[rotaryenginepete]

I think the regen is much like a CVT transmission. It is for light use and mostly city driving in a small car. It is more assist than braking.

The Bolt I drove offered it but you have to shift to L to get it and that is more a city setting. It drove like a golf cart. It worked but you had to get a feel for it and use good judgment.

No one is going to get run over by a Tesla as they just removed the regen option. That is a sign they had issues as it is being claimed to being reworked or it may just disappear.

Regen works to a degree but it takes some judgment from the driver and too many drivers lack that ability. Also it has limits and I just don’t see towing braking as a major option.

The automakers are going to learn a lot here. Technology is able to do a lot but you still have to rely on the operator to apply it in many cases.

Some smart phones are not too smart in some hands vs others. Same applies here.

In the future regen and electronic brake by wire could be merged. Brake by wire is still pretty new so it may be a bit yet.

I owned a Volt for several years. The brake regen on that car is done through the eCVT, and it works so well I could raise the battery charge a notch going downhill. In L mode it could seriously slow the car down. If you go on the Volt forums several have complained about getting rear ended because the brake lights don't come on when regen braking. But pure EV's don't need the eCVT because, like every other electric motor, their drive motors are also electric generators in reverse.

Tesla removed the option to adjust regen, not the regen feature itself.

I think you missed the concern here which is braking downhill. Exhaust brakes accomplish this so as not to burn up the friction brakes. Given the same load going downhill, a Tesla Semi would also burn up its friction brakes, so it also needs an alternative braking method. The Tesla Semi's regen brakes would not work if the battery was fully charged, because there would be nowhere for the surplus electricity to go.

 

[GraniteBlue05]

It 's the same. If you attempt to drive a 40 ton truck down a long grade using just the foundation brakes, the brakes will overheat and stop working in short order. Then you can either take the truck runaway ramp, or you can attempt to set a new land speed record.

Conventional trucks solve this by using the engine brake. The engine brake puts the energy into air, which exits through the exhaust.

A BEV truck would put the energy into a battery. If the batteries are full, that energy needs to go someplace else.

Maybe when the batteries are fully charged on a large BEV truck . . . a series of 1,000 candle power light panels aimed downward under the rig and on to the road would light up under down grade braking. That could dissipate the energy and also alert other nearby drivers that the rig is near going ballistic when they see the whole undercarriage and road below the rig lit up like an airport landing strip.

Not anymore far fetched than the dubious claims, speculations and imaginings of other sources here or online . . . .

 

[hyperv6]

I owned a Volt for several years. The brake regen on that car is done through the eCVT, and it works so well I could raise the battery charge a notch going downhill. In L mode it could seriously slow the car down. If you go on the Volt forums several have complained about getting rear ended because the brake lights don't come on when regen braking. But pure EV's don't need the eCVT because, like every other electric motor, their drive motors are also electric generators in reverse.

Tesla removed the option to adjust regen, not the regen feature itself.

I think you missed the concern here which is braking downhill. Exhaust brakes accomplish this so as not to burn up the friction brakes. Given the same load going downhill, a Tesla Semi would also burn up its friction brakes, so it also needs an alternative braking method. The Tesla Semi's regen brakes would not work if the battery was fully charged, because there would be nowhere for the surplus electricity to go.

I have read some systems may indicate 100% charge they still have unused capacity to permit the excess power to go some places till more burns off. This will let regen work in full charge mode. That was just one I have seen. Much of the semi stuff is just starting so they are doing things six ways to Sunday right now. I expect a lot of development till they hit the market. I have seen Bosch is even putting regen on trailers.

It makes more sense than some wild concepts I have seen.

With trucks they would have much more battery capacity and more room to pay with the extra capacity. Also I wonder if you could use a regulator to better manage the capacity.

One thing for sure there will be a lot new tech and things we have learned as they bring these thing out.

 

[rotaryenginepete]

I have read some systems may indicate 100% charge they still have unused capacity to permit the excess power to go some places till more burns off. This will let regen work in full charge mode. That was just one I have seen. Much of the semi stuff is just starting so they are doing things six ways to Sunday right now. I expect a lot of development till they hit the market. I have seen Bosch is even putting regen on trailers.

It makes more sense than some wild concepts I have seen.

With trucks they would have much more battery capacity and more room to pay with the extra capacity. Also I wonder if you could use a regulator to better manage the capacity.

One thing for sure there will be a lot new tech and things we have learned as they bring these thing out.

That is exactly where most of the Tesla shills just don't get it with trucks. A BEV truck must give up cargo capacity for battery capacity and range, where ICE, HEV, and FCEV truck does not have that problem. It goes back to the energy density delimma. Lithium ion batteries (and pretty much every type of battery) will never reach the same energy density as a liquid fuel, simply because it's not chemically possible.

 

[hyperv6]

That is exactly where most of the Tesla shills just don't get it with trucks. A BEV truck must give up cargo capacity for battery capacity and range, where ICE, HEV, and FCEV truck does not have that problem. It goes back to the energy density delimma. Lithium ion batteries (and pretty much every type of battery) will never reach the same energy density as a liquid fuel, simply because it's not chemically possible.

Thanks I was not thinking about load rates. I just have not spent a lot of time on the trucks as I see them coming later in the semi’s.I forgot lost cargo weight due to the batteries.

Do you know if Max truck weight is figured with tanks full or empty?

The smaller delivery fleets are just now coming in and I expect much will be learned there. I see in San Diego the Amazon trucks are now. Going electric. I will be interested to see if the try any in the cold states and how well they do.

 

[JeffreyG]

Thanks I was not thinking about load rates. I just have not spent a lot of time on the trucks as I see them coming later in the semi’s.I forgot lost cargo weight due to the batteries.

A lot of trucks load out on volume (think potato chips) before they load out on weight. The guys who will be most sensitive and slow to adapt BEV trucks will be the bulk haulers (milk, gasoline) and especially the speciality bulk haulers (cryogenic liquids).

I would not be so quick to assume that BEV cars will be adapted before trucks. Trucks have one huge thing going for them in pushing to electric, and that is cost. A lot of semi's burn 12,000 to 30,000 gallons of diesel fuel a year. That means if you can find a significantly cheaper fuel (like electricity) then you can find a way to payback a pretty expensive initial cost. Of course, electricity pricing isn't all that simple with demand charges etc.

Other factors at play include maintenance, which is another major cost for semi's. BEV trucks are perceived (probably correctly) as being cheaper to maintain. No oil changes, less filters, possibly lower brake wear.

The first adaptors for BEV will be urban buses (already underway) as they have an ideal use case. There are a lot of regional haul or port drayage trucks that will probably come next. Long haul cross country, vocational, and bulk haulers will be last.

 

[rotaryenginepete]

Thanks I was not thinking about load rates. I just have not spent a lot of time on the trucks as I see them coming later in the semi’s.I forgot lost cargo weight due to the batteries.

Do you know if Max truck weight is figured with tanks full or empty?

The smaller delivery fleets are just now coming in and I expect much will be learned there. I see in San Diego the Amazon trucks are now. Going electric. I will be interested to see if the try any in the cold states and how well they do.

Max truck weight is normally calculated by a drive on scale, so yes. For comparison purposes, the max weight for a Class 8 is typically 80,000lbs.

Diesel:
Some long haul trucks have dual 150gal tanks. A gallon of diesel weighs 7 pounds, so that comes out to 2,100lbs of fuel. The average diesel truck will get around 7mpg with this load, so that range comes out to 2,100 miles.

BEV:
Some journalists have calculated that the Tesla Semi empty weight is about the same as your average diesel semi truck, and that the battery pack for the 500 mile range variant weighs around 16,000lbs...although Tesla hasn't publicly released those details yet.

So there you have the comparison for energy density, a diesel truck needs 500 lbs of fuel and the BEV needs 16,000 lbs of battery to take the same payload the same distance. To increase the range of the BEV means significantly reducing the available payload, which is why you won't ever see long haul team driving in a BEV truck.

 

[hyperv6]

Thanks guys for the info and Not being a snide think they know it all with not so bright ideas!

I have seen the semi stuff but have not really spent much time on it. As for the Tesla semi I really never expected much soon there as Musk is usually over Promising and is Late on many of his projects.

I agree most of this is going to be cost/regulation driven even as they say they are doing it for the environment. As batteries get cheaper the cost of these models drops fast.

 

[rotaryenginepete]

Thanks guys for the info and Not being a snide think they know it all with not so bright ideas!

I have seen the semi stuff but have not really spent much time on it. As for the Tesla semi I really never expected much soon there as Musk is usually over Promising and is Late on many of his projects.

I agree most of this is going to be cost/regulation driven even as they say they are doing it for the environment. As batteries get cheaper the cost of these models drops fast.

One other note: Bosch, Hino, Wrightspeed and others are beginning to offer diesel hybrids for commercial use which cut fuel consumption significantly (over 50%), which degrades the fuel cost savings of a BEV over diesel.

 

[hyperv6]

One other note: Bosch, Hino, Wrightspeed and others are beginning to offer diesel hybrids for commercial use which cut fuel consumption significantly (over 50%), which degrades the fuel cost savings of a BEV over diesel.

I see Bosch is even using the trailers in various ways too with different systems.

I see so much on the autonomous trucks but I see electric trucks of some kind as more likely to be in play.

 

[JeffreyG]

One other note: Bosch, Hino, Wrightspeed and others are beginning to offer diesel hybrids for commercial use which cut fuel consumption significantly (over 50%), which degrades the fuel cost savings of a BEV over diesel.

I'm really skeptical. What kind of drive cycles?

The DOE funded SuperTruck project saw OEMs experimenting with hybrid drive systems in class 8 trucks, and the fuel savings were quite minimal, in the low single digit percentages. Most teams concluded that hybrid drive systems faced very challenging business cases.

 

[rotaryenginepete]

I'm really skeptical. What kind of drive cycles?

The DOE funded SuperTruck project saw OEMs experimenting with hybrid drive systems in class 8 trucks, and the fuel savings were quite minimal, in the low single digit percentages. Most teams concluded that hybrid drive systems faced very challenging business cases.

Well they have moved on to SuperTruck II now. There are studies that project 2/3 of vehicles sold by 2030 will still use ICE. The efficiency gains of diesel hybrids vary widely.

Wrightspeed has been doing diesel hybrid conversions that save up to 60% on fuel, most of their current conversions are on garbage trucks and buses.
They also have a turbine range extender in development:

Hino (Toyota) has had diesel hybrids out for over a decade now, the early versions of this parallel hybrid system produced gains of around 30% fuel efficiency over their non-hybrid versions.

Scania has a diesel hybrids which get 15% fuel economy savings:

5 years ago Bosch unveiled their Diesel Hybrid concept, a series hybrid which at the time only garnered a 6% reduction in fuel consumption. However, that was 5 years ago...since then they have developed a 50% efficient engine with Weichai and have made leaps and bounds with their 48V hybrid tech. Unfortunately, their alleged role in the VW emissions scandal have really put a damper on releasing the technology for production.

Heavy equipment is also moving towards diesel hybridization:

Outlook on the Hybrid Diesel Genset Global Market to 2026 - Featuring AKSA Power Generation, Ascot Energy & Caterpillar Among Others

Dublin, Nov 16, 2020 (GLOBE NEWSWIRE via COMTEX) -- Dublin, Nov. 16, 2020 (GLOBE NEWSWIRE) -- The "Global Hybrid Diesel Genset Market (2020-2026): Market...

www.marketwatch.com

 

[hyperv6]

One thing that cold really kill Hybrid Diesel is the killing of Diesel period. Some cities and countries are already putting end dates to sales. It will come down to the fine print if they will permit Hybrids.

Many of these laws were passed by people that have no mechanical background and don't always use reasoning and sense.

 

[Goodspike]

One thing that cold really kill Hybrid Diesel is the killing of Diesel period. Some cities and countries are already putting end dates to sales. It will come down to the fine print if they will permit Hybrids.

I don't see the point of a hybrid diesel. If it's the type of hybrid where the engine portion shuts down periodically, then that wouldn't be good for the diesel engine (I'm not crazy about that for a gasoline engine either!). If it's a supplement electric motor I'm not seeing the point because diesel engines do not typically need their torque supplemented (although more is better!). Also, since diesel engines tend to weigh more, the added weight of the hybrid system would be an additional burden.

 

[rotaryenginepete]

One thing that cold really kill Hybrid Diesel is the killing of Diesel period. Some cities and countries are already putting end dates to sales. It will come down to the fine print if they will permit Hybrids.

Many of these laws were passed by people that have no mechanical background and don't always use reasoning and sense.

Germany and California are already having big problems with brownouts and energy shortages. Maybe they will change their dumb policies when people start starving to death.

I don't see the point of a hybrid diesel. If it's the type of hybrid where the engine portion shuts down periodically, then that wouldn't be good for the diesel engine (I'm not crazy about that for a gasoline engine either!). If it's a supplement electric motor I'm not seeing the point because diesel engines do not typically need their torque supplemented (although more is better!). Also, since diesel engines tend to weigh more, the added weight of the hybrid system would be an additional burden.

The points are efficiency and reliability.
1. Better efficiency means cost savings from less fuel consumed and less maintenance required. With respect to your stop/start concerns, there are iron oxide coatings developed to mitigate that.
2. Diesel is proven. Electric is proven. Batteries are not. They simply lack the energy density needed to get the big jobs done, which means we cannot rely on BEV's to do everything.

 

[Goodspike]

I think this is new news about GM and Nikola--their dealings seem somewhat fluid right now.

GM walks away from stake in electric vehicle maker Nikola

NEW YORK (AP) — General Motors will not be taking a stake in the electric vehicle...

www.seattlepi.com

 

[JeffreyG]

I think this is new news about GM and Nikola--their dealings seem somewhat fluid right now.

Yeah, GM is an actual company that makes cars and Nikola is selling vaporware. I dunno what Mary was thinking getting on board the clown car.

Back in the old days you had to flee to Argentina with the investor's money in a scheme like this, but these days you can seemingly keep the grift going forever. You get the occasional Theranos, but somebody going to jail there only stands out for how rare it is.

 

[JeffreyG]

2. Diesel is proven. Electric is proven. Batteries are not. They simply lack the energy density needed to get the big jobs done, which means we cannot rely on BEV's to do everything.

I'm not sure I would agree that batteries are 'unproven'. Battery technology has been improving at an incredible pace and all of the doomsaying of the pundit class have been proven wrong. When Honda and Toyota first released hybrids (over 20 years ago!), it was all "Owners will have to replace the batteries at $5000 in seven years." kind of prognostication. Never happened.

Nissan Leaf was derided for the same reason, but a long term rapid charging study of the Leaf finds very slow degradation rates (and this for Leafs used in Phoenix).

I believe several automakers are showing that BEV are on the cusp of practicality for widespread passenger car use. Tesla has already made the case for luxury car markets, and while Tesla price points are still high for mass market, the pace of reduction is good. As much as I cannot stand Elon Musk, his company has been setting the price / profit curve well ahead of what all prognosticators said possible. The HD truck makers are similarly showing plausibility in regional haul / hub and spoke use.

Oddly enough, MD and HD truck are somewhat better applications than pickup trucks. The main challenge with a pickup (or perhaps SUV too) model is that the edge cases are so far from the base case. Start with a car, like a Chevy Bolt. This is a car that is overbuilt for its 90% use case of running one person to work and back daily. But the edge case of a Bolt loaded with 3-4 people and driving over to grandma's for Thanksgiving is not so far away that the full battery capacity stops making economic sense.

But now take a pickup and the 90% base case (carrying one person to work and back) is really far from the edge case (hauling a boat to the lake, or an RV to a distant campground). Enough battery capacity for the edge case winds up being enough for 1000+ miles of driving in the base case, and the vehicle becomes uneconomical.

HD trucks don't have this problem because the base case is the edge case for most - Fully loaded for about as far as a driver can go in the 11 hour driving limit.

 

[rotaryenginepete]

I'm not sure I would agree that batteries are 'unproven'. Battery technology has been improving at an incredible pace and all of the doomsaying of the pundit class have been proven wrong. When Honda and Toyota first released hybrids (over 20 years ago!), it was all "Owners will have to replace the batteries at $5000 in seven years." kind of prognostication. Never happened.

Nissan Leaf was derided for the same reason, but a long term rapid charging study of the Leaf finds very slow degradation rates (and this for Leafs used in Phoenix).

I believe several automakers are showing that BEV are on the cusp of practicality for widespread passenger car use. Tesla has already made the case for luxury car markets, and while Tesla price points are still high for mass market, the pace of reduction is good. As much as I cannot stand Elon Musk, his company has been setting the price / profit curve well ahead of what all prognosticators said possible. The HD truck makers are similarly showing plausibility in regional haul / hub and spoke use.

Oddly enough, MD and HD truck are somewhat better applications than pickup trucks. The main challenge with a pickup (or perhaps SUV too) model is that the edge cases are so far from the base case. Start with a car, like a Chevy Bolt. This is a car that is overbuilt for its 90% use case of running one person to work and back daily. But the edge case of a Bolt loaded with 3-4 people and driving over to grandma's for Thanksgiving is not so far away that the full battery capacity stops making economic sense.

But now take a pickup and the 90% base case (carrying one person to work and back) is really far from the edge case (hauling a boat to the lake, or an RV to a distant campground). Enough battery capacity for the edge case winds up being enough for 1000+ miles of driving in the base case, and the vehicle becomes uneconomical.

HD trucks don't have this problem because the base case is the edge case for most - Fully loaded for about as far as a driver can go in the 11 hour driving limit.

"that never happened" is interesting because I know several folks who have had to replace their Prius batteries. There's even youtube videos instructing how to do it on the cheap.

Now show me a full size, MD, HD, or industrial application where lithium batteries are proven. The GVW information that Tesla withheld when they revealed the Semi concept spoke volumes. Gaining any dramatic increase in range means sacrificing oodles of payload capacity and adding more battery packs. They may have engineered the range to find a sweet spot for short haulers, but that's a far cry from establishing BEV's as proven in these applications. I would be especially interested to see the range drops during the winter temps.

 

[JeffreyG]

"that never happened" is interesting because I know several folks who have had to replace their Prius batteries. There's even youtube videos instructing how to do it on the cheap.

I'm not saying no Prius battery ever failed, I'm saying the doom that "they're all going to wear out in seven years" never happened. Sure, some folks may have had a problem, but if we take the benchmark of a "proven" design I'd rather a Prius battery pack than a GM 3.1 liter V6 intake manifold gasket. Now there is a design that was "proven" to be a disaster. You can find YouTube videos of how to replace your 3.1L V6 intake manifold gasket, provided coolant in oil did not take out the engine first.

They may have engineered the range to find a sweet spot for short haulers, but that's a far cry from establishing BEV's as proven in these applications. I would be especially interested to see the range drops during the winter temps.

With the exception of team-driven vehicles, a semi is not as tough a range situation as you might think. The key is that the operator is limited to 11 hours, and has to take a 30 minute break before the end of the first 8 hours of operation. So drive 6 hours, rapid charge for 30 minutes, drive another 4-5 hours. I really only need a 100% SOC range of ~350 miles and an 80% SOC range capability of ~ 300 miles. The key is the installed infrastructure for the rapid charge at your basic Flying-J. Without that, you need perhaps 500 mile range, which isn't really feasible at the moment. This is why nobody is jumping straight into long distance line-haul applications.

The operating cost advantage of the BEV will drive freight company interest, and adaptation will drive the installed infrastructure. The EPA once told us that they were against SCR because nobody would be able to get DEF, and so nobody would refill it. Now there is DEF at every island at every truck stop. Rapid charging is way harder than that, but if the fleets want it enough it will come. Operating margins in freight are so low, you just cannot afford to ignore whatever proves out to be the cheapest.

I'm not sure winter will affect range all that much. I'm a lot more worried about keeping battery temperatures within the range where they can provide power or accept a charge if the truck is parked away from a charging station. This is why another market, vocational applications, will be very slow to adapt. You are not going to see a BEV logging truck anytime soon.