Speculation Alert - possible Harvester Engine Choices

[theek]

This is exactly what I would expect.

This might be a user-selectable mode - you could drive in a pure EV mode for most around-town trips, but if you know you're going on a road trip or off-road, you select the appropriate mode, the Harvester kicks on, and off you go.

Aka "tow mode"

 

[speedrye]

This is it. This is how I was thinking it should be handled. Just didn't come to my mind as well as you put it.

My question is, what happens if you're on EV only mode for like a really extended period of time. Since you plug in every night?

Will there be a gas maintenance mode so that it doesn't get all gunked up?

I'd definitely be running non-ethanol gas in mine, likely with STA-BIL in there when I'm not anticipating longer trips. Being a sealed system unlike mowers, blowers, etc, gas will stay fresher longer with or without ethanol, but I wouldn't chance it.

 

[Derek]

This is it. This is how I was thinking it should be handled. Just didn't come to my mind as well as you put it.

My question is, what happens if you're on EV only mode for like a really extended period of time. Since you plug in every night?

Will there be a gas maintenance mode so that it doesn't get all gunked up?

The i3 did that. It would kick on and run for 10 minutes once a month or so while doing normal driving around with nothing required from the driver (it had some kind of timer).

 

[dearbulls]

And then watch your roads fall apart.

Granted, EV annual registration taxes are regressive taxes that only wealthy people can afford, but they still have to pay for road maintenance for state roads somehow, and EVs are heavier than comparable ICE vehicles today so they have a larger impact on the roads.

Seems to me they should implement a point-of-charge tax, and/or tax home charger usage through utilities tied to registration. But that's an argument for a different place and time.

This is bull crap. with all the HD trucks and Semis, why the road do not fall apart, but only with EV? Wife's ID.4 is similar weight to a new aluminium body F150, it's also 1000 lbs lighter than my steel body F150. And I only pay $20 each year for the F150, no special taxes. The only heavy weight thing are those large electric SUV and pickups like CT, Hummer, Silverado EVs with huge batteries, which has near or exceed 5 digits in lbs on weight.

On the other hand, unless you are driving a superduty, you will never use 200-300 worth of "EXTRA" tax from fuel miles. The tax for road maintenance you were talking about differs by state. For my state of GA, it's 0.33 per gallon. For $300 extra tax, you'll need to use 909 gallons of fuel each year. And for my hybrid Ford Maverick which gets 42 MPG on average, That's equal to 38,182 miles per year. How many normal people drive this much each year per vehicle? Even for my 3 vehicles combined, I won't drive this much. It's why I'm saying it is stupid.

And this is why I, as an EV owner, against the trend of having more large EV with large batteries.

 

[dearbulls]

You don't need math.

Range extender will increase sales among those with Range Anxiety.

Well, on this behalf then yes. Even if it doesn't provide the full 500 miles of full performance, if it can get you that far at reduced performance, it would still be better than a pure BEV with only 250-350 miles range.

 

[dearbulls]

All we have right now is what they've told us.

150 EV only range for the Harvester, and then 500 miles of range while using the range extender. What they haven't told us, is how it will do that.

TLDR:

IMO, Scouts will have an efficiency between that of a Hummer EV, and a Rivian R1 vehicle, around 2 miles per KW.

IMO the Harvester will most likely have a ~75kw useable battery, and a generator capable of producing ~35-80kw/hr, if they want it to keep up with the load on the freeway.

Lots of words:

At one extreme it could be that the Harvester generator will be small, and run the entire time (including while at 100% charge), because it cannot keep up with the expected electrical load to operate the vehicle by itself. Meaning, they're intending the vehicle to be charged/fueled up at the end of that 500 miles. This scenario is most similar to the BMW i3 REX.

At the other extreme we have the scenario where the Harvester engine is big enough to keep up with expected electrical demands, and they intend you to fuel up like a PHEV at the end of that 500 miles of range, and continue on with gasoline until you find a place you want to charge again.

We can also ballpark guess at efficiency. The Hummer EV has an efficiency of 1.6 miles per KW. The Rivian R1 series is between ~2.1-2.4 miles per KW depending on configuration. I'm guessing the Scouts will be less efficient than the Rivians (because aerodynamics), but more than the Hummer. Which means I believe we'll get something like ~1.8-2 miles per KW out of them.

With the range they gave us, and the efficiency guess, we can guess the size of the battery. If we assume 2 miles per KW of efficiency for easy math, the 150 mile range is then a ~75kw useable battery for the Harvester models. And to go 500 miles, you'd need ~250KW of electrical energy. So 250kw -75kw of battery = 175kw of the total energy has to come from the gasoline generator.

If that 2 miles per KW efficiency was based on 70mph, then in an hour we've used ~35kw. I personally don't think we'll see a generator smaller than that (the much smaller i3 REX used a 25kw generator, and the Chevy Volt used a 50kw one, I really doubt we'd see something smaller, but you never know).

I understand your logic, just your use of UNIT drives me crazy.

Battery capacity is kWh, and it is KW x Hour, which is equal to what you said "~75kw". It's for a 75kW output engine run at peak performance and continue running for 1 hour, how much power it produces (75kWh).

There's no such thing of "kW/hr", because kW is power output at that very moment.
So where you said KW/hr is actually just KW.

 

[dearbulls]

Modern car fuel system are incredibly well sealed now, so there should be less evaporation and water absorption.

I do hope they can put that Cayman Boxer engine in there.

 

[dearbulls]

That was not my experience in our 2015 i3. I could hold 70 on a fairly level freeway.

Another real world 'limp mode' experience and observations

I realize much has been written here about limp mode — here’s our real world experience. We have 1300 miles on our i3 REX- all around our town over the past couple of months — Love the car - fun to drive and all that. I have a level 2 charger at home and rarely charge away from it. Decided to...

www.mybmwi3.com

Check it out here on the i3 forum.

What's your SOC when you cruising at 70? we are talking about when the battery SOC is low and it's only relying on the gas generator. Then it went into limp mode

 

[Logan]

I understand your logic, just your use of UNIT drives me crazy.

Battery capacity is kWh, and it is KW x Hour, which is equal to what you said "~75kw". It's for a 75kW output engine run at peak performance and continue running for 1 hour, how much power it produces (75kWh).

There's no such thing of "kW/hr", because kW is power output at that very moment.

Turns out, I'm not used to conversing in electrical terminology like this.

But, it does appear that my head is on straight, and my maths "math", which is some relief.

Eventually I'll get it straight .

 

[CarTechGeek]

Another real world 'limp mode' experience and observations

I realize much has been written here about limp mode — here’s our real world experience. We have 1300 miles on our i3 REX- all around our town over the past couple of months — Love the car - fun to drive and all that. I have a level 2 charger at home and rarely charge away from it. Decided to...

www.mybmwi3.com

Check it out here on the i3 forum.

What's your SOC when you cruising at 70? we are talking about when the battery SOC is low and it's only relying on the gas generator. Then it went into limp mode

That didn't contradict him. In that link it appears they were doing 75 MPH on level ground, it was when they started climbing that they ran into issues.

At mile 70, Rex turned on and we continued on for 25 miles or so at freeway speed. At mile 90, we started a gradual upslope. speed dropped from 75 to 64 mph. The last mile of freeway is a steep upslope of about 1000’. REX dropped to 28. SCARY!!!

So 75 MPH on level ground, 64 MPH at gradual climb, and then significant drop to 28 MPH on a steep climb...

This is kind of what is expected for the i3 Rex. It has no problem maintaining highway speed on flat terrain, as the poster said. It's the climbs that will cause issues.

 

[UberBar]

Already called the crated 70’s beetle engines

Oscar Mike Golf - that is funny!

 

[UberBar]

My vote:

Compact, efficient, high power density, and demonstrated to work.

Our Technology – INNengine

innengine.com

I was just thinking how cool a turbine engine would be then remembered the rotary is pretty close equivalent lt and very compact!

Things that make you go hummmmm.......

 

[R1TVT]

Can you imagine if Scout announced the availability of the Harvester - an option that would provide owners a "fully-limped range of up 500 miles"... I'm guessing that would not be super appealing for a truck or SUV buyer.

The BMW i3 can retain its limp mode features and functions.

The thing that everyone is forgetting is the sheer weight, shape and size of the Scout. Its a block on wheels. It's not a BMW i3. The implementation of a range extended version of this truck with an engine that fits into a compact space and allows the truck to retain its frunk will absolutely need to be different. Time will tell though.

 

[MountainDad]

This is bull crap. with all the HD trucks and Semis, why the road do not fall apart, but only with EV?

Because they pay higher taxes on diesel fuel. This is why diesel is more expensive than premium in some states.

 

[R1TVT]

...Except my last 2500 (gas, NOT diesel) weighed about the same as my current EV truck.

 

[MountainDad]

...Except my last 2500 (gas, NOT diesel) weighed about the same as my current EV truck.

Right, and you're paying taxes on your fuel for it too. You get lower mileage than you would with a diesel, so you're buying more fuel at a lower tax rate. It all works out.

 

[R1TVT]

Correct, not just diesel, and wherever you drive, the taxes may vary - in some cases wildly. I had no idea IL had such a high gas tax, for example, while AK is dirt cheap.

 

[MountainDad]

I was just thinking how cool a turbine engine would be then remembered the rotary is pretty close equivalent lt and very compact!

Things that make you go hummmmm.......

Turbines and rotary engines are actually nothing alike. Turbines are far more powerful for a similar sized occupied engine volume, but they have efficiency issues that require special air handling to mitigate. They'd work great under a high-pressure weather system in the middle of an Alaskan winter in Anchorage, with cold, dense air...but in the middle of a Phoenix summer heat wave, they would be terrible.

Rotaries could maybe be tuned to be good generators but they suffer from a lot of blow-by which reduces their efficiency and creates emissions problems.

 

[MountainDad]

Correct, not just diesel, and wherever you drive, the taxes may vary - in some cases wildly. I had no idea IL had such a high gas tax, for example, while AK is dirt cheap.

...which is why there has to be some solution to replace these taxes as EVs gain market share over time, which they will, regardless of the administration in power. The wisest way would be some point-of-charge tax, but for those with home chargers like me who never charge on public infra, there would need to be some other method that doesn't penalize people with a massive registration bill. In Colorado, registration is based on the value of the vehicle, indexed to a constant rate of depreciation. My Polestar cost over $1300 the first year, and that only included a $25 EV sticker. If you then added on some equivalent road tax to replace fuel taxes -

 

[R1TVT]

Its an interesting debate, because you are trying to incentivize good behavior then potentially burden the sale with additional taxes. EV drivers may have heavier vehicles in some cases, but they may also be doing more good than harm compared to ICE when looking through a much broader lens. How you attribute that benefit across a variety of different federal & state agencies may be more difficult and harder to quantify. I hear you on taxes. I live in taxachussets and we incur a similar heavy excise tax on everything (cars, trucks, trailers, boats, etc.)

In Massachusetts, residents pay a $25 excise tax for every $1,000 of the value of every car they own each year (fortunately they depreciate the vehicle YoY), so new cars ARE expensive. Half the states in the US do not have a vehicle excise tax.