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Hybrid Plug-In Electric Car - vs - Total Electric Car

Only in Nevada can you drive that fast and not get a speeding ticket.
EDIT: I reread you earlier post to try and figure out where the 90 mph came from. Perhaps you mean 2500-3000 RPM which might be an efficient engine speed. Isn't that what the Prius and the REX BMW I3 do? The engine just powers a generator and propulsion is from the three phase electric motor which is more efficient at various RPMs and has a fairly flat torque curve. In both those cars the batteries are what supply the varying current to change the speed of the car.

Essentially that is the way fuel cell cars are configured. The fuel cell is more efficient at a constant output and does not modulate easily so a fuel cell call propulsion system is a battery and electric motor and the fuel cell provides or a fixed amount of power. For acceleration the battery is drawn down to provide the power the motor needs and the fuel cell recharges the battery.
 
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It wouldn't get 120 mpg. Gasoline hybrids get better MPG by using a downsized Atkinson cycle engine that virtually eliminates pumping losses. Diesels don't suffer from pumping losses in the first place, so they don't get this benefit.
1 gallon of Diesel = 38kw/h The Turbo charged Diesel engines get about a 60% efficiency.

38 kwh/h * 0.6 = 23kw/h * 4-5 miles / kwh = 92-114 miles. Yeah you are right my 120 was of - still pretty darn good.

While the Atkison Gasoline Cycle gives you only 38% and Gasoline only contains 33 kw/h per gallon
so that's 33kw/h * 0.38 * 4-5 miles / kwh = 50-62mpg I mean good, but not Diesel good.

Further you can feed a Diesel engine all sorts of crap, including waste vegetable oil.

That is the concept driving most of the freight on trains around the country. We can thank VW for Dieselgate for ruining that segment.
Yep Diesel Serial Drivetrains are powering most of the worlds industry.
VW reacted to market forces and overburdening regulation and choose the dark path.

Just a quick look earlier, both new and used BMW i3 were expensive.
it's a Rear wheel drive, Carbon Fiber Monocoque, electric car from a Premium manufacturer, with 8 year, 80-100k mile warranty. What do you expect? It's not low end budget car. Pre-Covid the i3 used to one of the most affordable used EVs out there. But now people realized the value they are getting from those cars and prices have exploded. No maintenance, no gas, no rust, very little cost per mile, high quality. I could sell my i3 today for almost double the amount I bought in 2020. Which is insane for a used car which is not an antique.
 
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It can for highway driving, with $3.60 per gallon gas at 40 mpg and greater than about $0.21 per kWh utility electric charge.
My calculation is that the gas car above would cost $0.09 per mile and an EV getting 3 miles per kWh would cost $.07 per mile. I do not expect gas to be at $3.60 where I live anytime soon and my cost per kWh while on the road will also be higher. The real savings, as you mention comes from around the town driving at less than 40mph. That is coupled with the fact that most of my charging while at home comes from my solar. I figure over my lifetime my solar will cost $0.05 per kWh.
 
I have a Ford Fusion Energi plug-in hybrid. It's a great car and I love it. It feels like a luxury car. But the battery part of it only gets around 20 miles of range. It's a very small battery compared to full blown EV. But having the hybrid engine gives me the flexibility to run on gas when the battery is drained. A full tank of gas (14 gallons) on this car gets an estimated 600 miles (according to EPA estimates).
 
Isn't that what the Prius and the REX BMW I3 do? The engine just powers a generator and propulsion is from the three phase electric motor which is more efficient at various RPMs and has a fairly flat torque curve. In both those cars the batteries are what supply the varying current to change the speed of the car.
Prius gas engine is always connected to the wheels via a planetary gearset (called an eCVT). The battery isn't really involved in steady-state cruising, mostly it provides acceleration power. Most hybrids and PHEVs use some variation of this approach.

i3 REx is a series hybrid, as you say. The engine has no mechanical connection to the wheels, it only powers a generator. The battery still isn't really involved except in accel and when climbing grades. Series hybrid is less efficient and adds cost. But it's mechanically very simple and handles low speeds, hill starts, etc. without kludges like clutches and torque converters.

Volt mostly used eCVT, but added some clutches (and a second planetary, lol) so it could operate as a series hybrid at low speeds and do other fun tricks. Honda Clarity PHEV also runs as a series hybrid at low speeds, but got rid of all the Volt's planetary gears and all but one clutch. It's a series hybrid below 35 mph (IIRC). Above that the engine connects directly and RPM is slaved to vehicle speed.

1 gallon of Diesel = 38kw/h The Turbo charged Diesel engines get about a 60% efficiency.
Automotive turbo diesels peak at ~45% thermal efficiency. There are R&D projects trying to hit 50% in large truck engines by using secondary cycles (picture a mini steam engine driven by exhaust heat).

38 kwh/h * 0.6 = 23kw/h * 4-5 miles / kwh = 92-114 miles. Yeah you are right my 120 was of - still pretty darn good.
At 45% and 4.5 mile/kWh your math gives 77 mpg. But 4.5 mile/kWh on the highway is unrealistic for all but very small cars. The best mid-size EVs do about 4 mile/kWh and they don't suffer the aerodynamic drag of providing cooling air to a combustion engine. And that 45% efficiency is at the engine block, it doesn't include gear losses and accessory loads. That's why you don't see diesels getting 70 mpg on real highways.

While the Atkison Gasoline Cycle gives you only 38%
Toyota achieves 41% and BYD claims 43%.

and Gasoline only contains 33 kw/h per gallon
Diesel has more kWhs per gallon than gasoline because it has more kgs per gallon. That's also why it costs more. There is no free lunch, though. The original barrel of oil only has so many kgs. Diesel and gas miles/kg and $/kg are basically the same. If you figured out a way to compress gasoline to double density the Camry Hybrid would get >100 mpg. But each gallon would cost twice as much, so it's a false economy (still useful, though, as a smaller gas tank would free up cargo space).

Further you can feed a Diesel engine all sorts of crap, including waste vegetable oil.
You can't run 2 billion cars on WVO. And lots of gas engines can run on ethanol.

Yep Diesel Serial Drivetrains are powering most of the worlds industry.
That's about starting torque, not efficiency.
 
Prius gas engine is always connected to the wheels via a planetary gearset (called an eCVT)
Thanks for that, I was misinformed. At least I was partially correct about the Volt and I think we agree it was complicated. I had assumed the last 18 months on a lease as I awaited my Tesla order and was glad I never owned one.
The Volt did have recall while I leased it because if you did not push the button to turn it off when you parked in the garage it could start in the middle of the night to charge the battery and possibly fill your garage with CO.
 
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There are R&D projects trying to hit 50% in large truck engines by using secondary cycles (picture a mini steam engine driven by exhaust heat).
VW Claims 71%
I know their claims are not to be trusted, But BMW is similar realms, with the heat recovery system you are mentioning.
Currently, I own a Volvo V70 Diesel 2.5L - Station Wagon which hits 46 mpg at normal speeds.

The car gets 23mpg @ 120mph
That's real life German Autobahn, with a big car build 20 years ago, not some R&D.

The newer Volvo D2 diesel are getting around 60 mpg.

That's about starting torque, not efficiency.
Torque from the engine doesn't matter that much in a Serial Hybrid with a Battery - it matters in a application without a battery - correct.
Diesel has more kWhs per gallon than gasoline because it has more kgs per gallon.
Many parts of the world 84% of all countries Diesel is cheaper then Gasoline because it's less Energy intensive to refine, e.g. it's cheaper to produce.
They just found a way to rip you off in the US.

You can't run 2 billion cars on WVO.
most cars will run on electric for 98% of their drives and only for those once twice a year long distances drives will activate the generator

But 4.5 mile/kWh on the highway is unrealistic for all but very small cars. The best mid-size EVs do about 4 mile/kWh and they don't suffer the aerodynamic drag of providing cooling air to a combustion engine. And that 45% efficiency is at the engine block, it doesn't include gear losses and accessory loads.
I'm averaging 4.6 mpg with my i3 - it has 4 real seats and I can load a washing machine and 2m - 8ft lumber - the car is small on the outside - but has amazing space utilization on the inside - since it's a true EV design.

There are no accessories on combustion engine developed as a generator.

Amazing that Gasoline engines are getting better. Really good thanks for sharing the links. Was about time.
 
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it's a Rear wheel drive, Carbon Fiber Monocoque, electric car from a Premium manufacturer, with 8 year, 80-100k mile warranty. What do you expect? It's not low end budget car. Pre-Covid the i3 used to one of the most affordable used EVs out there. But now people realized the value they are getting from those cars and prices have exploded. No maintenance, no gas, no rust, very little cost per mile, high quality. I could sell my i3 today for almost double the amount I bought in 2020. Which is insane for a used car which is not an antique.

Rear wheel drive not great for where I live.

”No maintenance“ So this is not the hybrid as previously mentioned.

”No rust” What is their secret, stainless steel?
 
my take is that we should hit a point where BEVs are significantly cheaper to build than PHEVs, but it is hard to know when we hit that point on battery pricing.
I took an Audi training several years ago that said they are already spending more to build the wiring in the car, than the engine and transmission combined. So it is not 'just' a battery thing.

But someone else pointed out that a catalytic converter can cost as much to build as an engine, so ditching the ICE drivetrain is not 'just' the engine/transmission either.

Why aren't we making EVs with a small engine. Size it to make enough power to drive the car at 90 mph and make it run at a single speed load point, making it as efficient as possible at that single point.
Well, the i3 REX is somewhat like that, but Mazda for a while was developing EVs with a rotary engine as a range extender which i thought was very exciting. Rotaries can't cheaply be made to be efficient or clean across the huge speed and load range required to be the 'prime mover', but they can be optimized to be VERY good at a fixed load and speed, plus they have incredible power density and low NVH compared to piston engines. Alas, they never did release one as a production vehicle. Still kinda sad about it.

I would love to have a PHEV with a Diesel Engine - the Audi/VW TDI 1.2L - 74 HP - gets amazing fuel economy at 2000 rpm - the VW Golf with that engine gets 78 MPG. Combine that with a electric drive - we would be looking at 120+ MPG
It already exists, VW XL1


volkswagen-xl1-plug-in-diesel-hybrid_100419663_h.jpg
 
China high speed trains network is an economic disaster only surpassed by its real estate fiasco.
I have travelled in China until COVID. I have seen many of those projects and wondered when the bubble would burst. The high speed trains work well and from my perspective were reasonably priced. What was interesting was that most Chinese are already used to electric propulsion since most scooters are electric. Even the farmers bringing their produce to farmers market drive small three wheel pickups that are electric.
 
Rear wheel drive not great for where I live.

”No maintenance“ So this is not the hybrid as previously mentioned.

”No rust” What is their secret, stainless steel?
Rear wheel drive is fine when you got all weight down low. The i3 has 50:50 distribution. Many rear wheel drive vehicles you remember probably don't have much weight in the back - and those are terrible - I used have 3 series and my heavy American Pickup - that thing had no traction whatsoever.

you can buy the i3 as a BEV or as PHEV. I've opted for the version without the engine. Because I don't like Dealers- a EV I can maintain with a phone app - while for an ICE engine/car I need a whole workshop.

Everything on the i3 is either plastic, carbon or aluminum. Nothing to rust, rot etc. You can scratch the paint everywhere, nothing will happen.
 
VW never said that. Your blogger misinterpreted numbers from a Wired magazine article and did some bad math. The production XL1 was a PHEV. The claimed 260 MPGE (take special note of the "E") was based on 2/3rds of the test cycle coming from battery power.

VW did say XL1 could get 120 MPG on diesel alone, but I don't know at what speed. 120 mpg at 8.4 hp road load would be 33% efficiency. But I think that 8.4 hp is also bunk. That's the power of the original 1 cylinder engine in the prototype. The XL1 was a much different car, with a two cylinder engine and side-by-side seating instead of tandem. It probably required 11-12 hp to sustain 60 mph, putting engine efficiency near 45%.

Many parts of the world 84% of all countries Diesel is cheaper then Gasoline because it's less Energy intensive to refine, e.g. it's cheaper to produce.
They just found a way to rip you off in the US.
You're right, I shouldn't have used price to support my argument. Gas vs. diesel price depends mostly on taxes plus local supply/demand. It will settle at the roughly same price per kg in a stable, unrestricted market, but good luck finding one of those. Most countries (e.g. China, Japan, Europe, etc.) tax "consumer" gasoline more heavily than "industrial" diesel. The US is the opposite, though the difference here is only pennies per gallon.
 
Gas vs. diesel price depends mostly on taxes plus local supply/demand.
Supply and Demand should always determine the price. Doesn't change that Diesel is cheaper to produce and less energy intensive. Easier to store, doesn't evaporate, not as flammable, far superior in long-term stability. We had used diesel which was in tanks for 10 years - no problem.

Diesel is the better fuel IMHO, gas is fine when you use it right away, like in regular car- but a for a Serial Hybrid, which I got in mind which runs only a handful of times a year - Diesel is the best choice.
Should be also much easier to build a emission compliant Diesel which only runs at one speed instead of a range.
 
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90 mph is so the ICE has sufficient power to not only continue moving the car but to also be putting energy back into the batteries, like grades or towing. And I would make it so the ICE is designed to run a single speed & load point with no throttling, raising it's efficiency.

The Chevy Volt 1st gen proved this was a terrible idea.

Why not go with what's been used for 25 years? The CVT. With a CVT, you get to pick the optimal rpm for any given power setting.

It's kinda like you took at look at the most successful HEV system on the planet for the last 25 years and said... "No... the opposite of that."
 
I wouldn't call any car with a CVT successful. And the idea was to make the engine as efficient as possible. If I'm running a single speed and load I can optimize cam timing and intake and exhaust tuning improving efficiency.
 
With a CVT, you get to pick the optimal rpm for any given power setting.

It's kinda like you took at look at the most successful HEV system on the planet for the last 25 years
Which 25 year old hybrid has a CVT? The Prius has planetary gears.

CVT can't take much torque, just friction physics stuff. Sure perfect in a small light car, but not above. I drove a Subaru Justy - that thing was fun with CVT.

If I'm running a single speed and load I can optimize cam timing and intake and exhaust tuning improving efficiency.
No we are talking, you can do a lot of things with a single speed engine. Including overlapping valve timing so that the exhaust stays inside the chamber. So you can get rid of of external EGR systems. You can fine tune a turbo charger to the ideal wheel size.

Without a external EGR you can also run Direct injection without messing up your intake valves with exhaust.
 
I'm going to stick up for the Volt a bit here, both in terms of concept and implementation. I've had two of them, a first generation 2012 and a second generation 2017. My daughter now has the 2012. I got the 2017 because I wanted the longer electric range and adaptive cruise control.

Where the Volt excels above most other PHEV concepts is that it is a full fledged electric car when it has battery power and a full fledged ICE car when running on gas. By this I mean that the electric mode does not have limited speed or power compared to the engine, like the Prius does. And in ICE mode, it runs like a normal car (except you notice it doesn't have the clunkiness of shifting through gears) and has normal power and range, unlike the i3 with a range extender. With the battery full and the gas tank full, it can go over 400 miles. I like the implementation using two motors (not three) and an engine with a planetary gear set. When it needs to engage one of the clutches, it is able to speed match the friction disc before engaging, so the transmission should see minimal wear.

In terms of my use of the vehicle, I drive mostly in a city with some short interstate drives. In town, I rarely ever use gasoline. Last year I put a total of 16 gallons of gas in it and this year I put 3 gallons in it in February and 7 gallons in June. Now I'm down to half a tank. I have had the 2017 for three years now. I changed the oil when I first got it and according to the oil life meter still have 38% of my oil life left. Other than that, I have added washer fluid and fixed a flat tire. The 2012 Volt had a coolant reservoir level sensor go bad, which prevented charging of the battery. That was a pain to diagnose and fix, but GM makes the software and module programming downloads available in a way that it was cost effective to do it myself.

So the original question was PHEV or all Electric. I will probably never buy another car with an engine. However, at present I need the ability to do a 250 mile trip at the drop of a hat, even when it is 0°F and windy, in the event that my aging parents need help, and I can't afford an EV with that capability. So the Volt gives me 90% of the benefits of an EV with all of the flexibility of an ICE car.

As for the defenders of diesel engines, while you can convince me they still have a place in long haul trucking in rural places, I think they are too damaging to health to run in a city. Having a diesel bus or truck pass me when I'm riding my bicycle is noxious and choking. The pm 2.5 particles are an issue that leads to respiratory and other health problems.

Back in the 90's, I looked into what it would take to convert a car to electric and get 12 miles of range so that I could drive to work. It was possible but super expensive for a limited use vehicle. Then in 2015, I was able to buy a used car with an electric drive train that could go 38 miles on a charge, and still had an engine, for less than the cost of doing a conversion in the 90's. So I am confident that by the time I need to get my next car, there will be an all battery electric option that will meet my needs.
 
I am on my third EV since May 2011. I would skip the hybrid.
Do you have range anxiety? I started driving EVs in 2012 and I don't have range anxiety. The onlyiT people I know who have range anxiety are people who don't drive EVs.
EDIT: @hankcurt doe make a good practical case for a hybrid.
 
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The initial short range was a struggle at times early on. And was rather limiting fairly often. Yes arriving home with less than 5 miles can give a person pause. Especially in the early days with virtually no charging infrastructure. Absolutely no issue these days with 250 mile range and charging stations plentiful.

Only real anxiety was driving the LEAF back to work from the dealer at initial purchase back in May 2011. Was a 60 mile drive and still had 12 mile drive to get home and charge. Made it without issue and has not been an issue since.

And yes once I ran out close to home and could not make it up a short hill.... literally coasted into the local shopping center and had to push maybe 12' into the parking stall with a charge cord. Just don't turn it off until it is parked ready to charge.

Charging at home, priceless. Charging at work as an employee benefit, simply wonderful.
 
Volt excels above most other PHEV concepts
the Volt is good car - nice aerodynamic. If Chevy would have added a bit more battery capacity it would have been a winner.

As for the defenders of diesel engines, while you can convince me they still have a place in long haul trucking in rural places, I think they are too damaging to health to run in a city. Having a diesel bus or truck pass me when I'm riding my bicycle is noxious and choking. The pm 2.5 particles are an issue that leads to respiratory and other health problems.
fully agree, while I defend the Diesel long range - it shouldn't be running in cities. There should be trains and bikes for people and EV for delivery traffic.

Volvo is producing a full line up of Electric City trucks and you can get nice electric busses from various manufacturers.

Serial Diesel Hybrid as for long range as as stop gap until we got charging lanes on highways.
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Which 25 year old hybrid has a CVT? The Prius has planetary gears.
Prius has a CVT. It continuously varies the gear ratio between the engine and drive axle.

It's not a belt-and-pulley CVT, of course. But a CVT based on planetary gears is still a CVT. Toyota calls it an eCVT.
 
It's not a belt-and-pulley CVT, of course. But a CVT based on planetary gears is still a CVT. Toyota calls it an eCVT.
thanks, I learned something new today. I used to have Prius :)

They shouldn't call it the same acronym. Belt driven CVTs have really a bad rap.
 
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