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I'd readily admit I'm not the sharpest knife in the drawer when it comes to numbers, it I think some of you are. :nerd:
I'm trying to figure out operating costs for the EV power of the Niro PHEV. Here in Seattle the electric rate is 11 cents / Kilowatt hour. How would I determine the cost of juice to drive 26 in BEV mode? Thanks
 

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I'd readily admit I'm not the sharpest knife in the drawer when it comes to numbers, it I think some of you are. :nerd:
I'm trying to figure out operating costs for the EV power of the Niro PHEV. Here in Seattle the electric rate is 11 cents / Kilowatt hour. How would I determine the cost of juice to drive 26 in BEV mode? Thanks
the epa sticker claims 32Kwhrs per 100miles.

26miles x 32kwhr / 100miles x 0.11 cents/kwhr = $0.92
 

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I use not to trust that much the stickers ;)

I would say :
- 80% of battery used for EV (26 miles)
- battery is 8.9 kWh
- charger efficiency is ~80% (20% lost in conversion)

So the end result is:
((8.9 * 0.8) / 0.8) = 8.9 kWh required
8.9 * .11 = $0.97 (which is very close to what charlesH found)

Christophe.
 

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I assume the epa spec takes charging losses into account.
I don't think that EPA takes charger efficiency in account as it is function of charger used (some may be very efficient, some other like home-charger less efficient).
This is why I used a common rule of 80% knowing that in some case scenario it can be worse, in which case you will pay more kWh for the same amount in your car.

Christophe.
 

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I don't think that EPA takes charger efficiency in account as it is function of charger used (some may be very efficient, some other like home-charger less efficient).
This is why I used a common rule of 80% knowing that in some case scenario it can be worse, in which case you will pay more kWh for the same amount in your car.

Christophe.
The niro "charger" ( converts 120/240 AC to battery level 400v? DC) is in the car. The cord that plugs into the wall plug is just a WIRE (plus signals). It's not converting anything. 100% efficient.

Don't you think it is reasonable to assume gallons/mile and Kwhrs/mile are handled the same way. Measure gas at the pump or Kwhrs at the plug and then measure resulting miles.

I've measured at the plug Kwhrs for a full recharge after ~26 miles ev driving. It's ~ 8.3 Kwhrs. Consistent with 8.9Kwhrs total and the epa spec 100miles/32Kwhrs x 8.3Kwhrs = 26 miles.
 

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I've measured at the plug Kwhrs for a full recharge after ~26 miles ev driving. It's ~ 8.3 Kwhrs. Consistent with 8.9Kwhrs total and the epa spec 100miles/32Kwhrs x 8.3Kwhrs = 26 miles.
your calculation is consistent if you consider that the Niro uses 100% of the battery, but each time I plugged it with '0' miles EV remaining, I'm still at ~20% battery, this is why I consider that full charge is only 80% of 8.9kWh and not the full battery.

And I'm pretty sure that between your home power meter and your battery in the car, there are some lost energy in conversion (conversion is never 100% efficient). And all discussion I read and video on energy consumption on EV car, the average number used for that conversion loss is ~20%.

This video explains the loss of EV at 9:33 using the efficiency of Tesla charger at 90% which is high.


Christophe.
 

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your calculation is consistent if you consider that the Niro uses 100% of the battery, but each time I plugged it with '0' miles EV remaining, I'm still at ~20% battery, this is why I consider that full charge is only 80% of 8.9kWh and not the full battery.

And I'm pretty sure that between your home power meter and your battery in the car, there are some lost energy in conversion (conversion is never 100% efficient). And all discussion I read and video on energy consumption on EV car, the average number used for that conversion loss is ~20%.

This video explains the loss of EV at 9:33 using the efficiency of Tesla charger at 90% which is high.
https://www.youtube.com/watch?v=f7MzFfuNOtY


Christophe.
Sure, the in car charger is not 100% efficient. But the charger inefficiency is included in the epa 32kwhr /100miles spec, just like the ICE inefficiency is in the epa mpg spec. You don't need to adjust the EPA spec for either powertrain losses .

Do you adjust the epa MPG spec for the ICE 40% efficiency ?
 

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If you're driving a PHEV, then with a full charge, you have an approximate 26 mile range. When you've depleted that range to 0 miles, you're likely to observe a 20% state of charge reported on the instrument console. The car drops out of full-time EV mode around 20% state of charge (SOC). The car depends on the traction battery to start the ICE, so driving the battery to 0% SOC would be a disaster, because you wouldn't be able to start the ICE (and it would also be bad for battery "health" to let it deplete to that extent). Essentially, the PHEV begins to behave like an HEV when the PHEV battery hits 20% SOC. Or you can invite the car to begin behaving like an HEV sooner than that by toggling the EV button while there's still more than 20% SOC in the battery.



When you are looking at the EPA numbers, I believe you are looking at the KWh that the charger consumed to increase the charge from 0 miles EV range to 26 miles EV range, and SOC wasn't a consideration. I don't recall for certain, but I think the EPA numbers measured the KWh consumed by the charging device, not the KWh absorbed by the battery.
 

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If you're driving a PHEV, then with a full charge, you have an approximate 26 mile range. When you've depleted that range to 0 miles, you're likely to observe a 20% state of charge reported on the instrument console. The car drops out of full-time EV mode around 20% state of charge (SOC). The car depends on the traction battery to start the ICE, so driving the battery to 0% SOC would be a disaster, because you wouldn't be able to start the ICE (and it would also be bad for battery "health" to let it deplete to that extent). Essentially, the PHEV begins to behave like an HEV when the PHEV battery hits 20% SOC. Or you can invite the car to begin behaving like an HEV sooner than that by toggling the EV button while there's still more than 20% SOC in the battery.



When you are looking at the EPA numbers, I believe you are looking at the KWh that the charger consumed to increase the charge from 0 miles EV range to 26 miles EV range, and SOC wasn't a consideration. I don't recall for certain, but I think the EPA numbers measured the KWh consumed by the charging device, not the KWh absorbed by the battery.
I think this is correct.

FWIW,
Yesterday I drove per Google maps 29 miles in ev mode and then fully recharged with 7.98 Kwhr measured at the plug.

That's 29/7.98 = 3.63 miles / Kwhr

EPA spec is 100/32 = 3.125 miles /Kwhr

So "your mileage may vary " applies to ev mode too.
 

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Sure, the in car charger is not 100% efficient. But the charger inefficiency is included in the epa 32kwhr /100miles spec, just like the ICE inefficiency is in the epa mpg spec. You don't need to adjust the EPA spec for either powertrain losses .

Do you adjust the epa MPG spec for the ICE 40% efficiency ?

You are talking about totally different things. The Electric Motor inside the NIRO is not 100% efficient.



The EPA is talking about the amount of power inside the car translated to the amount of distance it can travel. It does not cover any efficiencies or losses in getting the electricity into the car. Just like it doesn't account for the accuracy of the gasoline pump when you fill your car, or the amount of drip spillage when pumping or if you went with Chevron vs Costco gasoline.
 

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You are talking about totally different things. The Electric Motor inside the NIRO is not 100% efficient.



The EPA is talking about the amount of power inside the car translated to the amount of distance it can travel. It does not cover any efficiencies or losses in getting the electricity into the car. Just like it doesn't account for the accuracy of the gasoline pump when you fill your car, or the amount of drip spillage when pumping or if you went with Chevron vs Costco gasoline.
Well we will have to just disagree. I believe epa measures gas gallons in or kwhrs in and then how far you can drive.

I measure gas and kwhrs in and then miles driven and my results agree with the epa spec.

Your theory implies I should be measuring worse than the epa spec. However, I measure better than the epa spec.
 

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Well we will have to just disagree. I believe epa measures gas gallons in or kwhrs in and then how far you can drive.

I measure gas and kwhrs in and then miles driven and my results agree with the epa spec.

Your theory implies I should be measuring worse than the epa spec. However, I measure better than the epa spec.

Perhaps you need to read what you said.


Your theory is that the EPA calculates in the ineffeicancies of a car charger ?? becuase they use kw/h in what they post. Then threw out there in your defense something about how since the ICE is only 40% efficiant so as that is included in their spec for gas milage, that the charger efficiancy would be too.


I just pointed out the the efficiancy of the ICE is irrelivent just as the efficiancy of the electric motor inside the NIRO is.


As well, I pointed out that the EPA uses a measure fuel (be it electricity or gasoline) inside the car and not how that fuel gets put there. That is the users problem. I pointed out that gas stations don't always give you exactly what you think you paid for an that difference is just inherrant error. The battery inside the car is charged to a certain level and then the EPA tests. It doesn't start with an empy battery an plug the car in to a wall socket and charge for so many KW/H, just like they don't take a car to a gas station and pump in so many gallons of fuel on the pump dial and assume it is right.
 

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Perhaps you need to read what you said.

Your theory is that the EPA calculates in the ineffeicancies of a car charger ?? becuase they use kw/h in what they post. Then threw out there in your defense something about how since the ICE is only 40% efficiant so as that is included in their spec for gas milage, that the charger efficiancy would be too.


I just pointed out the the efficiancy of the ICE is irrelivent just as the efficiancy of the electric motor inside the NIRO is.


As well, I pointed out that the EPA uses a measure fuel (be it electricity or gasoline) inside the car and not how that fuel gets put there. That is the users problem. I pointed out that gas stations don't always give you exactly what you think you paid for an that difference is just inherrant error. The battery inside the car is charged to a certain level and then the EPA tests. It doesn't start with an empy battery an plug the car in to a wall socket and charge for so many KW/H, just like they don't take a car to a gas station and pump in so many gallons of fuel on the pump dial and assume it is right.
NOTE: THE NIRO L1/L2 CHARGER IS ON BOARD, in the car, just like the electric motor and battery. Do you realize this????? [L3 chargers ARE external.]

Your theory implies I should be measuring worse miles / kwhr than the epa spec does it not? Because I should be adjusting for the on-board charger inefficiency which according to your theory the epa doesn't account for?

I measure BETTER than the epa spec.

If the experimental data doesn't support your theory time to adjust your theory.

Are you an engineer or scientist? Just asking.
 

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NOTE: THE NIRO L1/L2 CHARGER IS ON BOARD, in the car, just like the electric motor and battery. Do you realize this????? [L3 chargers ARE external.]

Your theory implies I should be measuring worse miles / kwhr than the epa spec does it not? Because I should be adjusting for the on-board charger inefficiency which according to your theory the epa doesn't account for?

I measure BETTER than the epa spec.

If the experimental data doesn't support your theory time to adjust your theory.

Are you an engineer or scientist? Just asking.
For clarity I will add.

All L1/L2 plugs/cords are not voltage converters thus they are 100% efficient . They do not convert ac to dc for battery charging. The 120/240 v in the wall plug goes directly into the car plug and connects to the on board IN THE CAR ac to dc converter/charger which is ~90% efficient.
 

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Watts/mile has NOTHING to do with charger efficiently. It is measuring how far you can go on battery power regardless of how the battery was recharged.
 

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Watts/mile has NOTHING to do with charger efficiently. It is measuring how far you can go on battery power regardless of how the battery was recharged.
One measures mpg by filling the tank, measuring miles driven, and then measuring gallons needed to refill the tank. Then a little math gives you mpg.

Calculating miles per kwhr is done the same way. Fully charge the car, measure miles driven, measure kwhr needed to fully recharge the car. Math gives you miles per Kwhr.

Any other method makes no sense to the consumer.
 

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One measures mpg by filling the tank, measuring miles driven, and then measuring gallons needed to refill the tank. Then a little math gives you mpg.

Calculating miles per kwhr is done the same way. Fully charge the car, measure miles driven, measure kwhr needed to fully recharge the car. Math gives you miles per Kwhr.

Any other method makes no sense to the consumer.
how should a consumer measure mpg?

How should a ev/phev owner measure mpkwhr?
 

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how should a consumer measure mpg?

How should a ev/phev owner measure mpkwhr?

For a PHEV owner driving exclusively on plug-in charge, something like this measures the electricity consumed by charging: https://www.amazon.com/P3-P4400-Electricity-Usage-Monitor/dp/B00009MDBU/ref=asc_df_B00009MDBU


Your odometer measures miles (if you trust it, otherwise, look for a highway that marks off measured miles).


And then the math for "mpkwhr" is just the miles divided by the kwh reported by the meter.


For mpg, the usual drill is to fill the tank, reset the odometer, drive a good distance, refill the tank again (preferably at the same pump and in the same way), and then calculate miles driven divided by gallons added (on the second visit).


Regarding "the same way" to fill the tank: a lot of people seem to like to try to squeeze in a bit more after the pump first kicks off to indicate a full tank. When you do that, you introduce inconsistencies in your technique (which will affect your mpg calculation), and you also expose yourself to some potential problems. It's best to stop when the pump kicks off the first time. If you overfill the tank, and then it has a chance to warm up and expand before you've consumed that additional amount of fuel, you're probably either over pressurizing your fuel system or else pumping raw fuel (rather than just vapor) into the evaporation emissions control system. In some locales, due to vapor recovery technology on the gas pump, you might also wind up with a big spill on the ground if you try to squeeze in a bit more after the pump first kicks off. I learned that lesson the hard way, one of the first times that I tried to "squeeze in a bit more" from a gas pump in California. Never again.
 
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