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The onething I find that lacks from their webpage and the thread is clear data on calculations or basic understanding of what you get. I am new to Karma, so the first thing that hits me is they assume you understand the modes of the car how it works what you get and then here are some added benefits Powersource can provide. I find this lacking, it doesn't compel me to buy and I think the product sounds great!

I'd like to see some scenarios that cover factors and explain how the TOM works in different modes of car: Sport, Hill, Stealth (the youtube video doesn't explain this very well).

I feel it needs some charts and milage graph examples showing you what you could expect and different speeds, time, and idle (worst case or conservative numbers). I need to see data and this brings me to question:

If I drive 1000 miles nonstop, assume on the Interstate, AVG 70 MPG what would I expect my EV miles to be vs gas miles driven? Example 650 gas miles to 350 EV miles?
 

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What did they tell you, in response to your question?
I'm sure, you first tried to ask them, before blaming here?

I'm always getting sufficient answers, although I'm with you, it could be explained a little more in detail on their site.

Stefan
 

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Discussion Starter · #3 ·
What did they tell you, in response to your question?
I'm sure, you first tried to ask them, before blaming here?

I'm always getting sufficient answers, although I'm with you, it could be explained a little more in detail on their site.

Stefan
I've sent Julian an email about another topic, never got a response so I opened the thread to get an answer from actual users or the company themselves.

I am not blaming anyone, in fact I said it's good. I am just asking for clarification and offering my feedback and the frustration over lack of information. Are we at the point where feedback is considered blaming? I don't think any of that is blaming. It's intent is to help further the product to sell. I would like to buy one, but I need better data and understanding. Simple feedback given and a hope to get a response.
 

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...

I'd like to see some scenarios that cover factors and explain how the TOM works in different modes of car: Sport, Hill, Stealth (the youtube video doesn't explain this very well).

...

If I drive 1000 miles nonstop, assume on the Interstate, AVG 70 MPG what would I expect my EV miles to be vs gas miles driven? Example 650 gas miles to 350 EV miles?
I will let @PowerSource handle the TOM modes, but in the Karma's basic modes:

  1. Stealth: In Stealth mode, the Karma uses the HV battey alone for power until the battery gets down to 15% charge. At that point, the ICE (gas engine) starts up and maintains the HV battery at 15% by replacing whatever power is used to move the car.

    In your hypothetical, the first 40-45 mile of your 1000 mile trip will be on stored power, and, assuming you don't charge the car along the way, the rest on power generated by burning gas. In my experience, the fuel economy in this mode is around 23 - 27 MPG. If you do charge the car during your trip, in this mode the stored charge will be used first. This is the Karma's default mode.


  2. Sport: Sport is slightly more complicated. If you switch to sport when the battery is more than half full (i.e., 50 - 26 indicated miles), the HV battery will be used as the primary source of power and the gas engine will be used to provide additional power if you call for it. The number of miles you get in this mode depends on how aggressively you drive. When the battery drops below half (25 miles or less indicated), the gas engine and generator will replace the power used to move the car and maintain the HV batteries charge state. For example, if you switch to sport mode when there are 20 indicated miles of EV range, you will notice that the indicated range will stay at or near 20 miles as you drive (it will go up or down by a couple of miles in response to traffic conditions, but will return to 20 eventually). The point here is that you can reserve up to 25 miles of EV range, for city driving, for example. To turn off the gas engine, you can switch back to Stealth mode and use the charge remaining in the battery.

    In your hypothetical 1000 mile trip, if you start out in Sport mode, you will be using gas the entire time, either to supplement the EV range or to maintain it. Any portion of the trip that you drive in Stealth mode with the battery indicating more than 0 miles range will be driven on stored power and the gas engine will come back on after the battery reaches 0 indicated miles remaining.

    In my experience, you can expect around the same MPG as Stealth mode in Sport mode. The only difference is where you use stored power vs. power generated on board.

As I understand it, the TOM units sold by @PowerSource provide additional modes beyond stealth and sport, and I will leave that explanation to them.

TL;DR: YMMV
 

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I hope they do - I'd love to hear more, in the simple non technical way you have begun. Looking forward to more.
 

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There was already a thread discussing exactly the real world effective mileage of before and after TOM install. on 500+ mile trips effective mileage before TOM was in mid-high 20's (no ability to plug in and recharge after first 50 mile charge used) after TOM installed, on 600+ mile trip my effective mileage increased to 34 mpg.

Pretty straightforward and simple.
 

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Discussion Starter · #7 ·
There was already a thread discussing exactly the real world effective mileage of before and after TOM install. on 500+ mile trips effective mileage before TOM was in mid-high 20's (no ability to plug in and recharge after first 50 mile charge used) after TOM installed, on 600+ mile trip my effective mileage increased to 34 mpg.

Pretty straightforward and simple.
I did read it if that was the one from the owner discussing the trip computer and his thought that is didn't take into count the TOM recharge miles.

I did get a response from Julian @ Powersource and he answered my question and gave me some variants, but great info and ER mode builds up the charge while driving, so overall it sounds promising if you travel a lot, want to keep using the battery, and are environmental conscious.
 

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I'm sorry, but I really have a hard time buying that TOM will (can) change mileage at all. If the engine is the same & the generator is the same, then the power output of the two is the same and the mileage (from gasoline) will be "the same". It doesn't matter when you use the EV & Gas miles, the power available from a single tank to be put into the battery is the same.

If you used a TOM unit to build back the up the Stealth miles, it's not "buying" you any mileage. It's just storing it for later use but burning the gas now. The gas engine generates power & replaces the battery charge at around 10 KwH per gallon burned. That's around 26 driving miles worth of power. Whether you keep the Stealth miles close to 50 or let it get down to 0 it's still the same power generated and sent into the battery per gallon of gas burned.

You'll get 50(ish) miles from charging up from an outlet. To keep apples to apples we should ignore those when computing gas mileage. So, if you start a long (500 mile) drive with a fully charged battery & a full tank and come home with 0 Stealth miles, you subtract those (say 40-45 actual) Plug-In miles from your total distance driven and then divide the remainder by the gallons of gas you used when you filled it back up (obviously for at least 2 times). I'm gonna bet that'll be a number right around 26 mpg no matter what TOM/Stock Modes you used along the way. You'll have burned gas for 460 of those 500 miles, and you'll have used 17-18 gallons. If you come home with more than 0 stealth miles, it means you burned more gas than you needed to on the trip. So, if you come home with 20 Stealth miles showing (and having never plugged in), then you got 30 (ok, maybe really 25) non-gas miles and the rest was generated from gasoline. So, you'll have used gas for 475 miles and burned 18-19 gallons. But, the gas generated miles per gallon will always be around 26.

Unless there's something I am seriously not getting (which is certainly possible - but I haven't heard it, yet) ... What I do know tells me that the Karma'a electric motors consume ~10 KwH (42%) of a battery charge to go 26 miles. The ICE/Genset generates around ~10 KwH per gallon of gas. The engine is the engine & the Genset is the Genset, and I cannot see how TOM could possibly increase the amount of power generated PER GALLON. It only determines how hard & how often the engine runs -- certainly giving you more freedom of when power is generated and stored, but not increasing the rate of power generated per gallon. And not giving you more range per tank/charge. The mileage generated from gasoline will always be around 26 mpg when you factor out the Plug-In miles. The things that will make mileage vary will be passenger/cargo weight & the speed driven (i.e drag). That'll change it by +/- 1 MPG. But, I don't see anyway that the gas mileage will (could) jump to 34. That'd mean you could go up to 390 miles on a single tank/charge.

I'm just not able to buy that without a lot more concrete data or a solid explanation of what I don't understand. Somebody educate me, please.
 

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I'm sorry, but I really have a hard time buying that TOM will (can) change mileage at all. If the engine is the same & the generator is the same, then the power output of the two is the same and the mileage (from gasoline) will be "the same". It doesn't matter when you use the EV & Gas miles, the power available from a single tank to be put into the battery is the same.
Pretty hard to argue with empirical Miles Traveled/Fuel Burned data provided in this post. Admittedly, it is a very small sample size of 1, but the methodology seems pretty sound. A few posts later in the same thread, @powersouce explained that TOM uses a different algorithm for running the ICE, but I don't think that the answer was definitive, one way or another.
 

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TOM keeps the battery at 90+%, where Karma easily climbs hills.
Without TOM, if I'm down to 20%, Karma has a hard time, climbing the same hill and the ICE is crying to ****, never allowing 200km/h

In my theory (!!!), TOM drives the ICE at a range, where upping the battery is more economic.

If the long trip involves hills, I wouldn't complain.
 

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I'm sorry, but I really have a hard time buying that TOM will (can) change mileage at all. If the engine is the same & the generator is the same, then the power output of the two is the same and the mileage (from gasoline) will be "the same". It doesn't matter when you use the EV & Gas miles, the power available from a single tank to be put into the battery is the same.
The 2012 cars bleed off miles without banking them into the battery. For example, drain your battery to 40 net electric miles, put the car in Drive and press the brake pedal and accelerator simultaneously for 5 minutes. Do the battery miles go up even though your engine is running? Where is this energy going? The energy flow screen will show negative power consumption or a net of 0 kw being generated- even though the ICE is running. There is definitely a load on the engine (generator) so where is the energy going?

If you used a TOM unit to build back the up the Stealth miles, it's not "buying" you any mileage. It's just storing it for later use but burning the gas now. The gas engine generates power & replaces the battery charge at around 10 KwH per gallon burned. That's around 26 driving miles worth of power. Whether you keep the Stealth miles close to 50 or let it get down to 0 it's still the same power generated and sent into the battery per gallon of gas burned.
The 2012 cars bleed miles while driving, for example when you fill your tank with gasoline and the ICE runs, using the theory that the "power output of the two is the same" the vehicle should be generating electric miles after a fill up if the load characteristics allow for it (i.e. no or minimal traction load). This begs the question where does the excess energy go from the generator when the engine runs? Apparently not back into the battery.

For the energy calculations, these calculations are at a standstill with the vehicle generating energy while idling (roughly the same RPM as force starting the engine with the procedure I described above). We don't have a full thermal efficiency map of the LNF, but I think everyone can agree that the Karma bleeds miles (likely wasted in heat) instead of banking them when the ICE is running to get to the magic 26/27 SPORT range sustain number.

You'll get 50(ish) miles from charging up from an outlet. To keep apples to apples we should ignore those when computing gas mileage. So, if you start a long (500 mile) drive with a fully charged battery & a full tank and come home with 0 Stealth miles, you subtract those (say 40-45 actual) Plug-In miles from your total distance driven and then divide the remainder by the gallons of gas you used when you filled it back up (obviously for at least 2 times). I'm gonna bet that'll be a number right around 26 mpg no matter what TOM/Stock Modes you used along the way. You'll have burned gas for 460 of those 500 miles, and you'll have used 17-18 gallons. If you come home with more than 0 stealth miles, it means you burned more gas than you needed to on the trip. So, if you come home with 20 Stealth miles showing (and having never plugged in), then you got 30 (ok, maybe really 25) non-gas miles and the rest was generated from gasoline. So, you'll have used gas for 475 miles and burned 18-19 gallons. But, the gas generated miles per gallon will always be around 26.
There is wasted energy in 2012 "STOCK" mode see above experiment while even when a load is introduced the vehicle stock behavior is to bleed these miles rather than bank them to get to the magic range sustain number. This surely cannot be more efficient than banking these "wasted" miles?

Unless there's something I am seriously not getting (which is certainly possible - but I haven't heard it, yet) ... What I do know tells me that the Karma'a electric motors consume ~10 KwH (42%) of a battery charge to go 26 miles.
The nominal usable battery capacity is around 17kWh not 20.1 (i.e. 20.1 x.15=~17kwh usable) This would in essence mean energy usage of around 294wh/mi which I don't think is possible in a Karma. It is probably closer to 400+ wh/mi (i.e. 42 actual miles @ 17kWh usable which is pretty congruent with real world use).

The ICE/Genset generates around ~10 KwH per gallon of gas. The engine is the engine & the Genset is the Genset, and I cannot see how TOM could possibly increase the amount of power generated PER GALLON. It only determines how hard & how often the engine runs -- certainly giving you more freedom of when power is generated and stored, but not increasing the rate of power generated per gallon. And not giving you more range per tank/charge. The mileage generated from gasoline will always be around 26 mpg when you factor out the Plug-In miles. The things that will make mileage vary will be passenger/cargo weight & the speed driven (i.e drag). That'll change it by +/- 1 MPG. But, I don't see anyway that the gas mileage will (could) jump to 34. That'd mean you could go up to 390 miles on a single tank/charge.
The stock Karma bleeds miles (try the force engine test above and see if you can generate any miles) and uses a different strategy (mainly to mimic the ICE of a normal vehicle). There are unaccounted stock losses, that are not taken into consideration.


I'm just not able to buy that without a lot more concrete data or a solid explanation of what I don't understand. Somebody educate me, please.
It all depends on drive cycle if you do a cross country trip at 45 miles the ICE will work a lot less harder than at 0 miles because the nominal bus voltage is higher- which is inherently more efficient than at 15% SOC- among other factors.
 

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Let's simplify the discussion for me, since you are the expert @PowerSource. Are you saying that with a TOM unit, it is possible for a person could do significantly better than 300 miles total range on a full tank & charge?

My normal "long trip" mode is to engage Sport Mode when my car gets down to 27 Stealth miles and maintain 27 through the trip until I'm back close to home. And, then, I use my remaining Plug In miles. And, I get around 26-27 MPG for the gas miles. Meaning I get around a 300 mile range for the car on one tank/charge. Maybe only 280. Can TOM modes allow that to be bested?
 

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JCMorrill, seriously, you do NOT have to buy the TOM module from PowerSouce, why do you keep bothering them with the same questions over and over, they already told you a year ago that they won't sell this module to you
 

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JCMorrill, seriously, you do NOT have to buy the TOM module from PowerSouce, why do you keep bothering them with the same questions over and over, they already told you a year ago that they won't sell this module to you
Because I actually care about accurate information being exchanged, here. PERIOD. That's the point of these forums.

When the TOM module first came out, I was interested and kept initially asking if/how it would improve the mileage. And, (my recollection was that) @PowerSource (rudely) eventually made it clear to me that it would not. If you're reading those old posts, maybe you'd notice that.

The attempted insult to me was that I was the kind of Karma owner who was more focused on the green aspects of the car and less on the performance, so "I wouldn't be the right kind of customer for a TOM unit."

So, now - when people (not PowerSource!) are asserting the opposite -- that the mileage & range improves with TOM. That seems like false information being disseminated to me. And, I care about that. So, I question it. And, if my understanding is wrong, I am anxious to correct it.

Why my asking direct questions on a forum designed for exchanging such information is considered impolite escapes me.
 

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I love the work PowerSource is doing, especially retrofitting the infotainment center... i'm more interested in this since I decided to keep my car a couple more years. The only reason I bought the Fisker is because it was the only green and luxurious car available.

Thank you JCMorrill helping us make sense of all this technical stuff. Please don't stop. Looks like we all endear our Karmas. I love SpeedyZX9R's passion, but please keep it friendly.
 

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Let's simplify the discussion for me, since you are the expert @PowerSource. Are you saying that with a TOM unit, it is possible for a person could do significantly better than 300 miles total range on a full tank & charge?

My normal "long trip" mode is to engage Sport Mode when my car gets down to 27 Stealth miles and maintain 27 through the trip until I'm back close to home. And, then, I use my remaining Plug In miles. And, I get around 26-27 MPG for the gas miles. Meaning I get around a 300 mile range for the car on one tank/charge. Maybe only 280. Can TOM modes allow that to be bested?
See my last paragraph

PowerSource said:
It all depends on drive cycle if you do a cross country trip at 45 miles the ICE will work a lot less harder than at 0 miles because the nominal bus voltage is higher- which is inherently more efficient than at 15% SOC- among other factors.
The Ecotec motors (and generally every ICE out there) are usually most efficient within a certain RPM band. Keeping the RPM's synchronous with power demand is inherently more efficient than revving up and down to mimic an ICE vehicle with a transmission. Banking all available miles rather than bleeding them off is also more efficient.

Arch fisker's real world data seems to indicate the TOM unit does make the vehicle more efficient with his particular drive cycle.

So your answer is yes, the overall vehicle range can increase, utilizing our algorithm. By how much depends on your drive cycle. I hope this ends this discussion once and for all.
 

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That does make sense. Thank you! At certain RPM's the ICE is running more efficiently, and you're saying that the engine gets to run more at those RPM's when keeping the battery closer to 90% (45 Stealth) than 15% (0 Stealth miles). It really could take one to 34 MPG, though? That seems huge. Can you post more samples as you get them, Arch? As this would certainly make a TOM more attractive to those who love the green aspects of the car and not just to the high performance lovers.
 

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Planning on it. Each long trip I take I track it as a separate event to provide PowerSource with additional real world data.

Remember to those that are skeptical, the Karma was originally planned to have charge on the fly. And if you know anything about a turbo motor, it develops max torque when at full boost, which requires a nice steady RPM or sustained acceleration. The logic that the car does not need 250 hp to cruise at 70 just to sustain the battery means that some of that uncaptured potential energy is lost vs dumped into the battery. I'm a layperson but the logic seems sound to me and I am getting a real world opportunity to test the hypothesis and it comes out correct. Kudo's to the PowerSource team and Boooo to the those that simply want to pick on others and do nothing themselves that compares.
 
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