Per request, I'm posting some tips and tricks on how to get a better range out of your Cmax in cold weather as well as during the warmer climates. This is strictly for EV driving no ICE involved.
1. It goes without saying, as much as you may cringe, electric heat kills the battery range. This is the #1 factor of range reduction. The best way around this is to not use any heat. If you decide to go this route, then:
a) dress for it, in layers upper and lower section of your body, no different than walking outside for extended distances to walk from the train to work for example. Don't forget the gloves, maybe even a scarf and a hat.
b) Windows tend to fog up in cold weather without the climate control running, to counter this effect you can either apply some rain-x anti fog to the windows and/or crack both front windows to circulate some air in the cabin. Cracked windows don't need to be much, just 1/4 inch or so on each front side is sufficient.
c) heated seats are a good option and do not take much power at all, in fact feel free to use them when necessary, but, like anything else, once your seat warms up if you think you can do without for the rest of the trip then turn them back to 1 or 2 setting or off if the weather permits, the sun is out, etc. Remember its a matter of range, so if you're sure you're going to make it, don't be as frugal.
d) if you have the moonroof, keep it open in the winter to let daylight in, as any sunlight will improve the cabin temperature to more comfortable levels.
Know that driving without heat comes with practice, in other words you're not going to go out and drive cold turkey in the dead of winter at 20F. Its best if you work up to it, meaning you drive without heat all fall and into winter, as you will get used to a colder car over time and before you know it driving in 30 degree weather is not even noticeable. The hardest days would be the single digit ones in the dark, but if you triple layer it knowing you're going to be out that night, it will certainly help.
2. Now that we got by the heat part, how can you increase the range even further. You next thing is to drive in the daytime if possible, for at least 1 leg of the trip. In other words if you're going out to dinner, try to leave the house before it gets dark so you can get to the restaurant without having to use the headlights. Headlights rob anywhere between 10 to 20 mpge from your battery performance. High beams take on the order of double the power, and fog lights add about 1/2 draw over the headlights. This is approximate. Remember this and use your lights when you need to, but skip the fog lights if not necessary and don't ride around with high beams for extended periods of time, which brings up the next tip.
3. Slow down. Since you're not using high beams, you can't see as far but if you're going slow enough you won't need them. Ideally stick to speeds of around 30 to 40 mph. Remember that the car is always "burning battery" when powered up, so you want to get there but your don't want to go too fast either as it will drain the battery faster and yield less miles due to drag. Under 20 mph is probably too slow and counter productive, over 40 the wind drag is starting to dig into your range. If you need to take a section of the highway, do so but remember you can't go as far at higher speeds. However, a good speed in EV mode for the highway would be somewhere between 45 to 55 mph. Depends on traffic, your battery % and distance to home is how fast you can go. If its late at night and you need every mile you can get in EV, go 45mph in the right lane (minimum speed). If you have to keep up with traffic, shoot for 50 to 55 tops. Or, take the country road. Remember always that the shortest way to your destination is probably the best way since you will be going slower (secondary roads) and its less miles so you can make it on EV power. Don't worry about traffic, if you have to go 35 instead of 45 on a secondary road because of traffic, great, then you're going further and not feeling like you're holding anybody up.
4. Regen all you can. This means you should be shooting for 100% brake scores all the time. I've attached a picture of my return trip from Worcester back home tonight, over 25 miles and even at 33 degrees outside and running at night, I had 7% main battery left. How can you do this? Don't follow anyone too close, look ahead and anticipate/react early. If the light in a distance turns yellow, do not step on the accelerator any more, let the car coast up to the light. If the distance to the light is too far, try to see the other crossing light to detect when it turns yellow. Add a little power to continue slowing down but stretching it, you're trying to either get there with some speed left if the light turns back to green, or get there with no speed and minimum brake needed if you have to stop (still red). Any speed you preserve helps with your range (not having to stop all the way). If the light is not that far and just turned yellow, brake immediately and brake lightly all the way to the light. Milk it so that you use up all the distance to the stop line or the car in front of you. If possible switch lanes to the side where you can brake further (less cars in that lane in front of you) to gain more regen and better your chance at a 100% brake score. You have to adjust the brake pedal pressure very gingerly and know from experience given your speed, the incline, and the distance to target (stop area) to know how much brake pressure to apply or release. Sometimes you might need to let up on the brake slightly so that you will still be regenning all the way to the stop, other times you have to increase pressure slightly to be able to stop. Your mission is to get 100% brake score, if you scraped the pads, you make a mistake, learn from it.
5. Use cruise control. Even on secondary roads, almost everywhere except where heavily congested, not only for the highways. It helps take the load off you of having to feather the gas to keep the car going. For long distance and given time (not in a rush), I select a speed of about 38mph. This gives a good balance between getting there and extending your range. Learn to turn off CC with the button (not the brake) and back on as needed. However, when you turn it on, do not do so at a slow speed and let it pickup rather aggressively to your target speed, I prefer to accelerate the car myself to within 3mph of the target speed and then turn CC on.
6. Speaking of accelerating, always use the Empower screen (in auto mode) so you can see the bars. Use no more than 2 bars to get up to speed, but if there is time or no traffic behind you, then use 1 to 1.5 bars depending on the incline. If you're at a light and its slightly downhill in front of you, use 1 bar. If its level, go with 1.5 bars. If its uphill, like an on-ramp to a highway, 2 bars tops, NO matter what don't go over 2 bars. Only CC is allowed to go over 2 bars in my opinion and it might hit about 2 1/4 bars tops to go up a hill. The longer you take to get to your desired speed, the more efficient you will be. If you're faced with a hill, don't be afraid to allow the car to slow down as you climb it. Sometimes 2 bars you might lose some speed, other times you might do it on purpose and only power up at 1.5 bars to lose some speed (if no-one is behind you for example or you need to turn off at the top). You can always regain the speed back on the downhill part, but slowly as well. Don't try to accelerate up the hill back to your speed, wait until the road levels off and keep the same power (1.5 bars for example) in until the car picks back up on its own.
7. Maintain your speed because of drag. What does this mean? If you are in CC going 38mph and you are the top of a hill and starting to do down it, what do you do?
a) you let it be and have the car run away to 50mph on its own and then slow back down to 38
b) you engage hill decent mode and let the car accelerate to about 41mph and hold its speed
c) you engage L and don't allow the car to get much past 39mph and shift back to D as the hill shallows up.
Choice B or C will get you the furthest on the same amount of electrons, because drag at the higher speed of 50 will dig into your final distance that you can travel on the entire battery. Why B or C? Well B usually does pretty good in holding the speed unless the hill is quite steep, the C would be best as its max regen and tends to hold the car closer to the desired speed. B is variable, but I felt that its not as tight as L in holding the speed to a set point. The difference between B and C is minimal, so to keep it simple use B instead of A for better results. C is not required if the hill is shallower, and if real shallow D alone in CC would be OK. You will have to learn to judge what you need when.
8. Accelerating from a stop goes without saying that you should pull out gingerly. In this car its best not to try to pull out into oncoming traffic, you know, they type where you know you can beat the car coming down the road. Any hard acceleration from the start is easy to come about when you are trying to pull out quicker than granny slow and also will dock your acceleration coach. Speaking of the coaches, watch those as part of your screens that you view. If you're doing ok they should be all full blue 100%. If any of them are down, work on that issue and learn to fix it. Trust the coach bars, if they are happy, your will go further in EV mode.
9. An extra bit of regen can be had by shifting to L from D during a full stop at about 6mph. This is because regen stops in D around 5 mph, and stops in L around 2.5 mph. By shifting to L you gain just a little bit more regen from 5 to 2.5 mph. This is also minimal and may add a 1/2 mile range for your entire battery pack, so I skip this unless I am going somewhere far which I know I can barely make it on a 100% charge, then I'll do this as well with every stop to help. I found that around 6mph shift to L gives the least amount of jolt, its almost seemless.
10. Don't be afraid to use L when necessary. This is especially true if you crest a hill and are faced with a steep downhill to a stop sign at the bottom. Immediately shift to L for max regen and pad the brake lightly at first to initiate regen around the battery (circles going around). At this point judge the distance to the stop sign and your speed/incline and increase brake pressure if necessary ever so slightly to milk it all the way down to the stop sign. This is the hardest challenge to get 100% brake score, too much braking and you dig into the friction pads and waste regen energy to the battery. Its not always possible to get 100% brake scores, but always aim for it. You can also use L while you're still learning to use the brake pedal (without friction pads) to slow down and take a left or right turn on a side street. Shifting to L gives you almost max regen and you just take the corner in L and shift back to D and keep moving. You'll need to learn when to shift to L, at what moment, so that when you arrive at the turn you're at the perfect speed you want to be at to commence the turn. Remember that L has no brake lights, so if someone is close behind you its imperative that you at least pad the brake just enough to see the regen circles around the battery indicating that your brake lights are on.
So what is a good range anyways? In the winter months when its bitter cold average temp of around 20, I was getting 22 miles estimated range -- that was the lowest I saw this year and we had one of the coldest and snowiest winters in Boston. In the summertime when its warm and ideal say 65 to 75F, then your expected range should be closer to 30. If you drive down the highway at 50mph, then the range should drop to around 27.
And what about preconditioning the car? Well for starters as far as the winter goes, I've totally abandoned the idea of warming up the car, only because its just wasted energy when I drive off the windows are cracked anyways and its not going to last long anyways in there. I'll only do it if there is ice or fog on the windows to thaw them out. However, in the summertime AC is not nearly as bad on range as electric heat, as a comparison, heat can pull anywhere from 5000+w on startup to around 2500 to 3000w to maintain, whereas AC can pull as much as 2500-3000w on startup but only about 625w to maintain. Due to this the best coarse of action in the summertime when its hot is to precondition the car with the AC until the drop can be seen in the climate meter (down to 625w), then unplug the car and take off with the AC on for the rest of your trip. In the evenings when its not as hot, you could skip the AC and open the windows instead or just use the AC if you know you will make it on EV power anyways.
It goes without saying, always bring your stock charge cord with you on distant trips where you could use it to recharge your car for the trip back home if there isn't any convenient public charger available. Don't forget an extension cable so you can lock the charger inside the car, unfortunately its not always safe to leave it outside unattended.
Edited by rbort, 19 April 2015 - 06:33 PM.