Is anyone else having trouble deciding between 40kWh and 60kWh?

[santana338]

From my perspective, the 40kWh battery is the right choice. I am going with some of the upgrades to keep the cost down on what will essentially be a daily commuter car. We have a family car that we will use for longer trips.

My main reason for the smaller battery is that when my kids (currently 8 and 10) get to college age, I plan to pass this car to them. At that point I can replace the worn battery pack with a larger one depending one (size depending on where the kids will be going to school). I think I saw a post from someone that Tesla says the range of the batteries will be increasing 10% per year (or was it cost reducing 10% per year). So this way I get to have my car now and have a long term plan for it later with more range.

Of course, this only takes care of one kid. Not sure how I am going to make both happy...

 

[ElSupreme]

I essentially don't want this scenario to happen:

Dude/Lady: "What kind of car is that?"
Me: "It's a Tesla Model S, its all electric"
Dude/Lady: "Looks pretty nice, is that an LCD In your car? How far does it go?"
Me: "Well this one goes 160 miles..."
Dude/Lady: "I don't know if I could own a car like that, I need more mileage"

Essentially I want the extra miles as well so that I can preach the gospel of EV's. lol

You can always answer with the weasley:

They can go up to around 300 miles!

It's not lying if you use a generic term for the Model S. If you don't like saying half truths you can respond with the:

Mine still goes 160 miles on a single charge. I don't need more so I didn't get the option.

People love having options!

 

[petero]

Bardlebee. I spent quite a bit of time debating 40 vs 60Kwh and decided on the 60. You never know how your future will change. A better job, a new home, etc. and all of sudden your commute is longer. You need to give yourself a comfortable cushion and you don’t know what the future will bring. These are my rough estimates based on talking to roadster owners, enthusiasts, and reading the TM forum.



First. Appraise your range needs and driving style. The 160 mile range is really closer to 125 (80% charged for battery longevity), if you drive at 55mph or less you will have plenty of cushion. If you drive the freeways at 75mph you will likely see the 125 range decrease to something like 95 miles. So you could be looking at a one way range of 50 miles, allow for an additional 20% degradation over an extended time. I estimate the 60kwh as follows: 230 less 20% = 185 miles, at 75 mph =148 mile range, allow for an additional 20% degradation over an extended time.



Second. Performance. Among the attractions of the “S” is performance. Smooth, quiet, and quick. 40 kwh=Zero to 60 in 6.5 seconds is fast. With the 60 the time drops to 5.9 seconds which is amazing when comparing the 85kwh at 5.6 (the performance 85 kwh is 4.4 seconds).



That is it from my perspective. I anticipate receiving my “S” in February 2013 (hopefully sooner) and my wife will take it away from a few days later.

 

[gkalexdc]

Here you go:

Reasons-to-upgrade-to-60kWh
Seeking-Pack-Size-VS-Degradation-and-Cost-Analysis-Info

And two more for luck:

Convince-me-I-need-a-bigger-battery
Arguments-for-the-160-mile-S-(if-you're-not-a-millionaire-of-course)

Thank you NigelM for doing these links! I very much appreciate it.
My next question for the group is to go through a scenario of range for the 300 mile pack in Texas, like the members did in the above replies. With 70 mph freeways ,A/C, and the 100 heat we have.
Another question is whatvdoesveveryone think about the higher heat degrading the packs .... Will that become a factor to consider in the pack we purchase.

 

[dsm363]

Thank you NigelM for doing these links! I very much appreciate it.
My next question for the group is to go through a scenario of range for the 300 mile pack in Texas, like the members did in the above replies. With 70 mph freeways ,A/C, and the 100 heat we have.
Another question is whatvdoesveveryone think about the higher heat degrading the packs .... Will that become a factor to consider in the pack we purchase.

If you want to comfortably travel along the Dallas/San Antonio/Houston triangle then you really want the 85 kWh pack. Driving 55 mph in a 75 mph isn't fun.
I don't think the heat will play a big factor other than your AC will be on more and it will use more energy to drive but with the battery being monitored and cooled, it shouldn't significantly decrease the battery performance/capacity over time compared to a cooler climate. I'm not certain about that though.

 

[gkalexdc]

I agree!! They have even raised the speed limits in some areas to 80mph . I am anxious to meet the other Tesla owners in the Texas Triangle and Supercharge between the cities!! Cant wait for your review ofbthe P85 dsm!!

 

[dsm363]

I agree!! They have even raised the speed limits in some areas to 80mph . I am anxious to meet the other Tesla owners in the Texas Triangle and Supercharge between the cities!! Cant wait for your review ofbthe P85 dsm!!

Sure. Good point. If they actually build out Superchargers in-between the major cities along the triangle then the 85 kWh pack isn't as important but still useful.

 

[jomo25]

If you want to comfortably travel along the Dallas/San Antonio/Houston triangle then you really want the 85 kWh pack. Driving 55 mph in a 75 mph isn't fun.
I don't think the heat will play a big factor other than your AC will be on more and it will use more energy to drive but with the battery being monitored and cooled, it shouldn't significantly decrease the battery performance/capacity over time compared to a cooler climate. I'm not certain about that though.

I'm not sure how it will be on the S, but on the Volt, the cooling does use energy. So, even if you can bear the heat, the battery can't so it has to burn energy to maintain the battery's temp. I think you are underestimating how much energy will be used on hot days.

 

[dsm363]

I'm not sure how it will be on the S, but on the Volt, the cooling does use energy. So, even if you can bear the heat, the battery can't so it has to burn energy to maintain the battery's temp. I think you are underestimating how much energy will be used on hot days.

I think gkalexdc was asking about the heat degrading the packs. I agree it will use more energy to keep the battery and the driver cool in Texas/Arizona but as long as the battery is kept in its comfortable range, it shouldn't degrade quicker at least from what I understand.

 

[jomo25]

I think gkalexdc was asking about the heat degrading the packs. I agree it will use more energy to keep the battery and the driver cool in Texas/Arizona but as long as the battery is kept in its comfortable range, it shouldn't degrade quicker at least from what I understand.

Right, there wouldn't be much/any degradation (permanent), but it will have an impact (temporary) on your range becasue of the extra energy consumed. I.e. when the weather's back to nice, you'll still have your full capacity and "normal" range back.

E.g. in my Volt, I used to get about 42 mi on a full charge in the PHX spring. Now in the heat, I only get about 34 mi with the same routine. In the fall, when temps go back down, I'll be back at 42 mi. But during the summer, Im seeing about 15% less mi range due to the extra energy spent on A/C and Temp Mgmt for the cooling of the battery.

 

[dsm363]

Right, there wouldn't be much/any degradation (permanent), but it will have an impact (temporary) on your range becasue of the extra energy consumed. I.e. when the weather's back to nice, you'll still have your full capacity and "normal" range back.

I agree. Your main point is important. Factor climate into your battery choice as well.

I think the 40 kWh car is good for either a city only car or if the 60 kWh car just isn't possible financially and you're willing to accept the limited range.

 

[gkalexdc]

I think gkalexdc was asking about the heat degrading the packs. I agree it will use more energy to keep the battery and the driver cool in Texas/Arizona but as long as the battery is kept in its comfortable range, it shouldn't degrade quicker at least from what I understand.

Thats exactly what i was asking about , and i think Tesla has taken great strides in battery management to make sure that whatnis hapening to he Leaf owners in AZ wont happen to Tesla owners. As a previous Leaf owner, i worried about the temp management, and one of the many pluses Tesla has is a non primitive , Active management. In these few posts i have, I should ask all to consider that areas with higherbtempertures willnmake the AC syems work not only to cool the passenger but also to actively cool the pack. Therefore , when considering battery sizes one should ask youself what is the size pack necessary to do all these functions of not only active pack temp management, along with the other obvious factors. I read above that higher temps can take 10 to 15% off your range.

 

[dsm363]

It doesn't look like the range calculator they have in the store is on the web yet but that gives you an idea of the hit AC will take and ambient temp as well. It allows you to adjust the temp up to 95 F I think.

 

[jomo25]

It doesn't look like the range calculator they have in the store is on the web yet but that gives you an idea of the hit AC will take and ambient temp as well. It allows you to adjust the temp up to 95 F I think.

Ya, the curve when you reach 110 is scary Seriously, my previously silent Volt does begin to sound like a jet when the TMS kicks in.

 

[jerry33]

You just totally threw Jerry under the bus! (You okay, Jerry?)

Yes, I'm fine, under the bus is pretty typical for me:biggrin: Mostly, if I can lift the computer, it's not big enough. But even for portable devices, I get the most available--they seem to last longer that way.