Well, wether you follow news about electric vehicles (EVs) or not, it is very likely that you have heard this week some serious bashing of EVs and their questionable usability in COLD weather as the nation is plagued with its first major arctic blast of cold air. They even like to use magical sounding names like "Polar Vortex" to make "it's cold" sound special. There are some truths to what the media will say, but most of it is just utter rubbish and I have had just about enough of it all.
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This blog subject formulated in my mind as we were doing the first leg of a 500+ mile round trip back to my hometown on Tuesday morning in our 2021 Tesla Model Y LR. We left at the tail end of our first snowstorm in 2 years which left most of the roads a slushy mess near home with temps in the low 20's. Endured on and off snow squalls, freezing drizzle/fog, a minimum of 11 degree, and arrived about 5.5 hours later with temps around 15 degrees. The entire time, I was glad, no, thrilled that we were driving the Tesla and not my wife's 2020 Mazda CX-5. Although the Mazda is AWD, it has all season tires and the Tesla just has superior traction in the snow and ice.
This blog was likely going to happen once I saw what happened in Chicago and became locked in once a family member, who saw my Tesla in the driveway while I was visiting say to me "I thought EVs didn't work in the cold"? First, what a dumb question to pose as my EV clearly worked fine enough to get me complete across the state with temperatures in the teens. Second, I realized this is what the general public is constantly fed, lies about EVs when the truth is, we were able to travel over 250 miles without any issues at all.
So, it seems fitting that I have chosen to start to write this on a cold, snowy Friday morning here in SE Pennsylvania (taking a mental health / snow day) where temperatures are in the mid-20's and much of the nation (graphic below) is well below Freezing and a huge portion of the upper mid-west is at 0F or below. BRRRRR... So let's get into the specifics of some of the lies and truths associated with EVs and Cold Weather. Grab some coffee and a snack, this is going to be a long, nerdy post.
Graphic above credit to www.wunderground.com
Cold Weather and EVs According to the Media
It is TRUE that EVs lose range when temperatures drop.
It is TRUE that SOME EVs charge more slowly in cold weather. Not ALL of them though.
... and this is about all that the media gets correct about EVs and cold weather. Everything else they say beyond this is basically an extreme exaggeration that is either intentional or due to ignorance or just a flat out lie. All of this FUD (fear, uncertainty, doubt) about EVs and cold wether is total BS, and I get it, these sorts of fear mongering stories get a ton of clicks and clicks = revenue. I also speculate that it is also likely that these "news" organizations and bloggers get a majority of their funding from the OEM automakers who have discovered they cannot compete in the EV space right now, and that they benefit the most by slowing down the rate of EV adoption. The more these lies get traction, the slower the EV adoption might happen.
It is TRUE that EVs lose range when temperatures drop. In fact, EVERY vehicle on the planet will have less range when temperatures drop, its just that it is MORE noticeable in EVs because they are so energy efficient to start with, that any additional load on the battery will have a bigger impact. I also attribute this larger sensitivity to EV range loss to the EV drivers themselves. I am willing to bet that many ICE drivers only ever look at their fuel gauge, F to E in 1/8th increments and if EV drivers only ever focused on SOC %, they really wouldn't care about cold weather range loss. Unfortunately, EV drivers have been conditioned to have range anxiety by the media and general public, and as such, these small impacts to their range are right in their faces all the time. Thankfully, as I discuss below, there are things that a driver can do to reduce the impact of the range losses.
It is TRUE that SOME EVs charge more slowly in cold weather. A battery is basically a huge, controlled chemical reaction that either produces or stores electricity. We all learned in chemistry class that chemical reactions often occur faster at warmer temperatures as long as the temperatures don't exceed a safety limit or range where the components of the chemical reaction might be damaged. As such, there are models of EVs, that have very complicated thermal management systems for the drivetrain to optimize the battery temperature for driving and charging performance. The vehicles that have these complicated systems generally experience no slowness in charging in cold weather conditions when they use them properly. It is the cheaper EVs (like the Chevy Bolt, Nissan Leaf, and VW ID.4) that don't have these systems that can experience a 2-5 times reduction in charging rates, and the media reports to the general public about these vehicles and never mentions all the other models that are working perfectly fine.
Unfortunately, it seems that only a fraction of EV owners are interested in knowing all the nuances and details about EVs and cold weather; and, as we have recently discovered in Chicago, many EV owners don't know the first thing about their EV, its thermal management systems, and how to properly use their EV in extreme cold weather.
Its about to get super nerdy, so buckle up if you are going to continue reading.
So let's start with this one. On social media, I have seen several different accounts quoting this study/analysis that has concluded that many of the popular EVs on the roads are seeing 30% reduction in range in near freezing temperatures (https://www.recurrentauto.com/research/winter-ev-range-loss). The biggest issue I see with these sort of alarmist articles and the people that share them is that they spin this as the end of the world and a reason that people should stop buying EVs. At a minimum, they use this as a reason THEY personally are not ever buying an EV without even trying to understand what is happening here. I am on a quest to convince people 4 things about this sort of data being shared by the media:
If you know nothing about your EV, and you just get in it and drive it, you probably will see at least a 30% reduction in range in certain models, but there are things that you can do to reduce the impact significantly which the media never mentions
But, even with 30% reduction in range, the way most people drive their EVs, this loss of range is going to have almost NO impact on EV drivers, and their daily driving habits. The biggest impact is that they might have to plug in every night or an extra night or two each week WHILE THEY ARE SLEEPING.
EV buyers need to be more informed consumers - know what you are buying and its limitations. Some EVs have heat pumps which are very efficient down to 20F, some do not. Some have complex thermal management systems, some do not. Consumers who live in or drive in regions which experience cold weather (below 50F) need to understand these things. Please do NOT trust the dealerships / sales people either. There are countless situations where Chevy and VW sales associates insisted their EVs have heat pumps when in fact they do not. Do your own research before buying.
Reduced range in the cold is a GOOD thing - You are going to have to believe me on this one, but having reduced range in cold conditions is actually a GOOD thing. What?! You are thinking in your mind righ now "Are you crazy Marc"? "Have you had a stroke"? But hear me out. All EVs that have sophisticated thermal management systems are doing everything within their power to get you to your destination as quickly as it possibly can. They are performing a very complex set of calculations to determine the right balance of energy it needs to get to the next charging station with the energy it needs to keep the battery at ideal driving conditions to accept regenerative braking power, which increases range, and the extra energy it needs to increase battery temperatures to prepare the battery to receive maximum charging power to get you on your way faster at the next charger. A vehicle that is dedicating energy to proper thermal management of the batteries will not only result in a better driving experience overall, it will also ensure less battery degradation long term.
Back to the linked study above. While I can agree that the data in this study is most likely accurate, the dataset includes ALL drives these vehicles took. Not sure about you, but for me, most of my drives are not long, but short, quick trips to work (10.5 miles one way) and running errands. This sort of driving behavior is very inefficient in every type of vehicle, EVs included, but in cold weather, there is way more overhead in the initial warm up and heating of the battery and cabin in an EV than in ICE vehicles (although EVs warm up way faster than any ICE I have ever owned). Just like this would mean an extra stop at a gas station in a given week during cold weather for an ICE vehicle, likewise, for those that charge at home, this would mean an extra plug-in or two at home during the week. As the EV owner though, you WANT this to happen (per last bullet above), because it means the car is attempting to get the battery warm enough to deliver and receive power efficiently. If the battery is too cold, max acceleration is not possible, regenerative braking might not be available, and most importantly, premature degradation of the battery is possible as energy is being pushed and pulled out of the battery at non-optimal thermal conditions. But the main takeaway I have after looking at this article from them, is that their dataset doesn't accurately represent the way EV owners should prepare and drive their vehicles when range actually matters. More education of EV owners is required by the way to get them to understand all of this.
Credit Recurrentauto.com
So let's start the education process. To understand this further, let's talk a little about how or how or where an EV uses energy, or more specifically, where it is using increased energy in cold, winter conditions. Driver understanding of these factors and then changing winter ownership behaviors in order to minimize the impact of these factors is the key to having an enjoyable EV ownership experience in the middle of a "Polar Vortex".
Initial Warm Up - When an EV is first turned on, not only does it use energy to attempt to warm up the cabin for the comfort of the passengers (1-3 kw), many of the better EVs have very sophisticated thermal management systems that will attempt to warm up the vehicle battery as well (up to roughly 8 kw). Both of these functions combined can require upwards of 8-10kw of total power for 30 minutes or longer to get an EV into optimal driving conditions. For many vehicles, this means an initial usage of 6-12% or more of their battery SOC before the driver even gets into their car. Even if the car is not preconditioned for the drive, this warming isn't avoided as the vehicle will just do this conditioning during the first several minutes of the drive. This loss is definitely included in many of the drives in the dataset included in the above study. But the good news here is that for the majority of EV drivers, this loss is completely avoidable, or at least, can be minimized. Here are the ways that an EV owner can almost eliminate this impact to their range
Park in a garage if possible, or in an area that gets full sun to keep the vehicle as warm as possible on cold days. Even if the temperature differences are minimal, every little bit helps reduce the loss.
ABC - Always be Charging, if possible, always plug in your car. Many EVs can be programmed or remotely warmed up via an APP, and they will pull the energy they need from the charger and not the battery if it can deliver the requested power and will only rely on battery energy if needed. This not only reduces this impact to your winter range, but it also reduces the number of charge/discharge cycles on your battery, increasing longevity by reducing degradation of your battery.
Install a L2 Charger - a Level 1 charger can deliver at most,1.8 kw from a 16 AMP L1 charger and only 1.4 kw from 12 AMP. This is just not enough energy to get an EV warm in cold weather. Time for an upgrade!
Real-World Example - My daily commute uses 5% of my battery for the drive, sometime 6% in cold weather (preconditioned, but more HVAC draw). If my car needs 5% of the battery SOC just to warm everything up for this drive, my actual range just went to 50% of the warm weather case range. Then my car sits at work all day and I must repeat this warmup process (although typically warmer in the afternoon). No charger at work, so I will lose as much as 5% in the afternoon AGAIN. But I can keep my total, out of the battery usage for a daily commute to 15% rather than 20% just by warming up from the wall outlet at home every morning.
Preconditioning for DCFC - This one is a huge variable as not every EV on the market even has this capability. If you are an EV driver and you frequently experience cold weather conditions, you WANT this in your vehicle if you want your roadtrips to be uneventful and your charging stops to be fast. On a recent road trip in temps in the low 20's, my vehicle used 3-6% of the battery to prepare the battery to accept maximum charge rates (I hit 250 kw every time). Not only is this very healthy for the battery to be at optimal temps to receive a charge, but it makes the road trips amazing in cold weather. In my experience, this might add an extra charging stop, or increase the duration of each stop by upwards of 5 minutes, but it is well worth it. On this same road trip, we made an unplanned stop (no preconditioning) but had a chance to plug in the car. We maxed out at 50 kw... 5 times slower than a preconditioned vehicle. I'll speak for Tesla, but I am guessing most vehicles have such amazing trip management software, that the vehicles are smart enough to prioritize reserving energy to make sure you arrive at your destination and will reduce preconditioning if needed.
Note, don't make the mistake that many in Chicago made this week. Many EV owners/renters, who are UBER or LYFT drivers decided to finish their day the night before with a low SOC with a plan to go first thing the next morning to the nearest Supercharger. This is what you should NEVER do. If you are reliant on DCFC charging, it is always best to FINISH your day by charging your car up while the battery is warm from usage, and for vehicles with preconditioning, will have a chance to warm it up further. Unfortunately, they chose to return their homes with a low SOC and let their cars cold soak all night. Then, first thing in the AM, these cold soaked batteries (cars that sat in below 0F temps overnight) either didn't have enough time to warm up before arrival at the Supercharger or didn't have enough power to deliver the warming effect, or both. And then, when these owners showed up at the chargers with no true understanding of their vehicle and how it charges, the owners completely panicked when the car was only pulling 5-10 kw of power for 30 minutes or longer before it was warm enough to pull "real" charging levels.
Cabin Temperature - Many EV drivers erroneously believe that their EV HVAC system is a significant cause of their winter range reduction. Actual temperatures and HVAC design (Heat pump or not) are the primary drivers here, but in my testing with my Model Y (heat pump equipped) and temps in the 20's, the HVAC pulls up to 2 kw of power during warm-up and only 0.5 to 1 kw during steady state. For most driving situations, this is a big "who cares". For road trips at typical highway speeds, this means as much as a 5% reduction in range at most. A big giant NOTHING burger, but OK, if you must reduce this impact because your are nuts... Ways to reduce this impact:
Use Seat Warmers / Reduce Cabin Temp - The testing I have done shows that the Seat warmers can use about 10%-50% of the power needed by the HVAC. Turn the seat warmer up and the cabin temperatures down to conserve energy. (Note, for me, my personal comfort is more important, so I don't do this...and, as noted, the impact to the actual road trip is so minimal, I am not sure why anyone would chose to be cold over like a couple extra minutes here or there at a charger).
Air Density - Many people don't think about this, but at sea level, at consistent air pressure values, the density of air at 0 F is 15% higher than the density of air at 90F. This density increase directly correlates to the aerodynamic drag on the vehicle and results in as much as 15% increase in energy consumption in worst cases. The reality though is that this is mostly not even noticeable when going from 70F down to 30F. All the other factors at play are more impactful so no one ever thinks about it. It also isn't unique to EVs as all vehicles experience the same thing.
Winter Tires + Misc - Many people in cold weather climates put winter tires on their vehicles to improve traction. Many also have a second set of dedicated winter rims for their vehicle for those tires. These combinations almost always result in a reduction in range for your EV. For my particular rim/tire combination, the impact has been minimal. Hard to measure when it is almost unnoticeable, but I have estimated it to be only be about 1-3% at most. Also, the aerodynamics of an EV is impacted by the snow and ice that sticks to your vehicle in winter weather.
Cold Weather and Real-World Impacts to EV Owners
So, after laying out all the sources of increased energy draw on an EVs battery, I am here to tell you that cold weather reduction in range just doesn't matter. It just doesn't, particularly if you are an intelligent EV driver, you primarily do local drives around home, and you have home Level 2 charging available to you at home or work. For most of us, the biggest impact is getting into the habit of plugging in the car every night (which honestly, we should do anyway) vs. only charging up a few times a week.
What about roadtrips Marc? Many won't believe me, because the media wants you to believe that it is the end of the world for EVs and they just become such a pain in the ass in cold weather to road trip in, that people really shouldn't even try. The reality for most EV owners is the exact opposite. For those of us that own EVs with preconditioning, the impact of cold weather on our roadtrips is so minimal. For those with EVs that do not have preconditioning, shame on you for even trying. You purchased a cheaper EV that lacks capabilities that are absolutely required for roadtripping in cold conditions and you just shouldn't try. You should know better, you are giving EVs a bad name, and you get what you paid for. Just stop it. Be better.
For those of us that made the correct purchasing decision. Here is my assessment of roadtripping an EV in the COLD. My assessment might eventually change, but for right now, fast charging stations are easy to find along all the major highways on the east coast, but they are not at every travel plaza, rest stop, or exit like Gas Stations. They are spread out on major corridors today once every 40-50 miles which means that you cannot today, just keep driving until you get down to 10% then just pull off at the next exit to charge. When you have a charging opportunity, sometimes you just have to take it. At least at the first charging stop on a road trip, this means you might be starting a charge at 35% or more just because you aren't sure you have enough range to make the next charger down the road.
For example, my trip from Home back to my hometown is a 255 mile drive with a good bit of elevation change on the last half of the drive. Because of elevation changes, I get 175 miles of range at best for this drive on good days. Not counting the 1 or 2 charging location near home and the one not far from my destination, there are a total of 4 chargers that I would typically consider (Carlisle - too close to home, Newburg - new site and good stop, Breezewood - avoid like the plague, Somerset travel plaza - perfect stop). But here is the catch. Because of the large spacing between these sites, having a reduced range on my EV in winter conditions is nearly irrelevant. At highway speeds, 40 miles is 20% of my battery, even less range for that 20% with elevation changes. This means that on a roadtrip, with this spacing, you will likely arrive at your first charging stop with an non-optimal SOC of somewhere around 25-40% SOC roughly because you just don't have enough to get to the next stop. This applies in Summer conditions too, but in winter conditions, this means that you would still have enough SOC to arrive at this SAME first charger on your trip, but now with less SOC than summer conditions, maybe 10-30%. Now, as you are sitting at that charging site (Newburg for us), we are planning out how much SOC we need to get to the next stop (Somerset for us). Because of cold weather conditions, I might need to leave the charger with 70% SOC rather than 60% SOC to get to this next location. So, not only am I arriving with a little less SOC at the current charger, I have to leave with a little more SOC to make the next one on the route. The impact is a little extra time at this stop for the extra charging needed, that is it. And we are not talking hours, we are talking a few of extra MINUTES. On Tuesday, when we did this trip with temperatures at or below 23 degrees, the total charging time for us at this first stop to go from 23-73% SOC was 22 minutes TOTAL (we had a chance to finish an episode of the Bear we started). It is difficult to estimate the cold weather impact at this particular stop, but two weeks ago, with temps in the mid 40's, I reached this location with 35% and only charged up to 60% in 10 minutes to get to Somerset with 8%. This week I arrived with 10% in Somerset so the impact of the cold weather at this stop was 12 minutes total.
Now, from this point forward on your trip, whether it is summer OR winter, an experienced EV traveler is going to try to arrive at the next charger with 5-10% SOC no matter what to get peak charging rates. This means that at each charging stop in the winter, the driver might need to add an extra 10-15% to the battery at each stop to overcome the extra energy usage between charges, or, as we did on this last trip, we actually charged LESS time at a stop and add additional stop to the trip. For us, we shortened our Somerset stop by about ten minutes to arrive in New Staton with <20% and spent 6 minutes there to have enough energy to drive around town while visiting family. By doing so, our charging stops gave us the opportunity ot charge at lower SOC ranges which results in the fastest charging sessions. We actually had to stop for a bathroom break anyway and this stop only took us out of the way by a minute or so.
Of course there are exceptions such as the individual that buys a Chevy Bolt that in the summer time, starting at 100%, that can get from their home to a destination (like family or a vacation spot) without having to stop at all, but arrives with 10%. Not only are they now not going to be able to do this trip without stopping to charge in the winter, their vehicle has no preconditioning, and their already slow 50kw of charging speed is going to be reduced to like 10-20kw, and honestly, their drive is going to suck and be 20-30 minutes longer at a minimum. I covered this already, they bought the wrong EV if this is how they want to use it, but to each their own.
Even in our own personal travels, there are a few destinations that we drive to that are just at the edge of the range of our EV in the best of conditions. But here is the thing. That is approaching 3 hours of continuous driving and I cannot go that long without stopping for a BIO break or just a stretch of the legs. In a 10 minute stop, I can easily add 30% to the battery which easily covers the reduced cold weather range, so the actual impact to most of our trips in cold weather is nothing other than arriving at our destination with a lower SOC than our warm weather trips.
Perfect Storm of Failures in Chicago this Week
Not helping the situation was the fiasco, pardon the pun, "The Perfect Storm" of circumstances that happened in Chicago over the past several days where many EV drivers, many of them Tesla owners, "got stranded" as a result of a number of different situations that independently wouldn't be an issue, but when combined together, caused a major issue. I won't get into all the specifics at this time as this post has already WAY TOO LONG. Kyle from Out of Spec Reviews put a full, nerd level 35 minute video describing the entire situation on YT (https://www.youtube.com/watch?v=K64HQ5ZPfdQ&t=422s) if you want the full details. Perhaps this will be the subject for my next post.
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