ICE mileage

  • Thread starter Thread starter JKroll
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JKroll said:
Thanks for everyone's concern regarding speed. I am not a very fast driver so chill. The speed limit is 70 here so I was mostly in 70-75 range.
But I did try going around 80 in some patches.
I have only one ticket on my old CRV driving at 45 in 35 mile zone. Funny thing is I rarely drove this car fast since it was big and not very sleek for quick acceleration.

Cold weather would have some effect . Also my tire pressure were low .. indicator came on after we completed the trip. It was around 32 in all tires.

The 55 I saw was in earlier reviews etc. Maybe that included using the EV mode. I avoided using the EV mode since I wanted to have a ICE mileage number.

If accord gives 38 on highway what would be clarity's advantage.
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Hey JKroll... ignore the sensitivities in this board - some here only want to hear great things and not a slight on Clarity the "chariot of gods"

With that said, ambient temperature, climate control (in the 30s I'd guess you used the heat and maybe some defroster/defogger), speed, tire pressure, heavy acceleration/deceleration, uphill or flat terrain... and on and on will cause variations on the mpg.
IMO, Clarity is ideal for urban or suburban daily use of commuting to work no more than 30miles total, taking kids to school, groceries and weekend chores. It does that very well with great efficiency where its size comes handy and one can go months without the need to refuel.

For other purposes, like excessive commutes and long trips is just another midsize sedan with respectable mpg (one has to take a chill pill and listen to KennyG) , mediocre noise level comfort (my opinion, when considering ICE and road noise felt in the cabin on highway driving), and average driver experience when it comes to cabin comforts and luxuries. The advantage over hybrid Accords and Camrys of the world (local EV mode benefits asside) is the hefty federal and sometimes state tax rebates that make this vehicle much cheaper when all said and done.

Cheers
 
JKroll said:
ClarityBill - this is interesting take "It looks like he went to HV mode with a fully charged battery: At cold temperatures, it has trouble staying in gear mode with a full battery."

I dont know what gear mode is. So you are saying I should have started in EV mode and let the car do what it wants rather than having a full battery and forcing it to run ICE engine with HV.

On next trip I will try that. I wanted to get a mileage for ICE engine and all of you are saying this is not the right way to do it ?
And almost all of you have got better mileage than me.

I am going to read up some other threads on this forum.
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The "gear" mode is when the clutch locks up the ICE with the drive gear. Because this is a single speed transmission with a ratio similar to the highest gear on regular ICE cars, the clutch only engages when the speed is above 45 mph or so. Even then, it only engages when it is most efficient to do so. The "gear" everyone speaks of is the little white symbol that shows up in the dynamic energy flow diagram of the 8 inch screen (or dash) if you select to display it. The gear appears between the front wheels in the diagram when the clutch engages.

I disagree with the idea that one should deplete the battery and let the car go to HV mode on its own during long drives. The battery can provide up to 120 hp on its own but to get 180 hp, you need the combined efforts of both the ICE and the battery. Once the battery is depleted, the car relies on the ICE to generate all the electricity. This is where others (and from my experience) have reported very high revving of the ICE with very limited power so you'll have a hard time climbing an extended upgrade on a depleted battery or when you need extra power to merge or pass. I keep my battery at about 60-70% in HV mode (not full) so I can call on the full 180 hp (or the elusive 212 hp) when I need it.
 
JKroll,

This is my opinion on how to get better gas mileage.

If you are travelling farther than EV mode, you want to 'force' it run the ICE engine with HV at the right time... Switch to HV mode with about half the battery left. Don't switch to HV mode with the fully charged battery, and do not let the battery go all the way to zero. The car will take the battery to zero if you don't do anything.

Switch to HV mode later with colder temperatures (less than 30% battery below 40F), but do not let the battery go to zero.

If battery gets too low, you can use HV charge mode to bring it up to a nice range. You will have bad gas mileage while in HV charge mode. HV charge will take charge up higher than it needs to be, so you want to switch back to HV mode when the battery is good.

I refer to gear mode because a little gear will show up on the vehicle energy display, at the cross of the supply power and the wheel power. It is a little easier to see on the tablet. - Info - Vehicle energy.

Depending on how much you want to 'manage' the car. You can work to keep it in gear mode. If the car does go out of gear mode, you can force it to go back in by switching out of HV mode, and back in. (Two presses of the HV button, about a second apart). The display should show HV mode off, then HV mode on - or something like that. It may take a few seconds for the gear icon to appear. You will lose some EV range by doing this technique, but it gets the gas mpg back up more quickly. (The car will normally return to gear mode without this technique after the battery recovers, which may take several minutes.)

There are several threads that get into the mechanics of gear mode, if you are interested... or not.
 
ClarityBill said:
JKroll,

This is my opinion on how to get better gas mileage.

If you are travelling farther than EV mode, you want to 'force' it run the ICE engine with HV at the right time... Switch to HV mode with about half the battery left. Don't switch to HV mode with the fully charged battery, and do not let the battery go all the way to zero. The car will take the battery to zero if you don't do anything.

Switch to HV mode later with colder temperatures (less than 30% battery below 40F), but do not let the battery go to zero.

If battery gets too low, you can use HV charge mode to bring it up to a nice range. You will have bad gas mileage while in HV charge mode. HV charge will take charge up higher than it needs to be, so you want to switch back to HV mode when the battery is good.

I refer to gear mode because a little gear will show up on the vehicle energy display, at the cross of the supply power and the wheel power. It is a little easier to see on the tablet. - Info - Vehicle energy.

Depending on how much you want to 'manage' the car. You can work to keep it in gear mode. If the car does go out of gear mode, you can force it to go back in by switching out of HV mode, and back in. (Two presses of the HV button, about a second apart). The display should show HV mode off, then HV mode on - or something like that. It may take a few seconds for the gear icon to appear. You will lose some EV range by doing this technique, but it gets the gas mpg back up more quickly. (The car will normally return to gear mode without this technique after the battery recovers, which may take several minutes.)

There are several threads that get into the mechanics of gear mode, if you are interested... or not.
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Looks like lot of steps to get into right mode so to speak
I dont think my wife can follow so many steps .. at most I can advise her to switch to HV at right battery level.

As for me I want to read up on this gear mode people keep talking about.
 
JKroll said:
Looks like lot of steps to get into right mode so to speak
I dont think my wife can follow so many steps .. at most I can advise her to switch to HV at right battery level.

As for me I want to read up on this gear mode people keep talking about.
Click to expand...
My seven-word technique: Run in HV when on the highway.

When I go on a road trip, I simply press the HV button when I am established on the Interstate, and press it again when I exit. This is my personal preference - I prefer EV mode in city driving, so I want to save my EV miles for that style of driving. I am not obsessive about this, and if I run out of EV range, so be it. The other caveat is that you have to remember to hit that HV button when you re-enter the Interstate after your rest stop.

As for the gear icon . . . I find it much more elusive than most folks here, but I make no effort to coerce the car into using it. When it happens, it happens. The mysterious thing for me is that I can drive the same stretch of highway at the same speed and observe completely different behavior regarding the gear icon . . . sometimes it appears and stays on pretty consistently, and other times it appears rarely or not at all.
 
JKroll,

Sounds like you got the important part:

On a trip, switch to HV mode with 10-20 miles of battery range left.

The rest is in the realm of hypermilers.
 
JKroll said:
If accord gives 38 on highway what would be clarity's advantage.
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Regenerative braking, which means you probably don't need to worry about brake wear until approaching 100k miles. That's a big ev motor advantage. Also 38mpg range on the Accord is generally based on 65-70mph driving.
 
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ab13 said:
Regenerative braking, which means you probably don't need to worry about brake wear until approaching 100k miles. That's a big ev motor advantage. Also 38mpg range on the Accord is generally based on 65-70mph driving.
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Dont have to worry about brakes but have to pay $120 more per year on oil changes. :)
 
JKroll said:
ClarityBill - this is interesting take "It looks like he went to HV mode with a fully charged battery: At cold temperatures, it has trouble staying in gear mode with a full battery."

I dont know what gear mode is. So you are saying I should have started in EV mode and let the car do what it wants rather than having a full battery and forcing it to run ICE engine with HV.

On next trip I will try that. I wanted to get a mileage for ICE engine and all of you are saying this is not the right way to do it ?
And almost all of you have got better mileage than me.

I am going to read up some other threads on this forum.
Click to expand...
No don't do that. I think the consensus here is that somewhere between 10 and 70% charge is ideal for the car. Bring it down to 70%, then go to HV, use up the remaining electric if you wish as you approach home.
 
The Accord is 700lbs lighter, it is mainly the battery in the Clarity. BTW: I consistently get 46mpg at 65mph in HV mode with 50% battery in reserve.
 
Chuck said:
The Accord is 700lbs lighter, it is mainly the battery in the Clarity. BTW: I consistently get 46mpg at 65mph in HV mode with 50% battery in reserve.
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Yep. In the Accord you're lugging around a slightly larger engine for a minimum weight penalty over the Clarity or lugging around a significantly larger battery with a significant weight penalty. I do wonder what would have happened to have they just taken our drivetrain and put it into the Accord (if it would fit) and have had a car a little more marketable. The Clarity has a significant amount of aluminum in it to lighten the weight, but it's also overbuilt since it was designed to lug around hydrogen tanks.
 
I believe highway mileage is much more a function of aerodynamics (drag coefficient * frontal area) than weight. My guess is that the Clarity has a larger frontal area, and probably a slightly better or similar drag coefficient. Those numbers aren't published so it is just a guess.
 
Mowcowbell said:
Other than a few highways in West Texas and Montana where is it legal to drive 80-90 mph?
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Last October, my wife and I did a month long mega road trip from SoCal through Arizona, Colorado, Utah, Idaho, Oregon and back down to home. There were many highways in Colorado, and IIRC in Utah where the posted speed limit was 80 mph. And we did keep at that limit wherever posted.

I kept track of actual gas usage (we ran on HV the whole time). The trip totaled just under 4,000 miles. Our MPG for the trip was 43.6 mpg. I thought that was pretty remarkable considering the speeds and all the mountain driving we did. Not to mention how comfy the car is and how much luggage we could get into the trunk.
 
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