COMPARISON OF TESLA MODEL 3 AND MODEL S

The main purpose of this article is to determine how much AC electricity has to be drawn from the wall socket to have one kWh of DC in the battery. This appears straightforward, but it is not, because it takes energy to convert from AC to DC and to overcome the internal resistance of the battery.

Also, once the electricity is in the battery, it is used to operate the vehicle’s systems, whether in motion or not, such as heating/cooling the cabin and battery. That electricity loss is called vampire loss; it is not available to get from A to B.

 

People who park their EV at an airport and come back two weeks later may be in for a surprise, because they have much less charge in the battery than when they left. As a result of these losses, significant additional electricity needs to be generated by power plants.

It is important to understand, due to the charging/vampire loss, it takes the Tesla Model S, driven in upstate New York (similar conditions as New England) about 0.434 kWh/mile of AC electricity from the wall meter to provide 0.333 kWh/mile of DC electricity in the battery. See tables 1, 1A, 2, 3 and 4

 

Table 1A
Tesla Model	Location	Charging/vampire loss factor
S	Upstate New York	0.434/0.333 = 1.3030
3	Southern California	0.308/0.245 = 1.2573

 

NOTE: Vermont grid load (electricity fed to grid) was about 6.0 TWh in 2018. If all Vermont light duty vehicles using gasoline were to be replaced by EVs, the additional grid load would be about 3.075 TWh. Heat pumps would be in addition. Any vehicles using diesel fuel are not included. See table 1.

 

A Tesla Model S costs about (8.24 c/mile)/(5.85 c/mile) = 1.41 times more to drive per mile than a Tesla Model 3, because:

 

-  It is a heavier vehicle  

-  It is based on older technologies

- The Model S is driven in upstate NY and the Model 3 is driven in southern California

 

Table 1
Vermont LDV travel, billion mile/y	6.272
Electricity stored in battery for a mix of LDVs, as DC, kWh/mile	0.350
Charging/vampire loss factor in NE	1.303
Electricity transmission and distribution loss factor	1.075
Electricity to be fed to NE grid to charge EVs, TWh/mile	3.075

LONG-TERM ROAD TEST OF TESLA MODEL 3 

 

Edmunds, in California, has been performing a long-term road test of a Tesla Model 3 since January 2018. Here are the latest results from the Edmunds website.

https://www.edmunds.com/tesla/model-3/2017/long-term-road-test/2017...

 

- Edmond one-year average mpg, with various drivers, various road trips, was about 30.80 kWh/100 miles, based on wall meter

- February, March and April were not shown, because of missing data. See table 2 and URL

- EV drivers know little of the charging/vampire loss; they rely on the lower numbers of the EV meter.

https://insideevs.com/monthly-plug-in-sales-scorecard/

 

In colder, hilly upstate New York (and New England) greater losses would be expected than in warmer, flat southern California.

 

NOTE: EPA combined for a 2018 Tesla Model 3, AWD, long-range, is 29 kWh/100 miles, wall meter basis, or 0.29 x 0.85 = 24.65 kWh/100 miles, vehicle meter basis. See table 2 and 3 and URL

https://fueleconomy.gov/feg/bymodel/2018_Tesla_Model_3.shtml

 

NOTE: The EPA tests in a laboratory based on wall meter, but does not account for real-world driving conditions, such as vampire loss, hot and cold weather operation, road conditions, snow, hilly terrain, more than one person and/or cargo in a vehicle. As a result the real-world consumption during the Edmund test was about 30.80 kWh/100 miles. See table 2.

https://www.fueleconomy.gov/feg/PowerSearch.do?action=noform&ye...

Table 2 shows the data recorded by Edmunds during the long-term road test of the Tesla Model 3

 

Table 2/Tesla Model 3	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct
Odometer	1388	2922	3937	5237	6009	6659	7679	9329	10307	11174
Travel/month, miles		1534	1015	1300	772	650	1020	1650	978	867
Wall meter, kWh/100 m
Real-world average	31.70				31.40	31.80	31.70	31.00	31.10	30.80
EPA combined	29.00				29.00	29.00	29.00	29.00	29.00	29.00
Vehicle meter, kWh/100 m
Real-world average	25.17				24.83	25.03	25.09	24.76	24.70	24.49
EPA combined	24.65				24.65	24.65	24.65	24.65	24.65	24.65

 

Table 3 shows the electricity from the wall meter, charging loss, vampire loss, the electricity available for driving and the loss factor.

Table 3/MODEL 3, 2019, 100 kWh		%	kWh	kWh/mile	Basis
EPA combined, WM basis				0.2900
EPA combined, VM basis	0.290 x 0.85			0.2465
.
		%	kWh/y
Real-world driving, WM basis	3442/11174		3442	0.3080
Charging loss,	3442 x 0.15	15.00	516		WM
In battery, as DC,	3442 - 516		2925		VM
Vampire loss, as DC	100 x 188/2925	6.43	188		VM
Available for driving, as DC	2925 - 188		2737		VM
Miles driven			11174
Real-world driving, VM basis	2737/11174			0.2450
Charging/vampire loss factor	0.3080/0.245			1.2573
.
Electricity cost, c/kWh		19
Travel cost, c/mile	19 x 3442/11174	5.85

 

ONE-YEAR EXPERIENCE WITH A TESLA MODEL S

 

An upstate New York owner of a Tesla Model S measured the house meter kWh, vehicle meter kWh, and miles for one year. There was significant kWh/mile variation throughout the year.

 

- The Model S has regenerative braking as a standard feature.

- The owner did not take into account the source-to-house electrical losses.

- New EVs would have less kWh/mile than older EVs, due to battery system aging.

- Data as measured by owner in New York State covers only the driving energy. The embedded energy and its CO2 are ignored.

 

See URLs, especially the second, which has a wealth of data.

 

http://www.greencarreports.com/news/1090685_life-with-tesla-model-s...

http://www.uniteconomics.com/files/Tesla_Motors_Is_the_Model_S_Gree... 

About 1275 kWh of supercharger power was used for 4,000 miles of road trips, or 0.319 kWh/mile, per vehicle meter.

About 3799 kWh was used for 11243 miles of general driving, or 0.339 kWh/mile, per vehicle meter

Total 5074 kWh for 15243 miles, or 0.333 kWh/mile, per vehicle meter. See table 4

 

His real-world annual average was 0.434 kWh/mile, wall-meter and supercharger meter basis, and 0.333 kWh/mile, vehicle-meter basis; owners may use more or less than 0.434 kWh/mile in other US regions. 

In colder, hilly upstate New York (and New England) greater losses would be expected than in warmer, flat southern California.

 

NOTE: EPA combined for a 2019 Tesla Model S, AWD, 100 kWh battery, is 350 kWh/100 miles, wall meter basis, or 0.350 x 0.85, charging efficiency = 0.298 kWh/mile, vehicle meter basis. See URL

https://www.fueleconomy.gov/feg/PowerSearch.do?action=noform&ye...

 

NOTE: The EPA tests in a laboratory based on wall meter, but does not account for real-world conditions, such as vampire loss, hot and cold weather operation, road conditions, snow, hilly terrain, more than one person and/or cargo in a vehicle. As a result the real-world consumption is about 33.3 kWh/100 miles, vehicle meter basis. See table 4.

 

NOTE: It is important to understand it takes 0.434 kWh/mile of AC electricity to provide 0.333 kWh/mile as DC electricity in the battery. See table 4, which shows the electricity from the wall meter, charging loss, vampire loss, the electricity available for driving, and the loss factor.

NOTE: The charging and discharging of an EV battery is similar to having slowly increasing gas filling losses, due to a more and more leaky hose, into a slowly shrinking, slightly leaky, fuel tank*, plus having slowly decreasing miles per gallon, as your gasoline vehicle ages.

 

* In case of EVs, the growing losses of electricity are due to:

 

1) Slowly increasing charging/discharging losses (due to battery internal resistance increasing with age), into a battery, which has a capacity slowly decreasing with age; and

2) slowly increasing vampire losses.

 

Table 4/MODEL S, 2019, 100 kWh		%	kWh	Miles	kWh/mile	Basis
EPA combined, WM basis					0.350
EPA combined, VM basis	0.350 x 0.85				0.298
.
Three long road trips			1275	4000	0.319	VM
General driving			3799	11243	0.339	VM
Real-world driving			5074	15243	0.333	VM
.
		%	kWh/y
Real-world driving, WM basis	6614/15243		6614		0.434
Charging loss	6614 x 0.15	15.00	992
In battery, as DC	6614 - 992		5622			VM
Vampire loss, as DC	1.5 kWh/d x 365 d	9.74	548			VM
Available for driving, as DC	5611 - 548		5074			VM
Miles driven			15243
Real-world driving, VM basis	5074/15243				0.333
Charging/vampire loss factor	0.434/0.333				1.303
.
Interim readings		kWh/mile	EPA
	Apr-Oct	0.301	0.298			VM
	July	0.290	0.298			VM
	Nov-Feb	0.371	0.298			VM
	Jan	0.400	0.298			VM
.
Electricity cost, c/kWh		19
Travel cost, c/mile	19 x 6614/15243	8.24

COMPARISON OF CO2 EMISSIONS OF TESLA MODEL S AND NE FLEET OF LDVs

Source energy = upstream + primary energy

The source energy of fuels for power plants is from oil and gas wells, and coal mines, etc.

The upstream energy is for extraction, processing, transport, etc., of the fuel to power plants; about 17% of primary energy for NG, about 8% for nuclear, about 2% for hydro, and about 5% for wood chip electricity.

 

Example: A Tesla Model S was driven upstate NY, which has weather and road conditions similar to Vermont. Winter performance required significant greater kWh/mile than summer performance, largely due to:

 

- Worse road conditions,

- Heating seats, cabin, and battery, and

- Defrosting glass, wipers and mirrors, and

- The battery having more internal resistance during cold weather.

 

The owner kept data logs of relevant operating parameters for a year. See URL.

 

The log of the odometer showed 15,243 miles.

The log of the vehicle meter showed 5,074 kWh, or 0.3329 kWh/mile.

The log of the wall meter showed 6,614 kWh, or 0.4339 kWh/mile.

The charging + self-use loss is 6614 – 5074 = 1,540 kWh, or 0.1010 kWh/mile.

Charging loss is about 15% of 0.4339 = 0.0651 kWh/mile.

Self-use loss is about 0.1010 – 0.0651 = 0.0359 kWh/mile. See URL table 4, and see below table 10

http://www.windtaskforce.org/profiles/blogs/comparison-of-tesla-mod...

 

Comments on table 5:

The table shows the source energy required, to achieve 0.3500 kWh DC in the battery for A to B travel, after all losses.

It was assumed a mix of LDV, including cars, SUVs, crossovers, minivans and ¼-ton pick-ups, would require about 0.3500 kWh from the battery to travel one mile.

The current US mix of LDVs is about 50% SUVs and ¼-ton pick-ups, most of which have all-wheel-drive.

If charging and self-use losses are added, about 0.4563 kWh/mile would be drawn via the wall meter.

Electricity consumption for a mix of LDVs in NE would be 12,000 mile/y x 0.4563kWh/mile, wall meter = 5,475 kWh/y

The charging loss occurs during charging the batteries, about 15% for a Tesla Model S, or 0.15 x 0.4563= 0.0684 kWh/mile.

The self-use loss takes place while the EV is parked or driven, about 0.1062 - 0.0684 = 0.0378 kWh/mile.

 

NOTE: Edmunds, one of the largest car dealers in California, kept similar data logs of a Tesla Model 3.

Table 5A shows the data for the Model S and Model 3.

The Model S is a fuel-size, AWD sedan, the model 3 is a compact, AWD sedan.

The Model 3 is more efficient, because of later technology.

Driving, road and climate conditions in southern California are much better for EVs than in upstate New York.

Almost 50% of all EVs on US roads are in California, i.e., less kWh/mile!! See URL

http://www.windtaskforce.org/profiles/blogs/comparison-of-tesla-mod...

 

Table 5A/Model S and 3	Tesla Model S	Tesla Model S	Tesla Model 3	Tesla Model 3
		kWh/mile		kWh/mile
Miles	15243		11174
VM. kWh	5074	0.3329	2737	0.2449
WM, kWh	6614	0.4339	3442	0.3080
Charging + Self-use	1540	0.1010	705	0.0631
Charging loss, 15% of WM	992	0.0651	516	0.0462
Self-use		0.0359		0.0169

  

Table 5/NE grid	LDV mix	Tesla	Tesla	NE grid CO2	NE grid CO3
		Model S	Model 3	PE	SE
	kWh/mile	kWh/mile	kWh/mile	gram/kWh	gram/kWh
Source energy	1.2291	1.1713	0.8315
Upstream for extraction, processing, transport, etc., 10.2%	0.1138	0.1084	0.0770
Primary energy	1.1153	1.0629	0.7545
Efficiency loss, 55.5%	0.6078	0.5793	0.4112
Gross electricity generation	0.5075	0.4836	0.3433
Plant self-use loss, 3.0%	0.0152	0.0145	0.0103
Net electricity generation = Fed to grid	0.4922	0.4691	0.3330	310	342
T&D loss, 7.5%	0.0369	0.0352	0.0250
Fed to wall meters, as AC	0.4553	0.4339	0.3080	335	369
Charging loss, 15%	0.0683	0.0651	0.0462
Self-use loss, about 7%	0.0370	0.0359	0.0169
In battery a mix of LDVs in NE, as DC	0.3500	0.3329	0.2449	436	480
.
Travel, miles/y	12000	15243	11174
Wall meter electricity, kWh/y	5475	6614	3442
2 EVs	10950

 

Electric Vehicles CO2 Emissions

 

The CO2 emissions were 682 lb/MWh, or 682 x 454/1000 = 310 g/kWh, as fed by power producers to the high voltage grid. Excludes CO2 emissions of upstream energy.

https://www.iso-ne.com/static-assets/documents/2019/04/2017_emissio...

 

- 310 g CO2/kWh, primary energy basis, would be about 342 g CO2/kWh, source energy basis.

- 335 g CO2/kWh, primary energy basis, would become 369 g CO2/kWh, source energy basis.

- The CO2 is 0.4553/0.3500 x 335 = 436 g/kWh, if the battery charge change is used for calculating CO2 emissions, primary energy basis, or 480 g/kWh, source energy basis.

- Downstream not included.

If ALL Vermont light duty vehicles using gasoline were replaced by electric vehicles, and the charging/vampire loss factor were 1.303 (same as a Tesla Model S in NY), and the “in battery” kWh/mile as DC were 0.350, and the travel were 6.272 billion miles per year, then the electricity drawn, via wall meters, would be 6.272 b miles/y x 0.350 x 1.303 x 1.075, T&D  = 3.075 TWh/y.

 

The annual CO2 emissions, fuel only during the driving phase, would be 3.075 TWh/y x 335 g/kWh x 1 metric ton/million g = 1,030,125 metric ton/y. The ISO-NE grid is “clean”, i.e., low CO2/kWh, compared to the rest of the US.

 

NOTE: Excluded is the CO2, due to extraction of minerals from sources (mines, wells, fracking) for vehicle and battery pack manufacturing, and processing and transport of the materials to users and to infrastructures engaged in battery/vehicle manufacturing and delivery to customers, repairs/replacements during the driving phase, and processing/storage/landfill during the decommissioning phase.

http://www.windtaskforce.org/profiles/blogs/ifo-institute-study-cas...

 

Gasoline Vehicle CO2 Emissions

 

Burning a gallon of E10 produces about 17.6 pounds of CO2 from the fossil fuel content, about 18.9 pounds of CO2, if emissions from ethanol are included.

 

The average mileage of Vermont LDVs was about 20.713 miles/gal of E10 (90%gasoline/10% ethanol), in 2016

 

The annual CO2 emissions would be 6.272 b miles/y x 1/20.713 x 18.9 lb/gal x 1 metric ton/2204.62 lb = 2,595,919 metric ton/y; upstream CO2, due to extraction, cropping, processing and transport, is excluded.

 

Excluded is the CO2, due to extraction of minerals from sources (mines, wells, fracking) for vehicle manufacturing, and processing and transport of the materials to users and to infrastructures engaged in vehicle manufacturing and delivery to customers, repairs/replacements during the driving phase, and processing/storage/landfill during the decommissioning phase.

http://www.windtaskforce.org/profiles/blogs/ifo-institute-study-cas...

 

Table 6/Electric Vehicles		IC Vehicles
3.075	TWh/y, fed to wall meters	6.272	billion miles/y
335	g/kWh, fed to meters	20.713	miles/gal
1000000	g/metric ton	18.9	lb CO2/gal of E10
		2204.62	lb/metric ton
1,030,125	metric ton CO2/y	2,595,919	metric ton CO2/y

 

APPENDIX 1

Here is an article that fairly sums up some of the issues of electric vehicles.

https://www.marketwatch.com/story/youll-save-money-on-gas-with-a-te...

 

APPENDIX 2

VT Department of Transportation and the VT Public Utilities Commission want to subsidize EVs so they would be affordable for households with incomes of $92000. That would include almost all legislators. It pays to vote for being green. That income number should be reduced to about $50,000.

 

Roisman, head of VT-PUC, is claiming Vermonters, ready or not, have to use EVs, as otherwise the Comprehensive Energy Plan goal will not be met, and the world will come an unfortunate end in just 12 years!!! 

 

A Tesla Model 3, with four-wheel-drive and longer range, which is HIGHLY ESSENTIAL in Vermont, with low temperatures, hills and snow-covered roads (CAUSING LOSS OF RANGE. See below URLs.), costs about $52,000 (per Tesla quote, which includes minimal extras, and federal tax credit), plus sales tax, etc., about TWO TIMES the price of a Subaru Outback with four-wheel drive. Mine gets about 30 mpg.

The Subaru is FAR MORE USEFUL for Vermonters (high road clearance), the reason so many of them are sold in Vermont and all of New England. 

If rental fleets calculated EVs had a lower owning and operating cost versus gasoline vehicles, they would buy them by the tens of thousands.

CO2 Reduction is Minimal: It turns out, according to numerous studies, ON A LIFETIME BASIS, the CO2 reduction versus efficient gasoline vehicles is minimal, if upstream CO2 and downstream CO2 are included, even with the NE grid slowly getting cleaner, less CO2MWh, due to increased wind on pristine ridge lines and solar on open spaces and meadows. 

Subsidizing EVs would be at a VERY HIGH cost per metric ton of CO2 reduced, especially for an asset with such a short useful life.

 

Here are the 10 electric vehicles with the longest ranges (more than 200 miles on a full battery) in 2019

https://www.kbb.com/car-reviews-and-news/top-10/longest-range-elect...

 

Table 7/Electric Vehicles
Mfr.	Model	Battery	4WD	Standard Range	Starting price
		kWh		miles	$
Tesla	S	100	yes	335	86200
Tesla	3	75	yes	310	52200
Tesla	X	100	yes	295	97000
Hyundai	Kona	64	no	258	36450
Kia	Soul	64	no	243	35000
Kia	Nero	64	no	239	37500
Chevy	Colt	60	no	238	37495
Jaguar	I-Pace	90	no	234	70495
Nissan	Leaf Plus	62	no	226	37485
Audi	e-tron	95	no	204	74800

 

APPENDIX 3

Electricity Mix Based on Power Purchase Agreements: There are non-technical people talking about the “Vermont electricity mix” or the “New Hampshire electricity mix”. That mix exists only on paper, because it is based on power purchase agreements, PPAs, between utilities and owners of electricity generators. A utility may claim it is 100% renewable. This means the utility has PPAs with owners of renewable generators, i.e. wind, solar, biomass, hydro, etc. That mix has nothing to do with physical reality.

 

Electricity Mix Based on Physical Reality: Once electricity is fed into the NE electric grid by any generator, it travels:

 

- On un-insulated wires, as electromagnetic waves, EM, at somewhat less than the speed of light, i.e. from northern Maine to southern Florida, about 1800 miles in 0.01 of a second, per College Physics 101.

- On insulated wires, the speed decreases to as low as 2/3 the speed of light, depending on the application.

 

If those speeds were not that high, the NE electric grid would not work, and modern electronics would not work.

 

The electrons vibrate at 60 cycles per second, 60 Hz, and travel at less than 0.1 inch/second; the reason it takes so long to charge a battery.

 

It is unfortunate most high school teachers told students the electrons were traveling.

Teachers likely never told them about EM waves, or did not know it themselves.

http://www.djtelectricaltraining.co.uk/downloads/50Hz-Frequency.pdf

 

This article explains in detail what happens when electricity is fed to the grid.

http://www.windtaskforce.org/profiles/blogs/popular-misconceptions-...

 

NOTE: If you live off the grid, have your own PV system, batteries, and generator for shortages and emergencies, then you can say I use my own electricity mix. If you are connected to the GMP grid, which is connected to the NE grid, and draw from any socket, then you draw the NE mix.