Eastern Canada Superchargers

[rapoport3a]

I'll bring the topic back in by saying that because there are Superchargers along so much of I-90, a set in SW Ontario is *badly* needed and should be put in right after Kingston --- not that one has anything to do with the other.

I wonder whether the squeaky wheel gets the grease (!) and some kind of direct but polite campaign would get faster results. After all, many Americans travel between upstate NY and the midwest along QEW -- 403 -- 401.

 

[sitter_k]

I hope my finances allow me to buy a 85D soon and put a hpwc on my property just off the hi way in Belleville. Better yet, Hopefully Coburg/Trenton sc come online before that.

 

[Doug_G]

I think that's a bit pessimistic - I managed 400 km with 40 km range shown as remaining during the summer Ottawa-Toronto, and for most of the trip I was doing 100 km/h

I would not start with optimistic assumptions, even if you had previously done the trip. Weather has a big impact; not just temperature, but wind as well. I've noticed a systematic difference going East versus West, and believe that is due to the prevailing winds. A headwind can really burn energy; likewise a tailwind can help. Elevation changes are also important (fortunately Ontario is relatively flat). Simply driving in line with some trucks can result in some drafting effect. Range can be affected by rain and snow - especially rain if you're effectively driving through puddles. I've seen impacts of 30% in driving rain.

Mileage can and will vary!

Again, I can't emphasize this enough, those who haven't driven in winter yet should be aware of the potentially dramatic impact of low temperatures. If you keep driving like you did in the summer you're going to get a surprise.

I'll bring the topic back in by saying that because there are Superchargers along so much of I-90, a set in SW Ontario is *badly* needed and should be put in right after Kingston --- not that one has anything to do with the other.

In addition to Drummondville and Kingston, we've got Comber, Woodstock, and Barrie coming soon, I'm told. People might want to keep their eyes out for permitting and/or ground breaking.

 

[mknox]

Again, I can't emphasize this enough, those who haven't driven in winter yet should be aware of the potentially dramatic impact of low temperatures. If you keep driving like you did in the summer you're going to get a surprise.

I ended up learning this "the easy way". I got my car when it was still wintery in 2013 and was blown away by how much better my range got when the weather warmed up in the summer. I was prepared for the winter of 2013/2014 as a result.

 

[PoweredByRain]

I ended up learning this "the easy way". I got my car when it was still wintery in 2013 and was blown away by how much better my range got when the weather warmed up in the summer. I was prepared for the winter of 2013/2014 as a result.

Good planning.

Hey, even in Victoria I see a huge difference between winter and summer. Yes, there is a winter in Victoria.

Doug: yes, no doubt headwinds vs tailwinds makes a big difference. You can see a 120 km/h airspeed doing 100 km/h with a 20 km/h headwind, and 20 km/h isn't a huge wind. Alas, there is no airspeed sensor on the car. That would actually be a very cool thing to have.

This is actually funny to think about as a pilot; when flying you travel at whatever airspeed you had planned, so if there's a headwind it's obvious because it took you longer to get to your destination. Same power, longer time = more energy. When driving you travel at whatever ground speed you had planned, so the time to destination (ignoring things like traffic) doesn't change. But you may have just spent that time at a significantly higher power due to going a higher airspeed, if facing a headwind.

 

[Cottonwood]

This is actually funny to think about as a pilot; when flying you travel at whatever airspeed you had planned, so if there's a headwind it's obvious because it took you longer to get to your destination. Same power, longer time = more energy. When driving you travel at whatever ground speed you had planned, so the time to destination (ignoring things like traffic) doesn't change. But you may have just spent that time at a significantly higher power due to going a higher airspeed, if facing a headwind.

Yup, and energy/mile(km) used to overcome aerodynamic drag goes up as the square of airspeed; the power required goes up as the cube of airspeed, but you get there faster.

As the physicists say, wind is a non-conservative force, but as a pilot, a bicyclist, and a Tesla driver, "Wind is a four-letter word!"

 

[Doug_G]

Exactly. If you think about it, wind is much worse than driving fast.

If you speed up from 100 kph to 120 kph, the impact on your range is only square-law. That's because with the increased speed, you go further in the same amount of time. So the cube-law aerodynamic impact is reduced to square-law impact on range.

If you drive at 100 kph into a 20 kph headwind, the additional impact on your range is cube-law. You're not going any faster, so you're just using more energy to go the same distance in the same amount of time.

 

[KenN]

Ummmmmm ... I'm not sure I agree with that.

 

[Doug_G]

Well, it's a first-order approximation. Doesn't take into account ground effect under the car.

 

[mrElbe]

How would "breaking wind" affect the equation? :smile:

 

[RichardC]

Good planning.

This is actually funny to think about as a pilot; when flying you travel at whatever airspeed you had planned, so if there's a headwind it's obvious because it took you longer to get to your destination. Same power, longer time = more energy. When driving you travel at whatever ground speed you had planned, so the time to destination (ignoring things like traffic) doesn't change. But you may have just spent that time at a significantly higher power due to going a higher airspeed, if facing a headwind.

As another pilot, bicyclist and Tesla owner, I agree that headwinds are a pain, but much less so in the Tesla than in a plane (where the "road" is physically moving backward). I believe that the range reduction effect on the Tesla is simply the same as the reduction that would result from driving at the higher speed. For example, the range at 80 km/hr into a 20 km/hr headwind would be the same as driving at 100 km/hr (but you are covering less ground each hour).

I have been pleasantly surprised by the relative lack of impact on range of temperatures in the high single digits (i.e., 6 to 8 degrees C) and have the following observations after travelling to Montreal and back earlier this week (charging only at the Superchargers).

In preparation, I cleaned the car (to marginally reduce wind resistance), slightly increased tire pressure (but still well below the rated maximum pressure), set the ride height to drop at 80 km/hr and pre-heated the car while charging.

The trip east was during daylight and no rain. The car was set to display Ideal Range and the next Supercharger was set as the destination on the Navigation System. The difference between the Ideal Range and the Distance to Destination (Supercharger) is the "Reserve" that you have to manage with your speed and power consumption. Leaving the Lawrence Avenue Supercharger I had an Ideal Range of 456 km and a Distance to Destination of 420 km, thus providing a notional Reserve of 36 km. I had identified (with the assistance of Doug_G, Plug-Share and others) a number of charging stations that could be used for a top-up, if required. The traffic was slow at first, with the result that the Reserve actually increased to 46 km and gave me the margin to increase the speed. I was periodically checking the Reserve and Distance to Destination to make certain that the Reserve was not being consumed at a disproportionate rate (i.e., that more than 75% of the Reserve remained after 105 km, that more than 50% of the Reserve remained after 210 km, and more than 25% of the Reserve remained after 315 km). I also kept an eye on the average power consumption which was around 171 Whr/km. During the first part of the trip I found that an average of 100 km/hr was leaving a substantial Reserve and increased the speed to 105 km/hr for the latter part for an average of around 103 km/hr, and arrived at the Cornwall Supercharger with 8 km of range left. The temperature was generally around 7 degrees C. It was completely clear to me, after the first 50 or 100 km, that the Cornwall Supercharger was within range. While the seat heater was used, there was no need for heat or defrost.

The trip back was more challenging as it was at night, there was light rain falling for a significant part of the trip, and heating and windshield defrosting were used as required. On the positive side of the ledger, there were a number of 80 km/hr construction zones which helped to reduce power consumption. Much to my surprise the Reserve measure again held up with the result that speed increased toward the end for an average of around 97 or 98 km/hr (with 8 km of range left at the Toronto Supercharger).

In each case I started out relatively slowly and sped up once it was clear that the rate of power consumption was going to permit the next Supercharger to be reached without any need for further charging.

 

[Doug_G]

In each case I started out relatively slowly and sped up once it was clear that the rate of power consumption was going to permit the next Supercharger to be reached without any need for further charging.

Yes, that is "best practice". That's how I always drive - cautious at first, then increasing speed (or occasionally cabin heat!) when it becomes obvious that I am going to arrive with sufficient safety margin.

There is one thing I will caution about: coming in to charging stations with single digit range remaining. I've noticed that a lot of people do this. I've always maintained a minimum 30 km safety buffer, and it's served me well. Every once in a while you hit an unexpected detour - road closure, accident, GPS navigation error, whatever - that results in you traveling more distance than you expected. I've had it happen more than once.

Once while driving my Roadster, my GPS told me to exit the highway where there was nothing but a concrete wall. The map was wrong. By the time I recovered from that I had gone an extra 15 km.

I've met people who have run out of power in the middle of the night with their young family in the car. Don't be that guy!

 

[PoweredByRain]

RichardC: that is awesome, that's the same thing that I've done, though I like to have way more of a reserve than 8 km at the end. I like to have a reserve on top of the reserve. But then, the one time I had to do this, it was the middle of the night, in mountainous terrain I had never traveled over before!

Doug_G: that doesn't make any sense to me. Rolling resistance is proportional to ground speed. So going faster over the ground incurs more losses, regardless of the wind. But the portion of drag due to airflow, which I believe is dominant at 100 km/h, is proportional to the square of the airspeed. There is no "airspeed due to ground speed versus airspeed due to wind" effect, except perhaps some very small difference affecting just the portion of the air affected by the road. (I doubt this effect is significant, but I would of course be prepared to accept experimental evidence!)

- - - Updated - - -

There is one thing I will caution about: coming in to charging stations with single digit range remaining. I've noticed that a lot of people do this. I've always maintained a minimum 30 km safety buffer, and it's served me well. Every once in a while you hit an unexpected detour - road closure, accident, GPS navigation error, whatever - that results in you traveling more distance than you expected.

Or even an accident on the highway, which forces you to be stopped for some time. Unless you have zero need for climate control, that's going to eat into your buffer pretty quickly. Traveling very slow speeds is also less efficient, so a couple of km of 0-10 km/h could really ruin your day.

 

[RichardC]

Yes, that is "best practice". That's how I always drive - cautious at first, then increasing speed (or occasionally cabin heat!) when it becomes obvious that I am going to arrive with sufficient safety margin.

There is one thing I will caution about: coming in to charging stations with single digit range remaining. I've noticed that a lot of people do this. I've always maintained a minimum 30 km safety buffer, and it's served me well. Every once in a while you hit an unexpected detour - road closure, accident, GPS navigation error, whatever - that results in you traveling more distance than you expected. I've had it happen more than once.

Doug,

I agree with you and would recommend that you carry much more reserve, especially if you are unfamiliar with the geography, have any uncertainty about the weather, don't have an alternative (lower power consumption) detour route and don't have multiple charging options at the destination. It also helps to be very familiar with your Model S and the roads and charging alternatives in the area. In this case, the terrain was relatively flat and the road familiar, the weather was stable and well above freezing, the road (the 401) was clearly open and moving well (as reflected in real time on Google Maps), there were alternative (lower power consumption) routes to the Supercharger (Hwy 2 in the case of Cornwall, and Kingston Road to Lawrence, or Ellesmere, or Shepherd, in the case of the Toronto), and there were a number of lower power charging alternatives in the vicinity of each Supercharger. I have also done enough long road trips with the Tesla over the past 22 months to have a reasonable degree of experience with its power consumption (and what can be done to further reduce power consumption if needed). While I have never taken the car below 8 km of range, I am aware that there is a small buffer of a few further km's below 0 km (and of the warning signs that it is running out).

Under all of those circumstances, and as something of a test, I wanted to see what type of average speed was possible between the Toronto and Cornwall Superchargers, and would have pulled off around Kingston if the car wasn't able to sustain (at safe speeds) at least a 30 km reserve for the trip. In each case, I actually built up an increased reserve at the beginning of the trip to confirm that I could easily slow down a bit and increase the reserve (or pull off and top up at a level 2 charger) if required along the way. I would also note that I was travelling solo, such that no one else would have been inconvenienced, in the worst case, if I had to stop at a hotel for an overnight low power charge.

All of that being said, I would agree with your recommendation and will not in fact make the same trip again. The delays associated with range charging at the Superchargers (which seem to take forever), the fact that the weather is getting colder (which seriously increases power consumption and reduces range), and the hope and expectation that the Kingston Supercharger will arrive reasonably soon, means that this was an experiment which was instructive but that I, for one, do not plan to repeat.

As a final observation, I note that there were a number of trucks which were averaging around 95 km/h and could permit a Model S owner to make the trip at a slightly lower average speed while maintaining a 30+ km range buffer by drafting at a safe distance. I followed one for a while on the west-bound trip but prefer to drive with a much larger buffer of open road and visibility (and have been spoilt by other cars which have radar cruise control which allow you to manage the following distance automatically). I also find that increasing the speed a bit to avoid regen on the downhill stretches and reducing it again on the following uphill sections helps to save power but takes more work than setting a speed and letting the cruise control do its thing.

I am looking forward the Kingston Supercharger making these concerns and strategies largely a thing of the past!

- - - Updated - - -

I note that the permitting of Kingston has been add to:

http://supercharge.info/

 

[PoweredByRain]

The delays associated with range charging at the Superchargers (which seem to take forever),

Seems. It's actually still faster than most Level 2 chargers, right up to the end. I remember thinking how much it had slowed down when the taper reached 40 kW, then thinking "wait a second, most public chargers are 6 kW".

I also find that increasing the speed a bit to avoid regen on the downhill stretches and reducing it again on the following uphill sections helps to save power

I agree! I have come across some who disagree, but I figure:
- regenerative braking may be efficient but it isn't 100% efficient, and
- the time spent at a lower speed is actually longer than that spent at a higher speed (usually),
so the net result should be as you state: it's actually (slightly) better to allow speed to vary according to terrain.

Within reason, of course. And practically speaking, leaving the cruise control on and allowing regen doesn't incur that big a penalty, so unless you're trying to stretch range it's not a bad idea to just let the cruise control do its thing. The Model S cruise control is actually pretty cool, keeping to within 1 km/h using just regen.

 

[RichardC]

Seems. It's actually still faster than most Level 2 chargers, right up to the end. I remember thinking how much it had slowed down when the taper reached 40 kW, then thinking "wait a second, most public chargers are 6 kW".



I agree! I have come across some who disagree, but I figure:
- regenerative braking may be efficient but it isn't 100% efficient, and
- the time spent at a lower speed is actually longer than that spent at a higher speed (usually),
so the net result should be as you state: it's actually (slightly) better to allow speed to vary according to terrain.

Within reason, of course. And practically speaking, leaving the cruise control on and allowing regen doesn't incur that big a penalty, so unless you're trying to stretch range it's not a bad idea to just let the cruise control do its thing. The Model S cruise control is actually pretty cool, keeping to within 1 km/h using just regen.

When it comes to charging speeds everything is relative.

While the range charge at the Supercharger is mostly faster than a Level II charger, I have never waited for a Level II charger to finish a charge. At home there is no delay, because the charging is complete by the next morning, and on the road I have only ever used a level II charger overnight, again where the car is fully charged by the next morning. While part of this is clearly subjective, when you are ready to go and the car is not, the wait seems interminable.

I agree that adjusting the speed to avoid regen achieves only quite modest energy savings, and is limited to circumstances, such as the 401, where the hills are limited and the slopes quite modest. In such circumstances the adjustments are typically similar to the changes in speed made by loaded trucks, such that if you are trying to stretch the car's range that the strategy will help keep you in the right lane whereas the cruise control at the same average speed will have you passing the trucks going uphill and have them passing you on the downhill sections.

 

[Doug_G]

Seems. It's actually still faster than most Level 2 chargers, right up to the end. I remember thinking how much it had slowed down when the taper reached 40 kW, then thinking "wait a second, most public chargers are 6 kW".

And none of them are more than 20 kW. It's still faster than anything else. That said, the idea of Superchargers is supposed to be that you don't have to wait for 100% in order to get to the next one.

Kingston-Toronto is a bit too far for you to maintain fast 401 driving speeds in extreme winter conditions. My rule of thumb for minimizing travel time is, "don't drive faster than you can charge." 40 kW charging is about 185 kph, so it's best to wait for the range charge rather than driving slower. If you get below 20 kW then you might as well unplug and get on the road.

it's actually (slightly) better to allow speed to vary according to terrain.

There was a long and exhaustive thread where this was discussed in great detail, and in the end everyone agreed with that conclusion. It is always better to "coast" rather than regen. Of course in some situations the difference is very small. (Of course if you really need to slow down, it's always better to use regen than your friction brakes.)

That said, I expect you will gain more by drafting, even at a very safe distance from the truck.

While the range charge at the Supercharger is mostly faster than a Level II charger, I have never waited for a Level II charger to finish a charge. At home there is no delay, because the charging is complete by the next morning, and on the road I have only ever used a level II charger overnight, again where the car is fully charged by the next morning. While part of this is clearly subjective, when you are ready to go and the car is not, the wait seems interminable.

My policy is to range charge overnight, and not when I'm waiting for it. Especially on Level II - it's always better to just get on the road and drive a little slower... you still arrive faster. (That will change with Superchargers - I'll wait if I really need it.)

I agree that adjusting the speed to avoid regen achieves only quite modest energy savings, and is limited to circumstances, such as the 401, where the hills are limited and the slopes quite modest. In such circumstances the adjustments are typically similar to the changes in speed made by loaded trucks, such that if you are trying to stretch the car's range that the strategy will help keep you in the right lane whereas the cruise control at the same average speed will have you passing the trucks going uphill and have them passing you on the downhill sections.

The optimum strategy for range is to get behind a truck and maintain a safe distance, no matter what the incline.

I really do miss adaptive cruise control; if there ever was a car that needed it, it's the Model S.

 

[PoweredByRain]

I really do miss adaptive cruise control; if there ever was a car that needed it, it's the Model S.

Ah, well, newer models will have this. The sensors are now included in the car.

If only there weren't such a huge financial hit to upgrade, I'd have ordered a P85D.

(Instead I think I'll wait four or five years, at which point the battery packs will be bigger capacity and hopefully lighter too.)

- - - Updated - - -

While the range charge at the Supercharger is mostly faster than a Level II charger, I have never waited for a Level II charger to finish a charge. At home there is no delay, because the charging is complete by the next morning, and on the road I have only ever used a level II charger overnight, again where the car is fully charged by the next morning. While part of this is clearly subjective, when you are ready to go and the car is not, the wait seems interminable.

Ah, yes, that makes perfect sense. I'm a bit of a cheapskate (aka excellent economiser) and have at times waited at public charging stations. I have a backlog of podcasts I'm catching up on.

 

[DRK]

Had my car in at Service in Toronto and they mentioned that the Barrie location would be on-line in 2 months!

 

[Doug_G]

I've heard similar things, but we have to take it with a grain of salt. Usually Tesla doesn't announce a Supercharger opening until they're sure of the date, and that is usually a matter of days before it opens.