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Discussion Starter #1 (Edited by Moderator)
Moderator Note: The OP was misinformed in the post below. The Nissan is not like the BMW i3 EV. Instead it's like the Chevy Malibu, e.g., a very small battery ICE hybrid with no plugin capability.
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Nissan is taking a step backwards while GM is taking the step forward. It is going to copy the concept of the iBMW 3 Rex, limping home when the battery rans out. The Chevy Volt has still enormous power even when the battery rans out. Now GM is going the next logical step, the Chevy Bolt EV, a pure electric with no range anxiety at an affordable price. Nissan has gone the other way!

http://mobile.reuters.com/article/idUSKBN15G3VM
 

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Nissan is taking a step backwards while GM is taking the step forward. It is going to copy the concept of the iBMW 3 Rex, limping home when the battery rans out. The Chevy Volt has still enormous power even when the battery rans out. Now GM is going the next logical step, the Chevy Bolt EV, a pure electric with no range anxiety at an affordable price. Nissan has gone the other way!

http://mobile.reuters.com/article/idUSKBN15G3VM
It isn't taking a step backwards, it is a great idea. No, brilliant idea. If you can sell a series hybrid like the Note e-Power for about $16,000, and sell say 5 times as many of those as you do the Nissan Leaf. Suddenly all your electric powertrain components get cheaper because they are shared with your "gas" cars and you are producing 6 times as many as with just the EV. Your power inverters and your electric motors all get cheaper. The manufacturer is able to sell the car cheaper as it has a small battery, no complicated automatic or shifting transmission, and no on board charger (chargers are expensive). To be fair, the components aren't identical to the Leaf, but an idea like this does allow sharing and production cost decreases.

The engine is 80 hp so it will not have the issues that the i3 has. This is as much power as the engine in the Gen 1 Volt.
http://www.goo-net-exchange.com/catalog/NISSAN__NOTE/10106993/

To me, doubling the efficiency of a compact car without increasing the price is pretty good.
 

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Discussion Starter #4
It isn't taking a step backwards, it is a great idea. No, brilliant idea. If you can sell a series hybrid like the Note e-Power for about $16,000, and sell say 5 times as many of those as you do the Nissan Leaf. Suddenly all your electric powertrain components get cheaper because they are shared with your "gas" cars and you are producing 6 times as many as with just the EV. Your power inverters and your electric motors all get cheaper. The manufacturer is able to sell the car cheaper as it has a small battery and no on board charger (chargers are expensive). To be fair, the components aren't identical to the Leaf, but an idea like this does allow sharing and production cost decreases.

The engine is 80 hp so it will not have the issues that the i3 has. This is as much power as the engine in the Gen 1 Volt.
http://www.goo-net-exchange.com/catalog/NISSAN__NOTE/10106993/

To me, doubling the efficiency of a compact car without increasing the price is pretty good.
There's a point there. It is inescapable fact that Nissan can't come up with anything that can compete with the Chevy Bolt EV for the range and price. The market is headed there at the moment. The demand for Chevy Volt has also been on the increase, while the price decreases, so Nissan must have sensed something in GM's profit margins for the hybrid.
 

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The point is to not compare the Note e-Power in anyway to the Bolt EV and was in development probably at the same time. This is competition of the most entry level car market and costs 1/2 the price of a Bolt EV ($16,000 vs $38,000). The next Nissan Leaf replacement will be competition with the Bolt EV. This car is not targeted towards you or EV buyers, but rather to reduce prices for other EVs and make users more comfortable with an EV.

Nissan is perfectly capable of coming up with competition for the Bolt EV, but they (and every one else) were taking their time not expecting GM to pull off what they did in the time line that they did it.
 

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Nissan is taking a step backwards while GM is taking the step forward. It is going to copy the concept of the iBMW 3 Rex, limping home when the battery rans out. The Chevy Volt has still enormous power even when the battery rans out. Now GM is going the next logical step, the Chevy Bolt EV, a pure electric with no range anxiety at an affordable price. Nissan has gone the other way!

http://mobile.reuters.com/article/idUSKBN15G3VM
No, it's _not_ going the i3 REX route. In fact almost the reverse.

This is a serial __HEV__ with a _small_ battery and a _regular_ engine.

I think that it's a great thing to see because it means that engineering effort is focused on electric motors, batteries, power electronics and ICEs as RExes isntead of ICEV transmissions and ICEs for propulsion.

Simplifies the powertrain and that helps packaging as well as cost.

It's a design that really suits a car that will be driven in the city.
 

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Interesting, a car with an all electric propulsion system but equipped with only a tiny 1.5 KWH battery without a plug. Sort of like a Chevy Malibu Hybrid except the Malibu propulsion system is parallel hybrid where either the electric motor or the ICE, or both deliver power to the wheels. In the Nissan approach the drive motor has to be capable of delivering enough power to cover the entire performance envelop. In the Malibu the two motors are capable of propelling the car to maximum speed, but are not used that way since that would quickly depleat the battery. Instead, the motors are used to assist the ICE when torque demands are high such as launching from a stop or accelerating on to the freeway. This gives the Malibu V6 performance even though it has a smallish 4-cylinder ICE. However most of the time such as steady crusing the Malibu's power comes directly from the ICE (one of the electric motors in the Voltec transmission does use a small amount of power to provide variable gearing for the ICE).

Since both vehicles derive their power from the ICE most of the time, it seems to me a series hybrid approach, such as the Nissan would be less efficient then a parallel hybrid like the Malibu. In one (series) double losses are incurred when ICE mechanical power is converted to electricity which is then reconverted by the traction motor back to mechanical power to power the wheels. The I3 does this and even though it is a small car and its ICE is only 600 CC, the gas mileage is only around 38 MPG while the Malibu gets something around 46 MPG.

The 1st gen Volt was akso mostly series in its operation but it had a plug-in battery large enough to handle the majority of trips driven by an average driver. Unlike the 1st gen Volt, this Nissan hybrid with its tiny battery probably has to be powered from the ICE most of the time. Why do it using a series architecture when a good old fashioned mechanical drivetrain would be more efficient?
 

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You get rid of the complicated (and inefficiency of the) transmission and share costs with your normal electric vehicles. Easier to package too, the engine can be anywhere in the car. This e-Power should get over 80 mpg in Japan, maybe nedc rating or similar (maybe 55-60 mpg EPA)
 

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Interesting, a car with an all electric propulsion system but equipped with only a tiny 1.5 KWH battery without a plug. Sort of like a Chevy Malibu Hybrid except the Malibu propulsion system is parallel hybrid where either the electric motor or the ICE, or both deliver power to the wheels. In the Nissan approach the drive motor has to be capable of delivering enough power to cover the entire performance envelop. In the Malibu the two motors are capable of propelling the car to maximum speed, but are not used that way since that would quickly depleat the battery. Instead, the motors are used to assist the ICE when torque demands are high such as launching from a stop or accelerating on to the freeway. This gives the Malibu V6 performance even though it has a smallish 4-cylinder ICE. However most of the time such as steady crusing the Malibu's power comes directly from the ICE (one of the electric motors in the Voltec transmission does use a small amount of power to provide variable gearing for the ICE).

Since both vehicles derive their power from the ICE most of the time, it seems to me a series hybrid approach, such as the Nissan would be less efficient then a parallel hybrid like the Malibu. In one (series) double losses are incurred when ICE mechanical power is converted to electricity which is then reconverted by the traction motor back to mechanical power to power the wheels. The I3 does this and even though it is a small car and its ICE is only 600 CC, the gas mileage is only around 38 MPG while the Malibu gets something around 46 MPG.

The 1st gen Volt was akso mostly series in its operation but it had a plug-in battery large enough to handle the majority of trips driven by an average driver. Unlike the 1st gen Volt, this Nissan hybrid with its tiny battery probably has to be powered from the ICE most of the time. Why do it using a series architecture when a good old fashioned mechanical drivetrain would be more efficient?
Consider that in the Prius if you're driving below 45mph (and the engine is warmed up) the car will mostly be driven using the electric motors.
The e-Note is a small car that will be expected to be driven at city and suburban speeds.
By serializing the drivetrain they make the car cheaper, simplify the powertrain and simplify packaging. And, in a serial arrangement the car will drive like a BEV when there's enough charge and power available.
 

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You get rid of the complicated (and inefficiency of the) transmission
Adding more energy conversions (mechanical->electrical->mechanical, or worst-case: mechanical->electrical->chemical->electrical->mechanical) is likely to be less efficient than direct engine-to-wheel mechanical powertrains like other conventional hybrids.

Of course, if this car is small and light, it still might get impressive MPG.
 

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Interesting, a car with an all electric propulsion system but equipped with only a tiny 1.5 KWH battery without a plug.
Wait, the Note e-Power has no plug? That is, indeed, a step backwards. Just like the Malibu hybrid based on Voltec, which should also have a plug.
 

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Adding more energy conversions (mechanical->electrical->mechanical, or worst-case: mechanical->electrical->chemical->electrical->mechanical) is likely to be less efficient than direct engine-to-wheel mechanical powertrains like other conventional hybrids.

Of course, if this car is small and light, it still might get impressive MPG.
Isn't this like a train? I think pickup trucks will eventually be like this.
 

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Adding more energy conversions (mechanical->electrical->mechanical, or worst-case: mechanical->electrical->chemical->electrical->mechanical) is likely to be less efficient than direct engine-to-wheel mechanical powertrains like other conventional hybrids.

Of course, if this car is small and light, it still might get impressive MPG.
A series hybid drivetrain will likely do better than ICE in stop-go driving. At high speeds, no. This is why Volt switches to parallel at high speeds to the angst of EV purists. By using series hybid instead of ICE only you can prevent wasteful idling, use regenerative braking, and run engine at ideal RPMs. So even though you have conversion losses, you will likely do better than straight ICE.

I don't understand why people are complaining about this, it is a definite step in the right direction for ICE. It also means common AC and other high voltage components to take alternator and engine belt loads off.
 

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I don't understand why people are complaining about this, it is a definite step in the right direction for ICE. It also means common AC and other high voltage components to take alternator and engine belt loads off.
My complaints were not with the car but with the marketing.

An electric car without a plug that is only sold overseas , is unsettling to me and obviously others in both the EV and hybrid worlds.
It is a step back from a plugin and should not target plug ins.
Whether it's marketing excites average drivers we will see.

The fact is that those of us who want a true EV "hope" that Nissans very novel small, cheap and lightweight generator in a motor series electric drivetrain gets a plug.
But since the car is not plug in and doesn't beat the Prius, us EV heads find it irritating because no plug no sale for many.

My hope is that this novel drivetrain ends up far more efficient than normal series due to the generator being inside the motor.
Also it must be bulletproof reliable which makes Nissan viable (to me at least) and hopefully allows them to release this lightweight drivetrain into all their offerings .

If they can beat Prius motor efficiency over certain speed ranges and gain platform efficiency due to weight savings and be 33% or more less expensive than a Prii I think it's a real win.

Anything that removes normal ICE autotragic cars off the road and makes them more reliable and efficient is a win to me.

Put a DI 2 cycle on it and a plug it would be golden.

But for gods sake offer a plug in version.
 

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Nissan is joining the hybrid market, just as Toyota, Honda, Hyundai, and the three domestics are doing. If the Leaf BEV market is small, then the Note hybrid is the next best thing to save gas and lead buyers into a BEV for their next vehicle. Not every hybrid needs to be a plug-in for battery charging. Ford sells more hybrid Fusions and C-Maxs than the Energi versions, so they have all those markets covered.

The new Chevy Malibu Hybrid will sell well, and allow GM to test that market before creating a larger plug-in sedan.
 

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A series hybid drivetrain will likely do better than ICE in stop-go driving. At high speeds, no. This is why Volt switches to parallel at high speeds to the angst of EV purists. By using series hybid instead of ICE only you can prevent wasteful idling, use regenerative braking, and run engine at ideal RPM. So even though you have conversion losses, you will likely do better than straight ICE.
Idk why you're comparing the serial hybrid to a regular non-hybrid ICE. That's not the question. It's serial vs parallel.

Serial hybrids intuitively seem like they should be very efficient if you can run a small engine at optimal rpm's. That's what I thought circa early 2010. But that benefit is overblown in reality. The Gen 1 Volt's weak 35 mpg_city -- even with premium fuel -- is a great example of this configuration's real-life limitations, as is the fact that no other automakers' conventional hybrids employ a serial configuration. They use a parallel configuration DESPITE its complexity precisely because it's more efficient.

The reason (explicitly stated in the article) for Nissan to choose a serial configuration for this vehicle is cost.
 

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Nissan is taking a step backwards while GM is taking the step forward. It is going to copy the concept of the iBMW 3 Rex, limping home when the battery rans out. The Chevy Volt has still enormous power even when the battery rans out. Now GM is going the next logical step, the Chevy Bolt EV, a pure electric with no range anxiety at an affordable price. Nissan has gone the other way.
The OP should really edit this post to correct or remove this incorrect statement so people aren't misinformed/confused.
 

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Idk why you're comparing the serial hybrid to a regular non-hybrid ICE. That's not the question. It's serial vs parallel.

Serial hybrids intuitively seem like they should be very efficient if you can run a small engine at optimal rpm's. That's what I thought circa early 2010. But that benefit is overblown in reality. The Gen 1 Volt's weak 35 mpg_city -- even with premium fuel -- is a great example of this configuration's real-life limitations, as is the fact that no other automakers' conventional hybrids employ a serial configuration. They use a parallel configuration DESPITE its complexity precisely because it's more efficient.

The reason (explicitly stated in the article) for Nissan to choose a serial configuration for this vehicle is cost.
The 2017 Honda Accord hybrid has a city EPA rating of 49 mpg which is mostly driven using its series hybrid mode. It also has a single fixed ratio parallel mode when driving steadily or with modest acceleration at speeds above 40-45 mph and that gets it an EPA highway rating of 47 mpg.

While a series hybrid is simpler and can skip the expense of a full transmission it has its own cost downsides. It requires 2 motors and inverter circuits that match the power of the gas engine whereas a car like the Hyundai Ioniq hybrid only needs one motor with about half the power of the gas engine but then still needs a separate transmission. A power-split system like a Prius or Malibu hybrid splits the difference by requiring 2 motors (one of them about half the power of the gas engine) but it uses a mechanically simpler transmission.
 

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Serial hybrids intuitively seem like they should be very efficient if you can run a small engine at optimal rpm's. That's what I thought circa early 2010.

They use a parallel configuration DESPITE its complexity precisely because it's more efficient.

The reason (explicitly stated in the article) for Nissan to choose a serial configuration for this vehicle is cost.
Series hybrids can be more efficient than a standard auto transmission.

Historically they could be up to 70% efficient which was better than old Hydromatics

Nissans claim is that they made a more efficient electric cvt.

By having the generator inside the electric motor acting directly on it like a transformer it is possible they have gotten its through efficiency up.

Until hard motor generator efficiency numbers are provided and real world non-Japan cycle fuel numbers come to light I am cautiously optimistic.

On the Japanese cycle the Nissan note hybrid is on par in city numbers VRS Prius and about 10% below on highway but again the Japanese cycle is rather meaningless and the type of car the us gets is usually different than the Japanese version.
 
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