I don’t understand the “this is new and unproven” bit of the equation. The Prius was introduced in 1997. 1997! 20 years isn’t “proven” enough? How long do people need to accept “new” inventions?
I think a lot of people assume the Prius is an expensive car to keep on the road, that it’s going to blow it’s engine or need new batteries far sooner. To the point that many people assume these extra costs exceed any gas savings, and people just drive Prii in order to feel superior. Everyone seems to assume the battery still costs 5k to replace (ok, it can if you let yourself get screwed at the dealer), that the engine is just one start/stop cycle from throwing a rod, and so on.
Well, 2017 hybrid Fusion has a range of 660 miles, while the best Tesla range is somewhere around half that. (315 IIRC.) So that’s still a pretty big performance gap in that one area.
I have to admit, though, for the driving I do personally, 315 miles would be plenty.
Point taken. For larger states like Texas, maybe the residents need some kind of series hybrid so they can have that kind of range on tap. Right now, the Prius is a great car for Texas - except for that fact that most Texans prefer trucks.
Though…checking.
Houston to Dallas is 241 miles. San Antonio to Dallas is 292 miles. Still within Model 3 LR range, easy.
often enough to basically run at standard idle speed.
what you propose (if it was even workable) would be a shuddering mess.
that’s a 'hit and miss" governor. those stationary engines run at very low RPM and have a massive flywheel to smooth out power fluctuations.
No way. Just because a car is listed as 315 miles in range doesn’t mean you can drive 292. With an electric car, you need to leave a serious margin for emergencies. You get to the charging station, and it’s out of order. You get in a traffic jam. It’s hot, so you need to run the AC and battery cooler. That sort of thing. I also wouldn’t count on the battery being fully charged and in spec.
If I had an electric car with a 300 mile range, I’d be having range anxiety as soon as I hit 200. Likewise, my car has an 80km range after the low fuel warning comes on. So technically, I could drive to work and back a couple of times with my low fuel light on - but I never do. And running out of gas on the side of the road just means a cab bill for 5 gallons of gas. If your electric car dies on the side of the road, you are trailering it home or to the nearest charging station.
I hear there are some towing companies now that have trucks that can so a quick fast charge to get you a few miles down the road, but I wouldn’t count on that.
Fair enough. Though this risk should diminish quite a bit as more chargers pop up. You’re right, though, 292 is too far, you would risk damaging the battery.
You also have to consider the conditions. For example, batteries in electric cars need to be operated in a fairly narrow temperature range. So if you are in a cold climate, you have to run the battery warmer. And in a hot climate, a cooler.
Also, any accessories you use will cut into range. So if you are running the A/C or the heater, that will diminish your range. To a lesser extent, so will the seat heaters, the stereo, etc.
Battery damage shouldn’t be an issue, as the vehicle’s electronics shouldn’t allow you to discharge the battery that far, and the advertised range ahould already factor that in.
But still… In the worst case scenario your electric car can have as little as half of the advertised range, and that doesn’t account for traffic jams and detours and the like.
310 miles of range is seriously good, and it makes the car usable for a lot of people. But even Tesla had to install large numbers of fast charge stations along popular routes before people were willing to drive their electic cars a long way from home.
This isn’t quite true. Teslas by default only charge to 80% capacity because being charged higher than that does damage the battery. As well as discharging below 20%. It costs maybe a cycle every time you do that - meaning the battery lifespan loses 300 miles or so. Under great conditions, the Tesla LR battery could do 250-450k miles, so this loss isn’t much, but it is there.
(about 1000-1500 cycles on LCA, depending on depth of discharge, before the battery is considered unserviceable)
We just purchased a 2018 Jeep Grand Cherokee that had this feature. Thought I would hate it, but it is really unobtrusive. You feel a slight shudder when the endings restarts, but after a few times you forget about it. I also think that it can be adjusted as to the time stopped until the engine shuts off or even turned off. If it saves had, I really don’t see the problem.
I thought the car electronics would prevent you from discharging the battery to the point of damage.
any competently designed battery manager for lithium cells will do everything it can to prevent damage to the cells.
Damage is a relative term. You get 1000 cycles from 20 to 100 percent, vs 2000 to 3000 cycling between 30 to 70 percent. Roughly. The exact cell construction and temperatures will have an effect on this.
So it’s “easier” on the batteries if you electronically limit your Tesla to 70 percent charge and don’t drive it below 30 percent very often.
Prius takes this a step further and only cycles in a very narrow range that is least damaging to the battery.
It looks like the resistance to auto stop/start comes down to these two beliefs:
Starting the engine, even when hot, increases wear, more than having it stopped for brief periods decreases wear.
Increased complication>>>decreased reliability.
And a third reason. If you need greater complexity for more fuel efficiency, many people consider that a bad tradeoff.
I’ve heard it argued that you should drive a 1 ton pickup truck around to do errands like you’d do in a station wagon.
Why? Because the drivetrain components, in an empty truck, are barely being stressed compared to what they would experience in a loaded truck. Ergo, they’ll last forever.
Never mind that the truck burned through 30 - 50 thousand dollars in gasoline over it’s 225,000 mile long life.
I think that everyone has missed the real reason for wear in the bearings during an engine start. When the engine is in use the bearings are under a regime called hydrodynamic lubrication. This means that the shaft and the bearing are not actually in contact and a thin film of oil is maintained between the two surfaces. A picture speaks a thousand words:
The wear is orders of magnitude lower and significantly quieter. When the engine stops the film is not maintained and the two surfaces grind upon start up, causing most of the wear.
As a consumer you need not be worried. The engine is still designed for the same life so now low friction coatings are applied to the bearing surfaces to minimise initial wear. Good oil helps too. Service intervals in Britain have changed from 1year/20,000 miles to 1year/12,500 miles which I attribute to this kind of thing.
A simple question to ask yourself is: Have you ever heard of a properly maintained car engine being scrapped because of a worn bearing?
No. I have heard of Prius engine failures. A few things that lead to failure :
a. Head gaskets can blow, some at 195,000 miles, others at 295,000. A probability curve.
b. A few unlucky folks have actually had internal coolant leaks get so bad that the engine gets destroyed by hydraulic hammering. A couple photos on the forums, where (it’s almost always well over 200,000 miles) there’s actually a piece of the engine block missing. What happens is that if *enough *coolant leaks, it will create an in-compressible slug of water that if a moving part of the engine hits, the shock wave gets transferred to the engine casing and it can break.
c. It uses a special EGR system that has several components. This doesn’t cause engine failure, but it can get clogged to the point that the engine won’t run smoothly. Part of the trick of the Prius is it has some way to heat it’s own coolant using the exhaust gas. This lets it heat very quickly so it gets the coolant to operating temperature in a very brief period of runtime.
Anyways, the ironic - ok, maybe not ironic - thing is that the actual engine failing on a Prius is probably the second most common cause of drivetrain failure. The battery does usually wear out sooner than the engine, but is easier to replace. The EV components don’t fail often at all.