About 8:30 AM, my wife announced she needed to be in Murfreesboro TN, ~91 miles away for a grandson game. I had increased the SOC from 67% to 75% and it indicated 164 miles. But I had not anticipated: +20 mph, 26 F, headwind need to be there at 10:00 AM so I drove at 75 - 79 mph car had cold soaked overnight The navigation system routed us via Manchester SuperCharger bumping the distance from ~91 miles to ~118 miles and adding a 20 minute charging session. The lifetime 229 Wh/mi became 364 Wh/mi, a 59% decrease in range. We missed the game but thanks to AutoPilot navigation routing and the Manchester TN SuperCharger, we arrived in Murfreesboro. We picked up her grandkids and returned via Manchester SuperCharger. She has been working two jobs so I and AutoPilot did all of the driving. On the trip: 364 Wh/mi * 118 mi ~= 43 kWh, 86%, cold-soaked, now ~50 kWh pack aged after 60 k mi So I'm increasing my charge level to 90% during the winter. If we need to make another, unplanned, subfreezing dash into a headwind to Murfreesboro, we should be able take the shorter, direct route without having to route via a SuperCharger. Lesson's learned. Bob Wilson
I shudder to think of less sophisticated EVs facing the same weather challenge and their weaker, driver assistance software. Bob Wilson
cold soaked pack, sub freezing temps and headwinds are a triple threat to EV range and pack health. It's a shame you have to bump charge level up to 90% all winter, just in case. But I suppose I'd do the same if there was a chance I could get another surprise last minute notification for a trip beyond the cars present range.
Living in North Alabama, this will last only through March when I can return to more normal, 75% to 67% SOC. We just had a bad 'roll of the dice.' Fortunately, the Tesla compensated better than I might have. One additional thought is to schedule a departure for local sunrise every morning, just at dawn. With the car plugged it, it should warm the battery and cabin to keep everything ready to go for the rest of day. Bob Wilson
i wonder how much research is being put into batteries to hold a full charge without longevity degradation. that will be a big tech leap and extremely helpful.
I’ve never expected my car to outlive me and I’m 72. <GRINS> Bob Wilson ps. http://holyjoe.org/poetry/holmes1.htm
Already have it with LFP, but the ability still leaves them with shorter range in an EV compared to cars using the typical chemistry.
Having been a victim of the original Nissan Leaf - which advertised a 100-mile range, owners quickly discovered its range would in fact be less than ½ of that range as its traction pack quickly degraded from heat & insufficient thermal management. The issue was that the Nissan Leaf over-promised range - even under some of the best conditions. Reality was on the freeway - drivers would only get 70 - 75 miles of range. EV advertising can still be misleading, modernly. EV ranges have in some cases been extended to over 400 MILES. What this means is that in the worst conditions you can still drive 200 miles in some EV's. Obviously the long range EV is way more expensive than the chintzy ones. The good news is that each iteration gets better & better - especially with range. .
Now imagine your range if the +20F had been 0F (or -20C or -30C as many of the Canadian folks are experiencing). I've seen minus numbers in the sandhills of NC. The Canadian Toyotas dealers sell a special winterization kit not available in the states that keeps everything (block, 12v, cabin) in a hybrid charged, warm and ready with multiple heaters. App regulated.
We hit minus 15 C at our Nashville home about 13 years ago. heck - you needn't go to Canada to experience -30C. Here in the frosty winters of Montana, just 2 years ago (even before winter started!) ..... . Kalispell sets daily record low | Daily Inter Lake It wasn't even winter yet! The US record for Continental low temperature belongs to our Frosty state - if memory serves. - 70f. Point being that even with our sub-zero temperatures here, or whether you calculate it through Fahrenheit or Celsius ..... there are quite a few Tesla's running around our landscape all winter long. Fortunately most people that have to leave the house in frigid weather know what the risks are. .
ps isn't middle English such a fun language to study ! Ever count the words on a page of middle English that look familiar? 10 per page, if lucky, or a middle English scholar. I looked up chaise, than started counting how many words I couldn't place into the story without backtracking. Thank You for linking that ole poem / story.
Fun fact about the author's son. He served on the US Supreme Court longer than any other chief Justice. Crap you remember from law school. Nowadays - the word Holmes comes up more frequently as a greeting by gangsta thugs. Times change. Many elementary schools don't even teach cursive writing - ergo our daughter homeschools her four kids. My elementary school was named after one of Holmes Harvard associates - Ralph Waldo Emerson. But we digress.
BTW, this is this morning's preconditioning: 5:15 AM to 6:00 AM - initial charge at ~3.94 kW into the cold soaked battery, ~29 F. 6:00 AM to 6:20 AM - rest (?) 6:20 AM to 6:30 AM - initial charge into warmed battery. 6:30 AM to 6:55 AM - begins normal cabin warming profile 6:55 AM to 7:02 AM - a block charge to battery(?) while cabin heating continues 7:02 AM to 7:05 AM - final cabin heating taper Bob Wilson
Bob, were you already at 90% SOC and just did the preconditioning without adding any range? I wonder if you'd see similar readings if you ran preconditioning with less SOC at those kinds of temps. It doesn't look to me like you used too many kW from the grid to get the battery and cabin inhabitable, especially if you could have / might have have added some range while preconditioning.
-9 F at the loading station of Big Sky's Six Shooter ski lift last week. Other thermometers we saw varied from -4 to +5 F (excluding a 'warm' +15 in direct sunlight at the top of another lift). We were well bundled up, because we just couldn't miss getting first tracks on several runs in the fresh powder. This was much 'warmer' than our first visit to Big Sky decades ago, when the ski operations didn't even open due first to high winds (blowing over rail cars up north), then actual cold. So we nordic skied nearby, took a snowcoach tour into the Park to Old Faithful at -25 F, then left for home at -41 F. Being younger back then, we could handle a bit colder temperatures than now. Rogers Pass, January 20, 1954. Before my time, but I can still hear my mother quoting it. https://en.wikipedia.org/wiki/Rogers_Pass_(Montana)#Record-cold_temperature Not to be confused with the other Rogers Pass (British Columbia), named for the same person, but located a few hundred miles to the northwest. And also damn cold, plus avalanche-y. Coldest Temperatures Ever Measured in the Contiguous U.S. | Weather Underground
My operational scenario is to plug-in and charge at home when I arrive. Within an hour, the car is at the nominal target. However, there is some minor loss, 5-10 miles, overnight. It reported two charging sessions: 2.912 kWh and 1.858 kWh, a total of 4.77 kWh or $0.57 ($0.12/kWh.) Bob Wilson
visiting our daughter and grandkids for a week, we're staying in our timeshare - as friends are using our Nolensville house. Landed in Nashville late Friday night - only to wake up with snow on the ground. not too often one leaves Montana winters only to get colder weather in the south. Sure glad our budget rent a car Prius ended up being painted black as it really captures the heat. if you have to burn $4.12 gas, better to be getting 48 MPG than not. Oh well .... the rest of our stay well be in the 40° and 50° .... plus the pool is heated and indoors
