Kash Bagal
Member
- Joined
- Jul 21, 2024
- Messages
- 8
Interesting point. Let me see if I can provide an explanation - though some members with more knowledge can perhaps provide additional information.
When this car was developed from 2007 - 2013 in Germany, there were very few charging stations. This car worked well within the city if it was charged each evening and would only be used in the city as a commuter car. However as soon as you would want to travel from city to city or for overnight trips, they saw the need for a Range Extender. In Europe, the Range Extender was able to be started at any percentage below 75%. And it came with a 9L (1.84 gal) gas tank.
As I understand it, when BMW decided to sell it in the US (I am in Canada so this info is based on my readings) the US government had promotions with grants for electric cars at the time. In order to qualify as a pure EV, they said that they would not approve it if the gas tank was over a certain size and if the gas tank could be used regularly or on demand. Thus in order to sell the car in the US and qualify as an EV along with the corresponding grants for buyers, BMW was forced to limit the size of the gas tank to 7L (1.84 gal) and the Rex could only come on at 6% of battery life. So the first thing that US and Canadian buyers would do was override the software limited settings to increase the gas tank to 9L and be able to turn on the Range Extender at any point below 75%.
Why is this important? Because I can tell you from experience, if you are not close to a charger, it is very unnerving if you only have 6% battery life left. If you happen to be on a highway and are going 120km/hr (75 miles/hr), the Range Extender cannot keep the battery charged and you start losing some of the capacity and soon you will be at 5%, then 4%, then 3% and since the car is an EV, even if you have gas, the car will stop at 0% battery life.
We have been driving the i3 for 6 years and we have been educating people on EVs since we got our 2 i3s. When asked about range anxiety on long trips we usually ask them how many long trips they take a year. When they say 3 or 4, we tell them that they will save so much money with EVs in a year that for those long trips, if they are still concerned, they can rent a gas car for those trips, and they will still come out ahead at the end of the year.
So for the 3 or 4 long trips we do each year, I use that same thinking with our i3 Rex, and instead of renting gas cars, we simply use it a gas car. I turn on the Rex at about 74%, and just use gas from that point onwards. It saves time since it only takes 2 mins to fill up the 9L gas tank every 100km (60 miles) or so and you are back on the road.
On a recent trip from Ottawa to Hamilton (500km - 300 miles), I turned on the Rex at about 74% and filled up every 100km or so, and since I was going about 120km/hr (75 miles/hr) by the time I got to Hamilton, I was down to about 60% charge left. I cannot imaging waiting to go down to 6% before the Rex came on - I would have to reduce my speed to about 90km/hr (55 miles/hr) in order for the Rex to maintain the charge. I am sure I would be getting looks from other drivers and it would have taken much longer to get to my destination. And if we had decided to use the car only as an EV, which we have done many times in the past, we would have had to plan the trip to visit multiple charging stations since the i3 battery is now getting lower, and at each stop we would have to hope that the charger is working and/or there is not a long line up making up for a long stop - both conditions which we have experienced in the past making for an even longer trip.
I am not saying that this is the best or only method but it is how we use the Rex, and there are many others who also use this method. We do not use the Rex in the city at all.
Hope that provides some explanation.
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