i wonder if there is anyone can advise me im picking up my new rex tomorrow and have a 110 mile drive home when should i turn the rex on the first 20 miles is in london the next 70 on A roads the last 20 back roads. any help would be grateful.
pick up new car tomorrow
- Thread starter busaman
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rtanov
Well-known member
Turn it on when you get out of town (and under 75% battery charge) and then off when you are sure you can get to destination on battery power. Make sure the dealer has the car fully charged at delivery. Way to start the New Year, congratulations!
BoMW
Well-known member
Also bare in mind about the time taken for the hand over. The i genius will brief you about the cars functionality while powered up so an hour later your battery can deplete.
Switch on Rex when first battery bar is empty (75% left) and if you are reluctant to stop for petrol you can always fill up a 5 litre tank and store it in the frunk
Switch on Rex when first battery bar is empty (75% left) and if you are reluctant to stop for petrol you can always fill up a 5 litre tank and store it in the frunk
pdurham
Well-known member
I'll assume there are no sustained climbs on your route. I'm not aware of any mountain passes near London. 
This is just my practice: On a trip like you described, I use the REx only on the freeway portion, saving the battery for cities, towns and back roads, and I try to finish the trip with the battery down to the 6.5% SOC point where the REx comes on automatically (so that I've used the battery range fully). I have two reasons for this. One is aesthetic--the noise and vibration from the REx is less noticeable at higher speeds and much more noticeable in cities and towns. The other is based on a theory I have about electric range. It's a little hard to explain succinctly but here goes . . . . My objective is to use the battery when I'm driving most efficiently so as to maximize the miles covered from battery power and minimize the amount of gas I use. My theory is that greater wind resistance due to higher freeway speeds has relatively less impact on gas consumption when the REx is on than it does on the consumption of electricity from the battery when the REx is off. Put another way, freeway speeds drain the battery much more quickly than slower driving. But if the REx is going to be on in both situations, it's going to be using similar amounts of fuel notwithstanding the different speed of travel. I know, the REx has different speeds of operation depending on the car's energy demands, but my theory is that the impact of the different REx operating speeds on fuel consumption is not huge compared to the fuel consumption, zero, when the REx is off. So, if this theory is correct (and it is only a theory at this point), I maximize the total miles covered using battery power and minimize the gas consumption and time the REx operates by using the REx only for the higher-speed portions of the trip. If your response is that I'm thinking this to death, you're probably right! I take an identical 200-mile trip every two weeks, so I suppose I could test this theory but I haven't gotten around to it yet (and may never).
This is just my practice: On a trip like you described, I use the REx only on the freeway portion, saving the battery for cities, towns and back roads, and I try to finish the trip with the battery down to the 6.5% SOC point where the REx comes on automatically (so that I've used the battery range fully). I have two reasons for this. One is aesthetic--the noise and vibration from the REx is less noticeable at higher speeds and much more noticeable in cities and towns. The other is based on a theory I have about electric range. It's a little hard to explain succinctly but here goes . . . . My objective is to use the battery when I'm driving most efficiently so as to maximize the miles covered from battery power and minimize the amount of gas I use. My theory is that greater wind resistance due to higher freeway speeds has relatively less impact on gas consumption when the REx is on than it does on the consumption of electricity from the battery when the REx is off. Put another way, freeway speeds drain the battery much more quickly than slower driving. But if the REx is going to be on in both situations, it's going to be using similar amounts of fuel notwithstanding the different speed of travel. I know, the REx has different speeds of operation depending on the car's energy demands, but my theory is that the impact of the different REx operating speeds on fuel consumption is not huge compared to the fuel consumption, zero, when the REx is off. So, if this theory is correct (and it is only a theory at this point), I maximize the total miles covered using battery power and minimize the gas consumption and time the REx operates by using the REx only for the higher-speed portions of the trip. If your response is that I'm thinking this to death, you're probably right! I take an identical 200-mile trip every two weeks, so I suppose I could test this theory but I haven't gotten around to it yet (and may never).
PhilH
Well-known member
BoMW said:
Should be easily able to do this journey without filling up.
I was due to collect mine tomorrow in Lincoln but I was advised that a new software update is released tomorrow which will extend the range, so I'm waiting until Wednesday to collect mine. If you have the new upgrade already, then your range may not be such an issue. I doubt you will get 110 Miles on battery but you shouldn't need too much Rex.
BoMW
Well-known member
I've done 14500 miles on my Rex, much of it motorway driving. 110 miles should be possible on ecopro mode (65-70mph) with approx 60 miles on Rex and 50 on battery. Would be good to hear details of your trip, enjoy!
nowtta60
Well-known member
I'm pretty sure running the rex on high speed sections is the right approach. IIRC gas engines operate more efficiently at wide open throttle / full power. Although consumption is at maximum too, the kw produced for the amount if fuel used is higher. If the rex is running and just ticking over turn a lot of the power is being used to overcome the internsl resistance etc.pdurham said:
@Busaman. I'm pretty sure if you set the nav to your destination and have the REX on hold SOC mode it tells you when you are in range of completing the journey on battery only so you can switch it off again. Not got mine yet but know I read that somewhere. You wont be able to switch it on till charge is down to 75% so the first part will have to be on electric. Which is great for people living in London with asthma and other lung conditions.
nowtta60
Well-known member
BoMW said:
Love the sig, but what are port holes? I'm presuming you don't mean fenestration that is sea worthy.
BoMW
Well-known member
nowtta60 said:
No, those small openings that they call a sunroof!
PhilH
Well-known member
busaman said:
Doesn't sound too bad at this time of year. Depends how much you were heating the cabin and how fast you were going on the A12.
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