Two related but separate issues are often confused. One is how many miles the car predicts that you will get from a charge while the second is how many miles you actually do get. People have named the predicting the "Guess-O-Meter" or GOM because accurate predictions are almost impossible there are so many factors that will affect your actual mileage.
For example, every time I drive up the steep gravel road going to my house, the GOM is reduced by about ten miles more than the distance I have traveled. If I used the whole charge going back and forth on this road I would be lucky to get even 100 miles on a full charge. Similarly, if you drive at high speeds, in excess of 75 mph, your actual mileage on a full charge will also be much lower than the advertised 225 miles. Very cold weather will also reduce the range, both because the battery is less efficient at cold temperatures and I may use a portion of the battery to heat the car.
Alternatively, when I drive on the winding roads of northern New England between Vermont and Maine at speeds ranging from 40 to 55 mph, I might get as much as 290 miles on a full charge.
The GOM cannot know which of these kinds of driving I will be doing on the remaining charge, so it bases its prediction on the driving I have been doing.
Because of this variability in range, I do not focus on the GOM's prediction. But each time I am ready to charge at home, I check the percentage of charge remaining, compare it to the level of charge when I last plugged it in (for me usually 80% unless I am going on a long trip) and divide the miles I have actually driven since that charge by the percentage of charge I used. The resulting figure tells me how far I could have gone on a 100% charge with the recent conditions. If I were more organized I would keep a chart showing the range in different conditions, but for now I am satisfied with a general picture of how far I can go with different kinds of driving and weather.
Is that helpful?
Moderator -- I see the same question was asked in the battery and charging section of the forum. Perhaps the two conversations can be consolidated?
For example, every time I drive up the steep gravel road going to my house, the GOM is reduced by about ten miles more than the distance I have traveled. If I used the whole charge going back and forth on this road I would be lucky to get even 100 miles on a full charge. Similarly, if you drive at high speeds, in excess of 75 mph, your actual mileage on a full charge will also be much lower than the advertised 225 miles. Very cold weather will also reduce the range, both because the battery is less efficient at cold temperatures and I may use a portion of the battery to heat the car.
Alternatively, when I drive on the winding roads of northern New England between Vermont and Maine at speeds ranging from 40 to 55 mph, I might get as much as 290 miles on a full charge.
The GOM cannot know which of these kinds of driving I will be doing on the remaining charge, so it bases its prediction on the driving I have been doing.
Because of this variability in range, I do not focus on the GOM's prediction. But each time I am ready to charge at home, I check the percentage of charge remaining, compare it to the level of charge when I last plugged it in (for me usually 80% unless I am going on a long trip) and divide the miles I have actually driven since that charge by the percentage of charge I used. The resulting figure tells me how far I could have gone on a 100% charge with the recent conditions. If I were more organized I would keep a chart showing the range in different conditions, but for now I am satisfied with a general picture of how far I can go with different kinds of driving and weather.
Is that helpful?
Moderator -- I see the same question was asked in the battery and charging section of the forum. Perhaps the two conversations can be consolidated?
