, and that fuel consumption removes the limitations, even as we continue to use the familiar but outdated metrics.

 

Have fun,

Frank

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MPG is outdated; the rest of the world looks at fuel consumption, liters per 100 kilometers. Since we American's are outdated elsewhere as well, it's gallons per 100 miles.

 

You're thinking in a useful direction, but not a practical one.

- the energy coming in depends on the quality of the gasoline; how does the car know if you got good gas?

- energy drains vary dramatically based on road speed (known) and air speed (unknown), terrain (unknown) and driver intent (unknown to the car).

 

I never said my suggestion was perfect and I agree that capturing that data would be difficult. My purpose was to use a system that focused more on the car itself rather than the variables of the people driving it.

 

For example, consider a conventional automobile that sits at idle (consuming very little non-engine energy) and the same model that is moving down the road. According to our present system the first one has a much lower MPG than the second simply because of the difference in miles traveled. In my proposal the car's efficiency is determined by the work it does when it is operated as intended.

 

Granted, because of the challenge in getting the data this is more of a thought experiment than an actual feature request.

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I don't like that they took away a lifetime figure that was in the early vehicles.

 

I think telling you miles driven in all electric mode would be a nice feature.  If the Energi provided this figure then it could be subtracted from total miles to get miles in hybrid mode which could then be divided by gallons of gas used to get a hybrid mode MPG figure for an Energi that could be compared to what drivers of non-plug-in C-Max are achieving.

I plan on using trip 2 with a logbook to keep track of my total EV miles. I plan on using my trip 2 data to keep track of ICE miles.

That way, I can change my oil every 5K or 6 to 8 months. I don't plan on letting my oil go past either of those parameters.

I'll just reset trip 2 every 5K of ice time. Kinda like an oil life monitor.

 

Oil contains acid's that can and will cause damage to seals that will lead to oil leaks. It's not worth saving 20 bucks to have oil leaks.

Edited by drdiesel1
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