Confused about petrol consumption

[Ruckman65]

I am looking to purchase a 2015 model and am confused about petrol consumption. In these scenarios, how much petrol would be consumed?

1. Highway driving at 100km/h for 100km
2. Travelling distance of 50kms where approximately half of that is freeway driving at 100km/h

I understand there are many variables but a ballpark estimate would be greatly appreciated.

 

[maby]

We had a 2014 model which was used primarily for highway driving. Once you have run the battery flat, you should be able to get around 44mpg or 6.5 ltr/100km out of it. If you are interested in overall fuel consumption, then you need to subtract your EV range from the 100km and then work out the fuel consumed using that figure. The primary uncertainty will be the EV range - the battery in a moderately used 2015 car will be showing its age and range could be getting quite low. Some here are willing to drive without heating or air conditioning and can stretch their range a bit. Personally, I'm not willing to use a car like that - I ran with heating or aircon as appropriate to the time of year and our 2014 car was showing an EV range of around 10 miles in the winter and 15 in the summer.

Martin

 

[Ruckman65]

We had a 2014 model which was used primarily for highway driving. Once you have run the battery flat, you should be able to get around 44mpg or 6.5 ltr/100km out of it. If you are interested in overall fuel consumption, then you need to subtract your EV range from the 100km and then work out the fuel consumed using that figure. The primary uncertainty will be the EV range - the battery in a moderately used 2015 car will be showing its age and range could be getting quite low. Some here are willing to drive without heating or air conditioning and can stretch their range a bit. Personally, I'm not willing to use a car like that - I ran with heating or aircon as appropriate to the time of year and our 2014 car was showing an EV range of around 10 miles in the winter and 15 in the summer.

Martin

Thank you for the advice, Martin. Most appreciated.

 

[kpetrov]

Like Martin have said, the easiest and correct way is to subtract electric mileage.
So pure engine consumption is like he said around 6.5L/100km at 95-100km/h and going up with speed increase.

if you make 50km on electric then on 100km your consumption will be half of previously mentioned numbers.

 

[Ecological]

I am looking to purchase a 2015 model and am confused about petrol consumption. In these scenarios, how much petrol would be consumed?

1. Highway driving at 100km/h for 100km
2. Travelling distance of 50kms where approximately half of that is freeway driving at 100km/h

I understand there are many variables but a ballpark estimate would be greatly appreciated.

Good news. I have owned a 2015 model from new. It has now done 44,000 miles ++. 100Km is 62 miles. That should technically be okay. Driving at 62mph is also okay in a PHEV.
Answer to 1: For 62 miles, you should still have some battery left [regardless of what the display tells you]. So for 62 miles, with a full charge at the start of your journey, you should achieve around 50mpg of petrol, [which includes the batteries].
Answer to Q2: Travelling at 50km which is 31.069miles, you should be able to get 140 to 150 miles per gallon with a full charge. ~At a speed of 62 miles for half of it, you should get around 50 to 70 mpg.
FACT: If your speed does not exceed 50mph, you should get 140 mpg for 32 miles, and evening it out as in Question 2, you should attain 140 to 200mpg if you travel some bits at urban speed, and some at highway speed provided it does not exceed 50mph.
Anything above 60 mph eg at 70mph, the above facts will not apply. At 70mph, your battery will exhaust in 8 to 10 miles, amd after that you a looking at 28 to 31 mpg.
Afteral at 70mph, the air becomes thick and it is like driving through water. At 120mph, the air will be akin to treacle..and you might get arrested for exceeding the speed limit!
Any problems come back to me.

 

[greendwarf]

Good news. I have owned a 2015 model from new. It has now done 44,000 miles ++. 100Km is 62 miles. That should technically be okay. Driving at 62mph is also okay in a PHEV.
Answer to 1: For 62 miles, you should still have some battery left [regardless of what the display tells you]. So for 62 miles, with a full charge at the start of your journey, you should achieve around 50mpg of petrol, [which includes the batteries].
Answer to Q2: Travelling at 50km which is 31.069miles, you should be able to get 140 to 150 miles per gallon with a full charge. ~At a speed of 62 miles for half of it, you should get around 50 to 70 mpg.
FACT: If your speed does not exceed 50mph, you should get 140 mpg for 32 miles, and evening it out as in Question 2, you should attain 140 to 200mpg if you travel some bits at urban speed, and some at highway speed provided it does not exceed 50mph.
Anything above 60 mph eg at 70mph, the above facts will not apply. At 70mph, your battery will exhaust in 8 to 10 miles, amd after that you a looking at 28 to 31 mpg.
Afteral at 70mph, the air becomes thick and it is like driving through water. At 120mph, the air will be akin to treacle..and you might get arrested for exceeding the speed limit!
Any problems come back to me.

Driving down the Autoroute to South of France on a number of occasions with a roof box at 85mph I was getting a fairly consistent 28mpg - if that's any help. The car is as aerodynamic as a 2 tonne house brick and although it was comfortable with the speed it was at the expense of fuel!

 

[Ruckman65]

Thank you all for your very helpful advice.

 

[evman77]

I am looking to purchase a 2015 model and am confused about petrol consumption. In these scenarios, how much petrol would be consumed?

1. Highway driving at 100km/h for 100km
2. Travelling distance of 50kms where approximately half of that is freeway driving at 100km/h

I understand there are many variables but a ballpark estimate would be greatly appreciated.

Your highway trip will be mostly on gas the entire way. I make that trip every week to golf in my 2019. I use between 7.5 and 8.5 L for 100 KM. I guess it depends what your fuel price is. I pay $1.75/Lt so just over $13CDN.

 

[Ruckman65]

Your highway trip will be mostly on gas the entire way. I make that trip every week to golf in my 2019. I use between 7.5 and 8.5 L for 100 KM. I guess it depends what your fuel price is. I pay $1.75/Lt so just over $13CDN.

Thank you, evman77. Very useful information.

 

[littlescrote]

Just be careful about figures quoting miles per gallon as a US gallon is different to a UK gallon.

 

[evman77]

Thank you, evman77. Very useful information.

before you purchase a 2015 you should be aware that;
ev range fully charged will be around 30KM
the ICE has no transmission like a regular car. It is hooked directly to the front wheels in what would be top gear.
If you are driving around town at less than 60kph the two electric motors will be driving the car and the gas engine will come on the charge the battery.

 

[Ecological]

Driving down the Autoroute to South of France on a number of occasions with a roof box at 85mph I was getting a fairly consistent 28mpg - if that's any help. The car is as aerodynamic as a 2 tonne house brick and although it was comfortable with the speed it was at the expense of fuel!

Your car is doing absolutely what it is designed to do!!! 28mpg at 85mph, is alsolutely correct, even when new. You will see miracles happen if you only halved that speed, and kept the car fully charged. You see some people [not you I am referring to!] think that if they charged the car fully, they will get 32miles range. No way hosey, if they say go at 90 mph. As in all things with energy and matter, the faster you go, the more battery power and fuel will be used. If you rolled the car down a hill, all the way, down 100miles, your Battery range may even be 100 miles, provided you do not brake or press the accelerator.....because little or no energy will be asked of either the battery or ICE. Unfortunately at 42mph, it will take you longer to get there! Fortunately in England, we have lots of temporary traffic lights, and pot hots, so travelling 15 miles there and back will make little or no difference if you dorve at 40 mph or 60 mph. I take it you do not get many temporary traffic lights in France. I think England can probably claim to have the most temporary traffic lights in the world from the 5 or 6 countries I have driven in! Thanking you warmly for replying.

 

[michael8554]

I agree with Ecological's opinion on UK driving conditions - high average speeds are very difficult to achieve.
Our 220 mile journey from Wiltshire to York to visit our son takes 5 hours, an average of 44mph.
By contrast, in France I used to drive 630 miles from Dunkerque (Channel coast) to near Avignon (SE corner of France) in 10 hours, an average of 63mph, on largely deserted toll Autoroutes.

 

[greendwarf]

Your car is doing absolutely what it is designed to do!!! 28mpg at 85mph, is alsolutely correct, even when new. You will see miracles happen if you only halved that speed, and kept the car fully charged. You see some people [not you I am referring to!] think that if they charged the car fully, they will get 32miles range. No way hosey, if they say go at 90 mph. As in all things with energy and matter, the faster you go, the more battery power and fuel will be used. If you rolled the car down a hill, all the way, down 100miles, your Battery range may even be 100 miles, provided you do not brake or press the accelerator.....because little or no energy will be asked of either the battery or ICE. Unfortunately at 42mph, it will take you longer to get there! Fortunately in England, we have lots of temporary traffic lights, and pot hots, so travelling 15 miles there and back will make little or no difference if you dorve at 40 mph or 60 mph. I take it you do not get many temporary traffic lights in France. I think England can probably claim to have the most temporary traffic lights in the world from the 5 or 6 countries I have driven in! Thanking you warmly for replying.

Interesting you say that, because my A-level physics (failed, lol) memory doesn't see why speed of itself should make any difference to energy consumption. Whereas wind resistance increases exponentially with speed, thus requiring more energy to overcome.

And to be fair, apart from a lower motorway maximum speed limit in the UK, once out of urban areas (which often seem worse in France) I generally find I can maintain a high average speed (70+) in the UK, without too much trouble.

 

[michael8554]

How do you average 70mph+ without breaking speed limits ?
I could get to York much quicker doing that :-<