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Discussion Starter #1
I saw in the Gen 1 forums that Hold mode won't regenerate above the point where Hold mode was turned on. My question is will Hold Mode in the Gen 2s regen above the hold mode turn on point? I'm asking because I have an upcoming trip where the first 90 miles is predominately highway with varying stretches through small to medium sized towns. My plan is to use Hold between cities and towns and EV in the towns. Will I be "loosing" EV max range doing this or should I switch to Mountain mode to keep a minimum of 40-45% EV range for off-highway sections such as rest areas and gas stops?
 

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My understanding is that Hold mode won't substantially regen the battery at all beyond what you might get with braking. This is apparently unlike the Gen 1 car.
 

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All Volts will regenerate above the hold point, you'll see it as a green bar above the initial hold setting. But they won't keep the extra battery capacity unless you go out of hold and then put the car back in hold, which will then keep the new setting. Otherwise, the car will use up the added range immediately before starting the engine to maintain initial setting.

I have often regenerated my 2013 up to as high as 60 miles (upper limit of its range) when coasting down a mountain pass, then put it in hold. The 60 miles is a fantasy though, you won't really get it.
 

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Any regen you get while driving in Electric Mode will, when used, be counted as Electric Miles. Any regen you get while driving in Extended Range Mode will, when used, be counted as Gas Miles. You get just as much regen when driving down a hill in Hold mode as you do in Normal mode, but it later gets credited as Gas Miles, not Electric Miles. This is normal accounting, because regen power increases the efficiency of the driving mode.

If you drive down a hill in Hold mode, the green bar will go above the initial Hold setting. Apparently, some people have discovered that you can then switch to Normal and then back to Hold to reset the Hold to the new, higher level. When you later switch to Normal and use that regen power, it will now count as Electric, and not as Gas Miles, and so your total trip Gas Miles will diminish by that number of miles, decreasing your MPGcs (gas mileage when using gas). It could also be that when using that particular regen power, the kWh Used will not increase (i.e., it is not grid power being used), and your trip Electric Miles and trip kWh/mile numbers will be artificially inflated.
 

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I saw in the Gen 1 forums that Hold mode won't regenerate above the point where Hold mode was turned on. My question is will Hold Mode in the Gen 2s regen above the hold mode turn on point? I'm asking because I have an upcoming trip where the first 90 miles is predominately highway with varying stretches through small to medium sized towns. My plan is to use Hold between cities and towns and EV in the towns. Will I be "loosing" EV max range doing this or should I switch to Mountain mode to keep a minimum of 40-45% EV range for off-highway sections such as rest areas and gas stops?
As the name implies, Hold Mode holds the current battery state of charge.

For longer trips, I usually use Hold Mode for highway cruising and save the EV mode for traffic plus non-highway driving, then use up the EV mode toward the end.

If my EV miles are very low and I have mix of highway plus urban driving left, I'll often use Mountain Mode to charge the battery during highway cruising. This way city dwellers don't have to be subjected to the noise of my ICE. It also annoys me when the ICE starts and stops frequently in urban driving.
 

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All Volts will regenerate above the hold point, you'll see it as a green bar above the initial hold setting. But they won't keep the extra battery capacity unless you go out of hold and then put the car back in hold, which will then keep the new setting. Otherwise, the car will use up the added range immediately before starting the engine to maintain initial setting.

I have often regenerated my 2013 up to as high as 60 miles (upper limit of its range) when coasting down a mountain pass, then put it in hold. The 60 miles is a fantasy though, you won't really get it.
This.... I wish GM had a Hold+ mode which automatically changed the hold point upwards when you regen. Better yet, add a charge mode that works like mountain mode lite to charge the battery all the way up over say a span of 50 miles or so on ICE.
 

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Discussion Starter #7
Thanks for all the responses. This gives me something to think about. Since the owners manual very clearly states the Volt can't recharge the batteries on ICE this makes me think that the car can recharge on ICE but in order to meet some EPA requirement it doesn't do so.
 

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Thanks for all the responses. This gives me something to think about. Since the owners manual very clearly states the Volt can't recharge the batteries on ICE this makes me think that the car can recharge on ICE but in order to meet some EPA requirement it doesn't do so.
In flat IL you can't recharge on ICE, but if you have lots of hills you can game the system to do so. It's just not designed to do this. I don't think it's an EPA thing. It's an efficiency thing. There are losses in converting momentum into battery energy, then back into momentum. You are really better off just using up the battery and driving on ICE the remainder of your long trip. Trying to opportunistically recharge your battery doesn't gain you much if anything at all in the grand scheme of things.
 

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I went fishing yesterday in Tillamook Oregon via Highway 101 with our 2016 Volt. Total trip was 135 miles. On the way back I had to climb 3 hills. I had 5-6 miles of electric when I began. When I climbed the hill on gas I then placed in hold and at the bottom back into gas. By the time I was about 10 miles from home, I had 10 miles of electric range, I placed the Volt in normal (electric) and finished with 1-2 miles left. Its a good thing I did, as the Memorial Day traffic from Portland Oregon was backed up a good three miles at a crawl. I went 70 miles on electric and the rest on gas, gas was 52 mpg. It was less money to take the Volt than our 2010 Prius. The Prius, 135 miles, 55 mpg, 2.45 gal's used @ $2.579/ gal =$6.31. The Volt, full charge 16 KWH, $1.80 (all cost taxes, fees, delivery charge, everything) 65 miles on gas 1.24 gals @ 2.579=$3.20 + $1.80 = $5.00, savings of $1.31 over the Prius.
 

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For longer trips, I usually use Hold Mode for highway cruising and save the EV mode for traffic plus non-highway driving, then use up the EV mode toward the end.
This sounds like the best advice. And no need to be obsessive about it.
 

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In flat IL you can't recharge on ICE, but if you have lots of hills you can game the system to do so. It's just not designed to do this. I don't think it's an EPA thing. It's an efficiency thing. There are losses in converting momentum into battery energy, then back into momentum. You are really better off just using up the battery and driving on ICE the remainder of your long trip. Trying to opportunistically recharge your battery doesn't gain you much if anything at all in the grand scheme of things.
One special case, however, is traffic. On my more normal commutes, there are two paths I can take: short and long. On average traffic days, the short path wins in terms of time and energy spent. However, there are occasinally bad traffic days where if I take the long route, I both driver farther and slower (non-freeway speeds) heading home. Benefit is since there's already bad traffic, the long way actually gets me home sooner and charges my battery so I actually drive more EV miles cause I'm going down hill so much.
 

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Discussion Starter #13
In flat IL you can't recharge on ICE, but if you have lots of hills you can game the system to do so. It's just not designed to do this. I don't think it's an EPA thing. It's an efficiency thing. There are losses in converting momentum into battery energy, then back into momentum. You are really better off just using up the battery and driving on ICE the remainder of your long trip. Trying to opportunistically recharge your battery doesn't gain you much if anything at all in the grand scheme of things.
Got it. Here's the route profile for the first 87 miles:

Home to Limon.jpg

The first major peak is Castle Rock, CO. After that the towns are in the valleys.
 

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Thanks for all the responses. This gives me something to think about. Since the owners manual very clearly states the Volt can't recharge the batteries on ICE this makes me think that the car can recharge on ICE but in order to meet some EPA requirement it doesn't do so.
To be clear, the driver’s manual is trying to say the ICE doesn’t recharge the battery in Extended Range Mode, not that it can’t.

The ICE only runs the generator as needed to generate electric fuel for the primary motor and to maintain the existing battery state of charge. That second motor/generator under the Volt hood is capable of fully recharging the battery much faster than the L2 level, but, for most owners, it’s much cheaper to recharge at home from the grid. It also keeps the Volt’s use of gas to a minimum. That’s why the system is not configured to recharge the battery in Extended Range Mode.

Mountain Mode is a special exception - if needed, your generator could recharge your battery to the MM-maintained SOC level (~4 bars for Gen 1, ~2 bars for Gen 2) before heading into the mountains, allowing you to avoid a lengthy stop to recharge from the grid.

In one sense, it’s too bad GM didn’t offer the option of enabling the driver to use the gas generator to fully recharge the battery. The Volt could have then been marketed as an electric car to those who have no recharging opportunities at home or at work or as an alternative to using grid power - just drive in "recharge" mode for less than an hour, using under one gallon of gas, and your fully recharged Gen 2 battery contains enough power to drive ~53 battery miles!

The problem with that, however, is that "Electric Miles" are defined as miles driven using grid power from the battery. How would you identify distances driven on gas-generated recharged battery power? If you could fully recharge your battery while driving home with the ICE running one day, would you be satisfied with seeing the 53 battery-powered miles you drove the next day recorded as "Gas Miles" because they weren’t driven on "grid" electricity... or with seeing your "start of day ev range estimate" read "0 miles" because the battery was full of gas-generated electricity, not grid power?
 

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The real advantage, in my opinion, to building up extra electric miles or keeping 10 miles or so of electric in reserve is for those times of traffic jams and highways that turn into parking lots with congested traffic from a crash or another reason. After a while you can get a pretty good feel when you can make the switch from hold mode to normal, electric mode, when your a few miles from home. Usually we arrive with 0 miles of range of 1-2 miles left. In summer with dry roads in temps over 55 degrees you can go a long way in city driving on just 5 miles or so of electric range.
 

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The real advantage, in my opinion, to building up extra electric miles or keeping 10 miles or so of electric in reserve is for those times of traffic jams and highways that turn into parking lots with congested traffic from a crash or another reason. After a while you can get a pretty good feel when you can make the switch from hold mode to normal, electric mode, when your a few miles from home. Usually we arrive with 0 miles of range of 1-2 miles left. In summer with dry roads in temps over 55 degrees you can go a long way in city driving on just 5 miles or so of electric range.
I find that in the winter time after driving hold mode on the highway, when I switch to normal mode for city driving, I can go 6 or 7 miles and not cause the guessometer to lose any range at all.
 

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Discussion Starter #17
I'm seriously impressed!

I took a 60 mile trip to two REIs in Denver today. Between them I put the car in Hold mode and watched it tool along at 70+ MPG driving north on I-25. Northbound is slightly downhill so I expected better than 42 MPG but not that high. I left Hold mode on too long, however, as I got home with 8 miles left on the batteries, and this was running the A/C on automatic temperature but a lower blower speed.

I'm already starting to wonder if GM has underrated the Volt's EPA estimates, just like it underrated the Gen 1 Cruze ECO Manuals.
 

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My understanding is that Hold mode won't substantially regen the battery at all beyond what you might get with braking. This is apparently unlike the Gen 1 car.
Regeneration works the same as in normal. Hold mode runs the engine to keep the battery state of charge at the same level as when hold was activated. (plus/minus a buffer or tolerance amount.)
 

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My understanding is that Hold mode won't substantially regen the battery at all beyond what you might get with braking. This is apparently unlike the Gen 1 car.
Charging during braking is dozens of times more powerful than charging from the engine. Full regenerative braking is upwards of 60 kW, whereas normally the engine, when running solely to charge the battery, doesn't exceed ~5-10 kW at most
 

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Charging during braking is dozens of times more powerful than charging from the engine. Full regenerative braking is upwards of 60 kW, whereas normally the engine, when running solely to charge the battery, doesn't exceed ~5-10 kW at most
Yeah, but you can only do those high KW charges in spurts. If you could find a way to do it for a long time, I'll bet the car would protect the batteries from getting too hot and frying.
 
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