Why am I getting 330+ Wh/mi?

[chrisbac]

Everything I am reading, people are getting mid to high 200's for Wh/mi but I have had my car just 2 weeks and gotten average 325 and often much worse on a trip. This includes a 180 mile trip I took all at highway speeds where I started with over 300 mi charge and got warning I have to go less than 65 to make it home, and we had to end up hitting a supercharger. This see4ms WAY off from predictions and other's reported usage. I was using autopilot most of the way of the 180 mi trip as regular highway speeds.

I understand that quick starts and cold weather will impact the reported Wh/mi,, but this has happened with both cold (~30F) and moderate (~55F) temperatures, but this seems way out of line with even that.

Thanks for ideas.

Chris

 

[Zoomit]

Naw, just cold

 

[MorrisonHiker]

What wheels do you have installed?

 

[tccartier]

Everything I am reading, people are getting mid to high 200's for Wh/mi but I have had my car just 2 weeks and gotten average 325 and often much worse on a trip. This includes a 180 mile trip I took all at highway speeds where I started with over 300 mi charge and got warning I have to go less than 65 to make it home, and we had to end up hitting a supercharger. This see4ms WAY off from predictions and other's reported usage. I was using autopilot most of the way of the 180 mi trip as regular highway speeds.

I understand that quick starts and cold weather will impact the reported Wh/mi,, but this has happened with both cold (~30F) and moderate (~55F) temperatures, but this seems way out of line with even that.

Thanks for ideas.

Chris

there are so many variables it's almost impossible to put one's finger on what is going on with your particular scenario. There could be tire pressure or alignment issues headwinds how much weight is being carried in the car along with many others. And keep in mind the battery is a large thermal Mass so it is not going to change temperatures as fast as ambient temperatures do. cold weather performance at least in so far as the battery is concerned is a function of the temperature of the battery pack not of the ambient air temperature.

 

[Daniellane]

Is your car a long range RWD with aero wheels?

 

[MP3Mike]

This includes a 180 mile trip I took all at highway speeds

What do you consider "highway speeds"?

 

[OCRyan]

Temperature and speed are the largest factors, my guess is your road trip is comprised of higher speeds. Speed to energy consumption is not linear. These graphs help to understand the relationship:

Tesla Range Plotted Relative To Speed & Temperature (Graphs) | CleanTechnica

 

[chrisbac]

What wheels do you have installed?

Standard 18" with aero caps on.

 

[TexasEV]

Did you have the heat on? That’s the biggest factor in energy consumption after speed. Use the seat heaters to keep the cabin temp set lower than you normally would.

 

[chrisbac]

Is your car a long range RWD with aero wheels?

AWD Aero wheels.

 

[chrisbac]

What do you consider "highway speeds"?

between 70 - 80 is common around here.

 

[chrisbac]

Did you have the heat on? That’s the biggest factor in energy consumption after speed. Use the seat heaters to keep the cabin temp set lower than you normally would.

Heat was on, but set to 68, but that can contribute I see.

 

[Msjulie]

between 70 - 80 is common around here.

My car is noticeably more efficient, using the new energy app, at 65 and less - it jumps quite a lot above that..

I have 19"OEM rims, inflated at the higher end of the suggested pressure

 

[MorrisonHiker]

What direction where you heading? Did you have strong headwinds? When I drove a 3 over 1000 miles a few weeks back, we were averaging over 350 Wh/mile driving west across windy Wyoming at 80 mph. Shortly after we entered Utah, the average dropped to 280 Wh/mile or less. This was with the 19" sport wheels, inflated to ~45 PSI, I believe.

 

[TexasEV]

between 70 - 80 is common around here.

Air resistance increases exponentially with speed. There’s a big difference in energy consumption between 70 mph and 80 mph. Even dropping your speed by 5 mph can make a noticible difference. The same is true for ICE cars but people don’t seem to care as much about energy consumption in ICE cars.

 

[glide]

between 70 - 80 is common around here.

There’s part of your answer. Keep it at/under 60 if you are looking to get the rated range.

As others have said, cold, elevation, cabin heat, driving style also contribute.

 

[SomeJoe7777]

As others have said, biggest factors are:

1. Speed -- go 70 or 72 MPH max. Efficiency starts to take a nose dive above this.
2. Cabin heat -- use seat heaters instead or seat heaters + low cabin heat (set to max of 68F)

Some other items that can affect your efficiency:

1. AWD will get slightly less range than RWD
2. Check tire pressures especially in the cold since cold temperatures will reduce your tire pressure. Inflate to 45 psi cold for a road trip
3. Brand new tires will have higher rolling resistance until they break in and develop easier flexion.
4. Headwinds can be a huge factor, check weather reports. If you have a strong headwind, slow down even more.

 

[TexasEV]

There’s part of your answer. Keep it at/under 60 if you are looking to get the rated range.

I got the rated range averaging about 70 mph on a long trip. But that was in the summer.

 

[iaflyer]

The car was designed in California - so "cold" for them is 55F. As others have said, cabin heat, going fast (above 65), winds and cold weather will all take away range.

Plan carefully and always take your mobile connector!

 

[DR61]

The car was designed in California - so "cold" for them is 55F.

Common misconception. California is huge and has a diverse climate. For instance the pass on I80 between the Sparks, NV Gigafactory and the Fremont factory has more average snowfall than most parts of Michigan.

Agree about speed (EPA average test speed is around 55 MPH) and cabin heat. EV's (all of them) don't have enough waste heat to adequately heat the cabin, so must use battery energy for that if demanded.