Nice to Know
previous: Driving the Trip
Regeneration
Regeneration (re-gen) is a form of battery charging. Re-gen is recovered energy that would otherwise have been lost. In ICE vehicles the friction brakes do the stopping. When you apply the brake pedal the forward momentum is converted to [air cooled brake system] heat. In and EV, deceleration occurs by relaxing foot pressure on the ‘gas pedal’. The magic of the system causes the motor to act as a generator. The work done slows the vehicle and product is returned to the battery for re-use. This conversion is between 60% and 70% efficient. One pedal driving is a skill to acquire and take satisfaction in. Plan ahead so as to never use the friction brakes if possible. Use the right pedal re-gen technique.*
*The most efficient way to drive or hyper-mile is to accelerate somewhere between an easy to moderate rate and then coast as much as possible.
Orange is acceleration and or steep incline hill.
Green shading depicts re-gen during deceleration and or hill descent
Range Indicator Science
Model 3 Motor
The Model 3 motor* has a design output of 202 kW at full effort. AC switched-reluctance partial permanent magnet synchronous motor, oil cooled, with variable frequency drive and as of 2019.36.1 firmware the Motor specs are:
- 320 v nominal voltage
- 800 A maximum current
- 192 kW (258 hp) prior to firmware update
- 202 kW @ 5,000 rpm maximum net power at motor speed (271 hp)
- 17,900 rpm maximum speed
- 420 Nm maximum torque (310 ft. lbs.)
*Correct terminology: an engine burns fuel whereas a motor uses electricity.
Sample evCalc
In the above example output the following variables were entered for a Tesla Model 3 Long Range RWD model with all season tires at recommended pressures but without aerowheel covers. The route from Cary, NC to Southport NC is a 172 mile journey via Interstate with gentle upslope and downslope consideration.
- zero wind
- dry road conditions
- 50° F OAT
At a constant speed of 70 mph the consumption result is 308 Wh/mi. The aerodynamic aerowheel [hubcap] cover improves the efficiency with 298 Wh/mi by comparison.
Relationship Between Wh and Miles
Presented below is a table listing the deviation from the EPA norm which is an average 260 Wh per mile (advertised in their test cycle loop and yours may vary).
| Wh | deviation | mile | x100 miles |
| 233 | -10.4% | 1.1 | |
| 234 | -10.0% | 1.1 | 110 |
| 235 | -9.6% | 1.1 | |
| 236 | -9.2% | 1.09 | |
| 237 | -8.8% | 1.09 | |
| 238 | -8.5% | 1.08 | |
| 239 | -8.1% | 1.08 | |
| 240 | -7.7% | 1.08 | |
| 241 | -7.3% | 1.07 | |
| 242 | -6.9% | 1.07 | |
| 243 | -6.5% | 1.07 | |
| 244 | -6.2% | 1.06 | |
| 245 | -5.8% | 1.06 | |
| 246 | -5.4% | 1.05 | |
| 247 | -5.0% | 1.05 | 105 |
| 248 | -4.6% | 1.05 | |
| 249 | -4.2% | 1.04 | |
| 250 | -3.8% | 1.04 | |
| 251 | -3.5% | 1.03 | |
| 252 | -3.1% | 1.03 | |
| 253 | -2.7% | 1.03 | |
| 254 | -2.3% | 1.02 | |
| 255 | -1.9% | 1.02 | |
| 256 | -1.5% | 1.02 | |
| 257 | -1.2% | 1.01 | |
| 258 | -0.8% | 1.01 | |
| 259 | -0.4% | 1 | |
| 260 | 0.0% | 1 | 100 |
| 261 | 0.4% | 1 | |
| 262 | 0.8% | -0.99 | |
| 263 | 1.2% | -0.99 | |
| 264 | 1.5% | -0.98 | |
| 265 | 1.9% | -0.98 | |
| 266 | 2.3% | -0.98 | |
| 267 | 2.7% | -0.97 | |
| 268 | 3.1% | -0.97 | |
| 269 | 3.5% | -0.97 | |
| 270 | 3.8% | -0.96 | |
| 271 | 4.2% | -0.96 | |
| 272 | 4.6% | -0.95 | |
| 273 | 5.0% | -0.95 | 95 |
| 274 | 5.4% | -0.95 | |
| 275 | 5.8% | -0.94 | |
| 276 | 6.2% | -0.94 | |
| 277 | 6.5% | -0.93 | |
| 278 | 6.9% | -0.93 | |
| 279 | 7.3% | -0.93 | |
| 280 | 7.7% | -0.92 |
Observe that if you are driving in ideal conditions that happen to match those of the EPA’s test loop then your car (will display energy usage at the rate of 260 Wh per mile) indicate one mile of indicated range usage for every 1 mile that you travel. But In reality when conditions are contrary and more energy is being used then those indicated miles won’t go quite as far — that is to say not one for one.
Take a look at the table. If the car is consuming energy at 273 Wh you can see the hit. 5%. Traverse the column and see that losing 5% of 1.00 miles computes to 0.95 miles. Under these conditions at the start of your journey an indicated range of 100 miles will only net you 95 miles actual ground covered. Compensate by charging to and indicated 105 range miles.
Range vs Speed and Temperature
Speed Effect on Wh/mile
Speed Effect on Range
AC Adapter Fun
NEMA 5-15 adapter for 120 Volt outlet up to 1,400 W 12 A @115 V is approx 3 to 4 mph
J1772 Standard Level 2 adapter is furnished with Tesla.up to 8,320 W 40 A @208 V is approx 22 mph
NEMA 14-50 adapter and using Tesla’s Gen 1 UMC* supports up to 250 V at 40 A (10 kW)up to 9,600 W 40 A @240 V is approx 38 mph
NEMA 14-50 adapter and using Tesla’s Gen 2 UMC* supports up to 240 V at 32 A (7.7 kW)up to 7,680 W 32 A @240 V is approx 31 mph
CHAdeMO adapter available for purchase $$$up to 62.5 kW by 500 V, 125 A DC
CCS Combo 2 adapter available for purchase ???
*Universal Mobile Connector (UMC) is an approx. 20 foot cable bundle that comes with the Tesla. It is proprietary with one plug end that goes to the wall outlet and a business end for the car’s charge port. See the description of NEMA outlets and the cable and adapters on the Tesla Mobile Connector Support site.
Tesla HPWC Wall Connector
aka Destination Charger are proprietary and you don’t need an adapter for them. They support up to 240 V at 48 A (11.5 kW) 48 A @240 V is approx 44 mph
Tesla Supercharger
Tesla’s Superchargers are proprietary and you don’t need an adapter for them. There are 3 versions 4 versions of Tesla Superchargers in the wild and supporting up to:
v4 250kW –new with longer cable
v3 250 kW ~ 160 miles range in 15 mins. with on-route battery warm-up (new and still uncommon)
- 9% – 23% = 4 minutes (average 11 miles/minute or 651 mph)
- 9% – 50% = 12 minutes (average of 10.6 miles/minute or 636 mph)
- 9% – 60% = 15 minutes (average of 10.5 miles/minute or 632 mph)
- 9% – 70% = 19 minutes (average of 10 miles/minute or 600 mph)
- 9% – 80% = 25 minutes (average of 8.8 miles/minute or 528 mph)
- 9% – 90% = 35 minutes (average of 7.2 miles/minute or 430 mph)
Example: arrive at a v3 SC with <9% battery charge remaining and charge to 70% in about 20 minutes or so. Note: Maximum power can be provided to each stall, there is no longer a concern about which stall to pick on a V3.
v2 145 kW ~ 160 miles range in 20 mins. (common)
- 4% – 25% = 10 minutes (average 8.1 miles/minute) 81 miles range
- 4% – 50% = 20 minutes (average 8.1 miles/minute) 162 miles range
- 4% – 75% = 35 minutes (average 6.9 miles/minute) 240 miles range
v1 120 kW ~ 150 miles range in 30 mins. ~$0.024/mi. (most common)
As you might observe from the charge taper characteristics the rate of charge is controlled and diminishes as the battery becomes filled. For this reason, to charge from 90-100% is not a good trade off. It takes a disproportionate amount of time to top-off. Charge to 70-80% and be on your way. Arrive with [your comfort] reserve range miles remaining in the battery and enjoy a fast charge leaving the supercharger station after about 30 minutes.
Supercharging with North Carolina Rates (7% state tax inclusive). Terms for your state may differ slightly.
- $0.24 per minute above 60 kW
- $0.12 per minute at or below 60 kW (or when sharing a SC cabinet) ~$0.03 /mile
- $0.50 per minute idle fee (charges begin 5 minutes after charge completion and with 50% station occupancy. This fee doubles if facility is 100% occupied.)
Take the Quiz
Test your EV Charging Knowledge Slow to Fast