What confuses me about the Acura 350h is that it does not seem to be a PHEV, but up to a certain speed it will operate only from the battery and if you drive slowly and not accelerate too much it will stay on battery only? I guess they didn't bother giving a range spec as it doesn't apply in this case, as it is not truly a PHEV. I don't know what kind of algorithms they are using so I was hoping someone in here can shed some more light on this.
The NX 350h is a Lexus, not an Acura, and it is a regular hybrid. The NX 450h is a PHEV.
When coasting or going downhill at above 40 mph, the engine still must rotate but will do complete cylinder deactivation. The exhaust and intake valves are closed and fuel delivery is shut off. This eliminates pumping losses and overall the drag is pretty low.
The Toyota hybrid architecture has changed over the years but the majority of these are based on some kind of power-split device. This allows the electric motors and engine to run simultaneously with the pairing of motors and planetary gearset acting as a variable-ratio transmission, and it gives these cars the "e-CVT" gearbox marketing name, but crucially these cars do not really have a CVT with all of its associated problems. The hybrid synergy drive is actually a rather clever architecture and it deserves praise for its simplicity and performance (as much as I think hybrids are becoming obsoleted by pure electric vehicles for most users.)
So the ICE is still mechanically coupled to the wheels via the transmission via some gear ratio, so it is actually still rotating the crank shaft and cylinders are pumping but empty (no fuel/spark), or does the ICE get disconnected from the wheels completely (like when the transmission is put into "Neutral" or like when a clutch is pressed down?).
There is also "parallel" and "series" hybrid configurations, where in parallel mode both ICE and electric motor can drive the wheels (coupled to transmission).... i.e. "electric motor assist", whereas in the series mode the ICE is used to primarily produce electricity for the electric motor system and not coupled directly to the drivetrain (essentially it is an EV with a small efficient ICE that runs only to charge the battery when needed). I'm assuming the second type (series) would be more likely to be in the PHEV type of vehicle.
However, many times they seem to be sold to people who do a lot of driving on the highway, and this might be where the 60km/h claim also comes into it. These people would be better with diesel or pure EV, but Toyota doesn't like marketing either.
That depends on the type of hybrid; the only hybrids to consider need to have a true Atkinson cycle engine. Such engines are much more efficient so even on highways, you'll get a much better mileage compared to a conventional ICE based car. Unfortunately there are only a few manufacturers that make such hybrids (typically with a drive train from Toyota).
Just for completeness, there's one category missing, the mild hybrid.
These have thrown away the alternator and starter motor, and replaced them with a motor capable of moving the vehicle and being used as a generator. This is combined with a relatively small lithium chemistry battery - 1 kWh or less.
As for mild hybrids: they are more like an improved stop-start system with a 48 volt electrical system so they can use an electric AC compressor. They hardly count as a hybrid -- while the motor can technically move the car it is a negligible fraction of overall traction power.
However, many times they seem to be sold to people who do a lot of driving on the highway, and this might be where the 60km/h claim also comes into it. These people would be better with diesel or pure EV, but Toyota doesn't like marketing either.No. Diesel is expensive to run & repair (been there, done that) and emits a lot of pollution. An EV takes long to charge (with expensive electricity from fast chargers on top of that). I already ran the numbers and a Toyota hybrid offers the best economy for doing long highway journeys plus having very low emissions.
(as much as I think hybrids are becoming obsoleted by pure electric vehicles for most users.)
However, many times they seem to be sold to people who do a lot of driving on the highway, and this might be where the 60km/h claim also comes into it. These people would be better with diesel or pure EV, but Toyota doesn't like marketing either.No. Diesel is expensive to run & repair (been there, done that) and emits a lot of pollution. An EV takes long to charge (with expensive electricity from fast chargers on top of that). I already ran the numbers and a Toyota hybrid offers the best economy for doing long highway journeys plus having very low emissions.Yes, you have extremely strong and blinkered opinions about what works for you, but dont mention all the constraints/conditions which make that true.
Here in Australia (where diesel and petrol are almost identically taxed, no incentive either way there) a diesel car is cheaper on running costs as the maintainence has been shown to be no higher than petrol engines, either type of engine wears out well past the other drive train parts which are common to both. That's comparing identical models available in both engines, slightly higher upfront cost, lower operating costs. Which applies to hybrids, higher upfront cost for promise of lower operating costs.
One of the auto associations here puts out a broad (but somewhat shallow) analysis:
https://rac.com.au/car-motoring/info/buying-a-car/running-costs
For the typical 15,000km/year and mixed city/highway driving that normal people do, the life-cycle cost of any engine choice petrol/diesel/hybrid ends up lost in the noise. People need to be heavily biased toward/away from long distance highway driving, or much higher/lower km use for any difference to appear.
However, many times they seem to be sold to people who do a lot of driving on the highway, and this might be where the 60km/h claim also comes into it. These people would be better with diesel or pure EV, but Toyota doesn't like marketing either.No. Diesel is expensive to run & repair (been there, done that) and emits a lot of pollution. An EV takes long to charge (with expensive electricity from fast chargers on top of that). I already ran the numbers and a Toyota hybrid offers the best economy for doing long highway journeys plus having very low emissions.Yes, you have extremely strong and blinkered opinions about what works for you, but dont mention all the constraints/conditions which make that true.
Here in Australia (where diesel and petrol are almost identically taxed, no incentive either way there) a diesel car is cheaper on running costs as the maintainence has been shown to be no higher than petrol engines, either type of engine wears out well past the other drive train parts which are common to both. That's comparing identical models available in both engines, slightly higher upfront cost, lower operating costs. Which applies to hybrids, higher upfront cost for promise of lower operating costs.
One of the auto associations here puts out a broad (but somewhat shallow) analysis:
https://rac.com.au/car-motoring/info/buying-a-car/running-costs
For the typical 15,000km/year and mixed city/highway driving that normal people do, the life-cycle cost of any engine choice petrol/diesel/hybrid ends up lost in the noise. People need to be heavily biased toward/away from long distance highway driving, or much higher/lower km use for any difference to appear.Where these 'running costs analysis' go wrong is by looking at the first few years only. Spending over 500 euro per month on a car? You've got to be friggin' kidding me. If you are going to look at craddle to the grave, you'll see an entirely different picture. It takes a very careful selection to find that car that has really low costs. The first step is to buy a used one which is 6 to 8 years old with around 125k km 'on the clock'; that way most of the devaluation has been eaten by the previous owner(s). The second step is to figure out whether the typical problems are simple (and thus cheap) to fix. Ofcourse it helps that I'm in a country where you can buy cars that are produced in Germany and are of decent quality to begin with.
And diesel is just dead. Just because of the pollution associated with diesel it is not a good choice. In addition to that diesel engines have become extremely fragile and expensive to repair/maintain. Look at prices for replacing the particle filter for example and problems due to internal pollution of a diesel engine. My previous car was a turbo diesel from 1999 with exhaust recirculation (EGR). The latter caused a buildup of 1cm of oil and sooth inside the air intake manifold. It was difficult to get that cleaned out. Fortunately it was possible to close the EGR to stop sooth getting into the intake but you can't do that on modern diesels. At the end the fuel injection pump (Denso, not some kind of crappy brand) started to have issues. Currently I'm driving a car on gasoline which has far exceeded the mileage of my previous 3 diesel cars and is still going strong while being very cheap to run (around 21 eurocents per km). Again: careful selection. When looking for my current car I started with looking at diesels but quickly found out that these are prone to very expensive repairs and most cars for sale needed such expensive repairs.
Currently I'm looking into a new (used ofcourse) car and I keep getting back to the hybrid Toyotas for the lowest cost per km. Downsized engines do offer a much better fuel economy compared to my current car but these are also prone to expensive failures or are just expensive to maintain (like 1200 euro for changing a timing belt which is buried deep inside the engine and needing special oil). Many cars just aren't designed to last more than 5 years and/or being maintenance friendly nowadays.
That depends on the type of hybrid; the only hybrids to consider need to have a true Atkinson cycle engine. Such engines are much more efficient so even on highways, you'll get a much better mileage compared to a conventional ICE based car. Unfortunately there are only a few manufacturers that make such hybrids (typically with a drive train from Toyota).
That depends on the type of hybrid; the only hybrids to consider need to have a true Atkinson cycle engine. Such engines are much more efficient so even on highways, you'll get a much better mileage compared to a conventional ICE based car. Unfortunately there are only a few manufacturers that make such hybrids (typically with a drive train from Toyota).
A 'true Atkinson cycle engine' is an entirely different animal and not something you will see in any modern car. Modern "Atkinson' and 'Miller' cycle engines are simply marketing designations for regular Otto-cycle engines with modified valve timing and higher compression ratios (as calculated from swept volume and combustion chamber size). Yes, these setups can be significantly more efficient at the cost of reduced power (for a given engine size) and limited operating range, but the name is just that and nothing more. Many modern engines, including non-hybrids, use variable valve timing and lift along with mechanical compression ratios higher than would be otherwise workable to achieve similar results under the right conditions.
If you think modified valve timing does not produce a "true" Atkinson cycle, you aren't grasping the nature of the Atkinson cycle.
If you think modified valve timing does not produce a "true" Atkinson cycle, you aren't grasping the nature of the Atkinson cycle.
I fully grasp the concept of the Atkinson cycle and I don't want to debate the details with you and I don't know what you mean by 'power ratio' anyway. The actual result is simply that the exhaust temperature is lower, meaning more energy has been extracted than would be otherwise. However, none of that is my point--what I was pointing out is that many engines today use this general method of increasing efficiency but only a select few market it as an 'Atkinson cycle' or 'Miller cycle'. Therefore, IMO, making your purchasing decision based on whether the marketeers have attached this particular name to the product is not helpful.