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Out of Spec 3 Row EV race - Lucid Gravity driven by Kyle

It doesn't have it for me on this video, probably it can't handle over 1hr length 🤣
 
eelpout said:
started to watch it. A 100% full battery and (Kyle's) Gravity is estimating only 260 mile range? I know it's cold in ME but really? :)

Edit: after driving for a while they changed from Dynamic (260) to Rated and it said around 330 miles range.
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It was well below freezing overnight when they started tho. Glad the system updated as the battery warmed, but in that kind of cold and vehicle being left outside, you will see extremely high range loss in any EV.
 
Kyle is saying the Gravity he is in was shipped with larger wheels than are actually on the car during the race. The route planner is calculating based on the larger wheels.

WTH!

Oh, and why are the Chargers letting the Cowboys stay in the game. 😊
 
Why are they running at 86MPH? That's not going to win the race as they burn more KWH, which means longer charging. I always thought around 55-60MPH is the long distance, including charging, sweet spot. Maybe faster for Gravity since it can charge so quickly, but not at 85MPH I wouldn't think.

EDIT: maybe they want to be first since number of stalls at each location is limited?
 
Smorgasbord said:
Why are they running at 86MPH? That's not going to win the race as they burn more KWH, which means longer charging. I always thought around 55-60MPH is the long distance, including charging, sweet spot. Maybe faster for Gravity since it can charge so quickly, but not at 85MPH I wouldn't think.

EDIT: maybe they want to be first since number of stalls at each location is limited?
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If you are charging at 1000mph then in a minute of charging you add 17 miles of range per minute.
Driving at 85mph versus 60mph in a 60 miles trip will save 17 minutes, and will probably only save 20 miles of range (but gain about 290 miles in that time charging).
So other than limitations due to charging stations not being every mile and each charging station causing a delay (traffic lights away from the freeway), for winning a race the optimal speed is likely well over 100mph.

Back in 2013 if you had a 60kWh model S and a 90kW supercharger then things were a little different if you had to charge over 90%. With a Gravity everything is different to that.
 
XTesla said:
If you are charging at 1000mph then in a minute of charging you add 17 miles of range per minute.
Driving at 85mph versus 60mph in a 60 miles trip will save 17 minutes, and will probably only save 20 miles of range (but gain about 290 miles in that time charging).
So other than limitations due to charging stations not being every mile and each charging station causing a delay (traffic lights away from the freeway), for winning a race the optimal speed is likely well over 100mph.

Back in 2013 if you had a 60kWh model S and a 90kW supercharger then things were a little different if you had to charge over 90%. With a Gravity everything is different to that.
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Good points, but not even Gravity charges that high for long. So I guess they have to balance charging rate with time to get to and plug in to chargers, etc.

FWIW, my first EV (which I still own) is a Tesla Roadster - and with no super charging we had lots of discussion over speeds and trying to find 70 amp L2 chargers on the road (which were up and down the CA coast at one point, but now they're all J1772s with lower amperages).
 
Smorgasbord said:
Good points, but not even Gravity charges that high for long. So I guess they have to balance charging rate with time to get to and plug in to chargers, etc.

FWIW, my first EV (which I still own) is a Tesla Roadster - and with no super charging we had lots of discussion over speeds and trying to find 70 amp L2 chargers on the road (which were up and down the CA coast at one point, but now they're all J1772s with lower amperages).
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I think Kyle points out they charged Gravity at over 300kWh for nearly 10min and were above 260kWh at 12 min, which is a much better curve than the other non-Gravity cars in the race. And it looks like they could have maintained over 250kWh for a while longer.

You’re exactly right they are balancing that high rate with how long to charge and how far they need to get to next charger. Seems like all the groups are dialed in on the balancing act.
 
The Gravity is charging at up to 1200mph (400kW) while the Escalade is charging at a max of 700mph (350kW). That means 12 minutes a charge instead of 20 minutes a charge. The Escalade may have fewer delays due to detours to charging stops, but from the above information the main gravity should win.
The supercharger-only Gravity is pretty well matched to the model X... both will limit to 250kW but the Gravity charges deeper at that charging speed, while the X seems so far to be a bit more efficient. Ultimately those two may be pretty well matched with the Escalade (depending on how many fast chargers the Escalade can find it can probably finish second behind the primary Gravity). The R1S will likely be a bit behind those with inefficiency and not the fastest charging.

Range wins the first few hours, but ultimately it is charging speed in mph (with range as the tiebreaker) is the deciding factor.
 
Smorgasbord said:
Why are they running at 86MPH? That's not going to win the race as they burn more KWH, which means longer charging. I always thought around 55-60MPH is the long distance, including charging, sweet spot. Maybe faster for Gravity since it can charge so quickly, but not at 85MPH I wouldn't think.
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86 is right in the sweet spot or actually a little low for the Gravity. Most likely they are setting ideal speed based on the chargers they are trying to hop between.

I’d be targeting charging between roughly 5% (or lower if you believe the BMS) and 60%. That takes 14 minutes on a 400 kW charger and gives you about 68 kWh. How far that 68 KW will carry you depends on speed, but in good weather it’s maybe 232 miles at 70 (based on State of Charge’s recent test), 264 at 60 or just 185 at 85 mph. But including the charging stop time plus 5 minutes to get on/ off the freeway that average rate you’re coving ground is 56 mph for the 60 mph cruse setting, 64 mph for 70 and 74 for 85. So faster is better with a car that charges this fast.

Of course this assumes perfectly placed charging stations. Since you don’t have that luxury you dial speed up or down to arrive at your closest option at 5% charge regardless of distance. This math can easily have you over 90, but them cops become the limiting factor.
 
XTesla said:
The Gravity is charging at up to 1200mph (400kW) while the Escalade is charging at a max of 700mph (350kW). That means 12 minutes a charge instead of 20 minutes a charge. The Escalade may have fewer delays due to detours to charging stops, but from the above information the main gravity should win.
The supercharger-only Gravity is pretty well matched to the model X... both will limit to 250kW but the Gravity charges deeper at that charging speed, while the X seems so far to be a bit more efficient. Ultimately those two may be pretty well matched with the Escalade (depending on how many fast chargers the Escalade can find it can probably finish second behind the primary Gravity). The R1S will likely be a bit behind those with inefficiency and not the fastest charging.

Range wins the first few hours, but ultimately it is charging speed in mph (with range as the tiebreaker) is the deciding factor.
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Have to factor in churn time too though... getting on/off the highway, getting to/from the station, sometimes messy charger initiation, shared/derated power, etc. That churn is minutes (sometimes many minutes) per stop just getting off the highway. If the longest range vehicle can do fewer stops, it might save a half hour or more in wasted churn time during the whole trip.

I'd give the Escalade the edge. But Kyle is a demon on these races so it's probably a tossup.
 
dbsb3233 said:
Have to factor in churn time too though... getting on/off the highway, getting to/from the station, sometimes messy charger initiation, shared/derated power, etc. That churn is minutes (sometimes many minutes) per stop just getting off the highway. If the longest range vehicle can do fewer stops, it might save a half hour or more in wasted churn time during the whole trip.

I'd give the Escalade the edge. But Kyle is a demon on these races so it's probably a tossup.
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Yea I added 5 minutes for “churn”, but I agree it’s highly variable if you’re not using superchargers and don’t know the individual locations. But even if you increase it to 10 minutes the optimization is up around 100 mph for a car that charges this fast. Not enough that those speeds make actual sense though; you probably need to add some probability that your race is simply lost at every charger, especially if you’re using EA, etc.
 
PetevB said:
Yea I added 5 minutes for “churn”, but I agree it’s highly variable if you’re not using superchargers and don’t know the individual locations. But even if you increase it to 10 minutes the optimization is up around 100 mph for a car that charges this fast. Not enough that those speeds make actual sense though; you probably need to add some probability that your race is simply lost at every charger, especially if you’re using EA, etc.
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Yeah, it really depends on so many factors. Like the Escalade leaving the first charger within only 47% (IIRC). They're giving up much of their range advantage by leaving the station that soon, thus requiring more total charges. If they keep doing that, they'll turn it into more of a charging speed contest and cede the advantage to the Gravity. As long as I'm still getting like 150kW+, I'm probably staying to take the sure thing so I can stay on the road longer rather than gambling on the next station having peak power, no red lights, no traffic, etc.

The best charge is always the one you don't even get off the highway to do because you've got the long range to skip it.

They get so antsy on these races they talk themselves into leaving stations way early assuming a perfect, low-churn next stop that usually doesn't work out that way. A 5 minute charge that took 6 minutes to get on/off the highway and another minute to start is worth less than half what they're counting it as. That's really a 12-minute stop.
 
dbsb3233 said:
Yeah, it really depends on so many factors. Like the Escalade leaving the first charger within only 47% (IIRC). They're giving up much of their range advantage by leaving the station that soon, thus requiring more total charges.
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They're playing the charge curve game. While they've got a big battery, charging slows down as the SOC rises, so it can pay to stop charging, get on the road and drive until the SOC is really low, then start a charge at a much higher rate. I'm not saying I agree, just that's what they're doing.

The Gravitys have an advantage that the charge curve is really aggressive early on, and then only slowly tapers. For instance, 10% to 80% takes under half an hour at Tesla 350kW chargers, but it'll take another half hour to get that last 20%, so it isn't worth it. Tom on the Gravity SC-only team has charge curve graphs with him and so they're playing that game as well since Kyle's Gravity can charge at 400kW EA/EVGo/Mercedes chargers.

I do have YT premium (splitting among a bunch of family members on the family plan makes it worthwhile), so I'm really enjoying this format. It was interesting to watch Kyle beat himself up over not spotting a high power charger on the route (because it was mis-typed in PlugShare I think) and so they stayed too long at their previous charger. But, as he kept talking he was talking single digit minutes - that's how close they think this race will be.

I do agree that the stop churn is also an issue to be considered. The Model X team was complaining about 3 traffic lights between them and one of their stops. I'm sure there's a formula that could be encapsulated even in an Excel spreadsheet to work out best charging strategies, but these are car guys, not computer geeks.
 
Smorgasbord said:
They're playing the charge curve game. While they've got a big battery, charging slows down as the SOC rises, so it can pay to stop charging, get on the road and drive until the SOC is really low, then start a charge at a much higher rate. I'm not saying I agree, just that's what they're doing.

The Gravitys have an advantage that the charge curve is really aggressive early on, and then only slowly tapers. For instance, 10% to 80% takes under half an hour at Tesla 350kW chargers, but it'll take another half hour to get that last 20%, so it isn't worth it. Tom on the Gravity SC-only team has charge curve graphs with him and so they're playing that game as well since Kyle's Gravity can charge at 400kW EA/EVGo/Mercedes chargers.

I do have YT premium (splitting among a bunch of family members on the family plan makes it worthwhile), so I'm really enjoying this format. It was interesting to watch Kyle beat himself up over not spotting a high power charger on the route (because it was mis-typed in PlugShare I think) and so they stayed too long at their previous charger. But, as he kept talking he was talking single digit minutes - that's how close they think this race will be.

I do agree that the stop churn is also an issue to be considered. The Model X team was complaining about 3 traffic lights between them and one of their stops. I'm sure there's a formula that could be encapsulated even in an Excel spreadsheet to work out best charging strategies, but these are car guys, not computer geeks.
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Yeah that's the well-known theory (that it's better to leave early & charge more often (ABC) in order to charge in the highest kW part of the charge curve). That's what ABRP tells people to do, and what most native route planners in EVs tell people to do, and what many EV purists say is the "right" way to do it - only charge barely enough to get to the next station with very little room for error. In theory, that is faster if everything were ideal (perfect charging at the bottom of the offramp).

In practice, however, it's rarely ideal or perfect. (1) They tend to forget/undercount the added travel time getting off the highway to DCFC stations, and (2) DCFC is still often messy. Full stations, broken chargers, derated chargers, power sharing, moving over to the next charger, cold batteries, slow payment activations, charge faults, etc. The extra 5-10 minutes (more if messy) quickly negates the advantage gained from a few minutes of higher kW.

These guys tend to chase the "perfect", then get reminded that the reality of DCFC charging is rarely perfect. Makes for an entertaining video (all the "oops"s.) But the better approach is often to expect the imperfect, not the perfect. Thus why I lean toward charging deeper if a current session is still getting good power (even though it's not peak power early in the curve). A bird in the hand, and all that (within reason).

Also, these guys usually find themselves having to slow down (losing time) every other leg in order to make it to the next charger because they left the last charger too soon. Again, chasing the "perfect" but then getting reminded that things rarely go as perfectly as they assume.
 
dbsb3233 said:
Yeah that's the well-known theory (that it's better to leave early & charge more often (ABC) in order to charge in the highest kW part of the charge curve). That's what ABRP tells people to do, and what most native route planners in EVs tell people to do, and what many EV purists say is the "right" way to do it - only charge barely enough to get to the next station with very little room for error. In theory, that is faster if everything were ideal (perfect charging at the bottom of the offramp).

In practice, however, it's rarely ideal or perfect. (1) They tend to forget/undercount the added travel time getting off the highway to DCFC stations, and (2) DCFC is still often messy. Full stations, broken chargers, derated chargers, power sharing, moving over to the next charger, cold batteries, slow payment activations, charge faults, etc. The extra 5-10 minutes (more if messy) quickly negates the advantage gained from a few minutes of higher kW.

These guys tend to chase the "perfect", then get reminded that the reality of DCFC charging is rarely perfect. Makes for an entertaining video (all the "oops"s.) But the better approach is often to expect the imperfect, not the perfect. Thus why I lean toward charging deeper if a current session is still getting good power (even though it's not peak power early in the curve). A bird in the hand, and all that (within reason).

Also, these guys usually find themselves having to slow down (losing time) every other leg in order to make it to the next charger because they left the last charger too soon. Again, chasing the "perfect" but then getting reminded that things rarely go as perfectly as they assume.
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I have seen Ryan do what I would suggest is a hybrid approach, which is just 'overcharge' 5% or so each stop. This buffer doesn't take much time, but gives extra range for maintaining speed, countering stopping and charge handshake/off-ramps, and after 3-4 stops actually adds up to skipping a charge stop entirely.
 
illopp00 said:
I have seen Ryan do what I would suggest is a hybrid approach, which is just 'overcharge' 5% or so each stop. This buffer doesn't take much time, but gives extra range for maintaining speed, countering stopping and charge handshake/off-ramps, and after 3-4 stops actually adds up to skipping a charge stop entirely.
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Yep. I'd go even higher in most cases, but even 5% more than the planner says is good.

Personally, we usually just DCFC to around 80% most DCFC stops on road trips. In our Mach-E, that's where it hit the cliff and fell way off, so it made sense to stop there. Staying till 80% makes it closer to a stress-free ICE-like driving experience. We lose about 3-4 minutes in charging time living in the 30-80% range rather than the 10-60% the planers recommend, but that 3-4 minutes is worth it in safety, peace of mind, and more flexbility. Allows us to go one station further many times, or at least keep a backup station in range just in case.

Depends on the EV though. In our Macan, it usually stays above 100kW+ until 85%, so we often stick around till then. Haven't DCFC'd the Gravity yet, but we'll figure out the extended sweet spot on it too. But I'd rarely leave a DCFC at just 47% if I were still getting good power, unless it's the final DCFC of the day and I have cheaper L2 at the destination. Or if it were a super expensive DCFC I was desperate to stop at.

Of course, the main advantage of a 450 mile EV is super long range so that you DON'T have to DCFC many times. Our frequent 785 mile Denver-Vegas drive needed 5 DCFCs in the Mach-E. In our Macan it's 3-4. In the Gravity I think I'll be able to do it in just 2.
 
Remember, these guys are racing, so they’re going to make different choices than people on vacation or a business trip.

And between the two Geavitys especially, a few minutes of charging may be all that separates them at the finish line.
 
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