RX450H+ EV range and ICE consumption

[Pally]

I’m very impressed, it’s great efficiency for a big car. EV efficiency was showing as 2.1kw/h when I got the car and it has steadily increased.

I don’t know about the sat nav coordination, that would be excellent if it could. For any longer trip I plan to use HV when at a steady speed on dual carriageways or motorways and EV when in built up areas and on slower roads. If remaining EV range matches sat nav miles to destination I switch to EV.  

That worked well on my last trip and I still ended up with a few 2-3 miles of EV left. 

For example my last trip was just a few miles in EV to get to the faster roads, a long stretch of HV, then I used the rest of the EV range through Taunton and on to my destination on country roads. 

On the way back I did it in reverse, twisty roads and Taunton in EV, faster roads in HV and then switched back when remaining distance matched EV. It works really well.

Probably just saying what you all know!

Does anyone switch between modes more often as a driving technique or do most people keep it simple?  

[Xez]

Hi Pally, I do as you do… and find that this appears to give the best of the two modes 😀

[Xez]

21 hours ago, MrBee said:

That sounds really impressive. 

I think I read somewhere that Audi (I think?) have a system in their phev that analyses your proposed route and works out the most efficient way to deploy the battery. I don't suppose the RX has this? 

Or maybe it's more clever than that and is effectively doing this continuously? 

Hi MrBee, according to the Lexus magazine the car is equipped with Predictive Efficient Drive technology. I quote a section of the blurb below. If like me you use apple or Google Maps I don’t think the cleverness is applied!

How does it work?

With the help of the Lexus Link app, selected Lexus hybrid and plug-in hybrid electric vehicles with embedded navigation systems will be able to learn a driver’s regular routes and driving style, while simultaneously looking ahead via live traffic data to anticipate opportunities to save fuel. More economical driving is automatically and seamlessly achieved by optimising the charging and discharging of the Battery on hybrid models, and the use of full-electric or hybrid modes on PHEV vehicles.

[Muff12]

On 2/16/2024 at 6:29 PM, Ken R said:

Anybody willing to share what they are achieving in m/KwH and fuel consumption when using the ICE on their RX450h+ to see how it compares with the equivalent NX?

I'm curently getting 2.5m/Kwh and because I mainly do relatively short journeys, I only tend to use it in EV.  My trip summary since last reset is 176.2 miles of which 172.3 is on EV (98%) which gives an impressive 649.3mpg!!

[MrBee]

1 hour ago, Xez said:

Hi MrBee, according to the Lexus magazine the car is equipped with Predictive Efficient Drive technology. I quote a section of the blurb below. If like me you use Apple or Google Maps I don’t think the cleverness is applied!

How does it work?

With the help of the Lexus Link app, selected Lexus hybrid and plug-in hybrid electric vehicles with embedded navigation systems will be able to learn a driver’s regular routes and driving style, while simultaneously looking ahead via live traffic data to anticipate opportunities to save fuel. More economical driving is automatically and seamlessly achieved by optimising the charging and discharging of the battery on hybrid models, and the use of full-electric or hybrid modes on PHEV vehicles.

That's impressive. Better than I thought. 

How is the in-built satnav? I use waze on the rav4 as the built-in system is poor. 

[Ken R]

23 minutes ago, MrBee said:

That's impressive. Better than I thought. 

How is the in-built satnav? I use waze on the rav4 as the built-in system is poor. 

I actually use the built in navigation and find that it is OK.

[Xez]

4 hours ago, Ken R said:

actually use the built in navigation and find that it is OK

Hi Ken, have you noticed the car being “more intelligent” in using the Auto switching between HV and EV? I tried using the Auto button but the car depleted the EV range then switched to HV, not saving any Battery power for when I reached urban conditions at the end of my journey. Hence why I manually switch between the modes.

[Ken R]

23 minutes ago, Xez said:

Hi Ken, have you noticed the car being “more intelligent” in using the Auto switching between HV and EV? I tried using the Auto button but the car depleted the EV range then switched to HV, not saving any battery power for when I reached urban conditions at the end of my journey. Hence why I manually switch between the modes.

Hi Kevin 

If I am doing a long journey I tend to manually switch, particularly on entering a motorway section. It's surprising how often the EV cuts in and I reckon its doing this more frequently than on the NX.

[Pally]

Hi Kevin/Ken

I read the same that Auto will prioritise EV and only add engine if you ask for more acceleration so it will quickly deplete the EV Battery on a long trip and not save for later.

I’ve opted for the same as you both and to manually switch between HV and EV 

Ken are you saying that while in HV mode the EV kicks in?  Is that just the standard hybrid functionality so essentially just the car operating as if the EV was depleted? Or are you seeing the EV range drop while in HV mode?

I’m about to set off for a 150 mile trek so will have another chance to test! 

[Ken R]

Covered a 50 mile round trip today of which 49.5 miles were achieved entirely in EV mode (journey started with an indicated 44) which is my best performance yet. One third of the journey involved motorway travel so pleased overall with this result.

[Pally]

That’s impressive; especially with the motorway miles. I have a similar starting mileage showing at the moment and have found I get more than the suggested level.

I’m showing 3.1 miles kw/h now overall which I’m also impressed with. 

[Tom,]

MPG in HV only mode:

I wanted to know what MPG my RX450h+ was achieving when using petrol only. So rather than attempt some devious calculations, I decided to actually measure it!

So during a week away from home I ran the car in EV mode until the Battery was depleted and it switched permanently to HV mode. I then topped it up with petrol and zero'd the mileage trip. I then drove 189.2 miles on non-motorway South Devon roads and again topped it up with 19.6 litres of fuel. If my calculations are correct, this gives a figure of 43.9 mpg. During this period I did not charge the Battery.

Not bad!

Tom

[Ken R]

Hi Tom

Thanks for this.

I'm going to do the same exercise later this month and will report thereafter but expect a result in the mid 40's as you have proved which is excellent for the size/weight of the RX450H+.

[Ken R]

Quick update on overall fuel consumption. Just filled the tank prior to a long journey today (only my second refuel since taking delivery of the car in March) and on a straight mpg basis I am getting 143.25 miles to the gallon. When including the cost of electrical recharges (overnight charge rate) and converting that to current price of fuel the overall is 95mpg which is considerably higher than the 61.96mpg previously reported. Absolutely delighted with this result and much better than the 77 that I achieved latterly with the NX.

[Ken R]

On 6/6/2024 at 6:53 PM, Tom, said:

MPG in HV only mode:

I wanted to know what MPG my RX450h+ was achieving when using petrol only. So rather than attempt some devious calculations, I decided to actually measure it!

So during a week away from home I ran the car in EV mode until the battery was depleted and it switched permanently to HV mode. I then topped it up with petrol and zero'd the mileage trip. I then drove 189.2 miles on non-motorway South Devon roads and again topped it up with 19.6 litres of fuel. If my calculations are correct, this gives a figure of 43.9 mpg. During this period I did not charge the battery.

Not bad!

Tom

I have completed the first stage of a similar exercise and after a 313 mile dash south principally on the motorway I refuelled and on a brim to brim calculation I'm getting an amazing 51mpg. Dashboard indicating 48.6.

[Tom,]

Ken,

I've just had another 10 days away from home with no charging capability.. After the Battery had discharged and the car had switched itself permanently to 'HV', I ran it around the Cornwall roads for a week and the dashboard indicator settled on 51 mpg, so it confirms your figures, which I think is pretty amazing for a large car.  The high mpg must be down to the self charging capability when going down hill, I reckon.

[Ken R]

On 6/27/2024 at 6:02 PM, Tom, said:

Ken,

I've just had another 10 days away from home with no charging capability.. After the battery had discharged and the car had switched itself permanently to 'HV', I ran it around the Cornwall roads for a week and the dashboard indicator settled on 51 mpg, so it confirms your figures, which I think is pretty amazing for a large car.  The high mpg must be down to the self charging capability when going down hill, I reckon.

Hi Tom

That's very interesting and very much in line with my outcome so agree that the results we are reporting are pretty amazing! My overall consumption for the round trip (c900 miles) without any charging finished at 50.68mpg (brim to brim). The dashboard was showing 50.1. The bulk of the mileage was motorway (M64/M6/M55) at speeds of 50-70mph which makes the result even more pleasing. Having previously owned a NX450h I never achieved as good economy as this!

[Spottedlaurel]

I'm not sure if there's an easy answer to this question, which hopefully makes sense, but....

Given that the PHEV model has a Battery capable of offering much more range than a normal hybrid (which I'm used to making the most of in my 2014 RX), once it has exhausted its range in EV could it theoretically be fully recharged when braking, going downhill etc?

Unless able to take advantage of a very, very long hill then this may not be possible, but will the system top itself up to give more range than a conventional hybrid?

Just wondering if that's part of the reason that some of you getting 50+ mpg. A more efficient 4-cyl engine and newer hybrid system I imagine are also a significant factor.

[Tom,]

Nigel,

I'm sure you are right and having also previously owned an RX450h non-plug-in mild hybrid, it seems that the 450h+ PHEV, with an 18KWh Battery and a smaller engine is considerably more economical. While driving in hybrid mode, I could see from the dashboard indicator that, on down hill driving, the traction Battery was charging and would then go automatically into EV mode. The Battery never got above 3 or 4 bars on the indicator which I guess is 20 or maybe 30% charged. 

I was expecting it to be inferior to the old RX for caravan towing with its 3.5 litre V6, but no such problems and it tows just fine. The figures I quoted are for solo driving of course, not towing.

It's a very clever vehicle and is surprisingly economical.

Tom

[Spottedlaurel]

Thanks Tom. Difficult to know what the future holds and whether I'll have the funds available as I near retirement, but the RX450h+ is certainly on the list for the eventual replacement of my current model.

[Pm4]

On 6/28/2024 at 10:16 PM, Ken R said:

Hi Tom

That's very interesting and very much in line with my outcome so agree that the results we are reporting are pretty amazing! My overall consumption for the round trip (c900 miles) without any charging finished at 50.68mpg (brim to brim). The dashboard was showing 50.1. The bulk of the mileage was motorway (M64/M6/M55) at speeds of 50-70mph which makes the result even more pleasing. Having previously owned a NX450h I never achieved as good economy as this!

Hi Ken,

I am intrigued to understand how the RX can achieve better results than the NX being the same power train but on a bigger and heavier car. Could it be a better drag coefficient or is it a car that is generally driven slower? 

Cheers. 

[Ken R]

4 hours ago, Pm4 said:

Hi Ken,

I am intrigued to understand how the RX can achieve better results than the NX being the same power train but on a bigger and heavier car. Could it be a better drag coefficient or is it a car that is generally driven slower? 

Cheers. 

I'm unsure as to the reasons but having kept a detailed log of all refuelling/recharging on both the NX and the RX this is the result. Perhaps given the size of the RX I am driving more slowly or there have been efficiency tweaks to the engine/battery over time. I do notice that the hv mode cuts in far more often on the RX. Certainly very impressed by the results.

[Tickedon]

7 hours ago, Pm4 said:

Hi Ken,

I am intrigued to understand how the RX can achieve better results than the NX being the same power train but on a bigger and heavier car. Could it be a better drag coefficient or is it a car that is generally driven slower? 

Cheers. 

Lexus Canada website specs shows both NX and RX are 0.35cd… so identical in that regard!

[RXtoNX]

5 hours ago, Ken R said:

I do notice that the hv mode cuts in far more often on the RX. Certainly very impressed by the results.

Interesting that you should say that Ken. Our NX450 goes in for its 2nd year service shortly and one thing I have mentioned to the service team is that it doesn’t really seem to go into EV mode when running in hybrid mode on petrol.

For the first 12 months it used to switch between fuel and EV when in HV and would regularly give 50mph plus on long journeys after the initial Battery charge had depleted. These days it only gives 45mph plus.

[Ken R]

3 hours ago, RXtoNX said:

Interesting that you should say that Ken. Our NX450 goes in for its 2nd year service shortly and one thing I have mentioned to the service team is that it doesn’t really seem to go into EV mode when running in hybrid mode on petrol.

For the first 12 months it used to switch between fuel and EV when in HV and would regularly give 50mph plus on long journeys after the initial battery charge had depleted. These days it only gives 45mph plus.

Worth getting this checked. I ran the RX in purely HV mode for a week covering c900 miles and Lexus Link is showing that the car was using electric power for an average 60% of 32 individual journeys including motorways.