## Tuesday, June 5, 2012

### Vehicle Lifetime Cost Of Energy: Electric Vehicles Vs Internal Combustion Engine

Recently I was thinking about the total cost of gas over an Internal Combustion Engine (ICE) car's lifetime of about 200 thousand miles and ran some numbers on the question. It's a LOT!

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Cost of Gasoline Over The Vehicle's Entire Lifetime:

Assume an ICE vehicle's total mileage before it is scrapped is 200,000 miles. Assume it gets 25 MPG and gas costs \$4 per gallon.

200,000 mile / 25 MPG
= 8000 gallons of gas in the car's lifetime

8000 * \$4.00 per gallon
= \$32,000 for gas over the car's lifetime!

\$32,000 / 200,000
= 16 cents per mile, just for the gasoline

Over the lifetime of the car, 200K miles, the gasoline to drive it will cost \$32,000!

Even if the car runs on average at 35 MPG, the total cost of gasoline for the car's lifetime, is about \$22,857! When you think of it, the total cost for gasoline is about the cost of the car itself, and often even more! If you only get 15 MPG, the cost of gas over 200K miles will be \$53,333!

How Much Do Electric Vehicles Cost To Operate?

First, what kind of "MPG" do EVs get? How far does an EV travel on a single charge? Taking some popular samples:

Mitsubishi Miev has a stated range of 160 kilometers (100 mi) for the Japan 10-15 mode drive cycle with a 16 kWh lithium-ion battery pack.

100 miles / 16 kwh
= 6.25 miles per kwh
= 10 kilometers per kwh

Battery 53 kWh (Lithium-ion battery)
Electric Range 244 mi (393 km) using EPA combined cycle

244 miles / 53 kwh
= 4.6 miles / kwh
= 7.41 kilometers / kwh

24 kW·h lithium ion battery

Range 117 km (73 mi) (EPA)
175 km (109 mi) (NEDC)
76 to 169 km (47 to 105 mi) (Nissan)

Best:
109 miles/24 kwh
= 4.5416 miles per kwh
= 2.82 kilometers per kwh

Worst:
47 miles / 24 kwh
= 1.9583 miles per kwh
= 3.16 kilometers per kwh

This shorter range of 47 miles is consistent with tests of the Nissan Leaf in cold weather driving at -30 celcius (-22 Fahrenheit)!  In colder weather, the range is reduced. Excellent disclosure on Nissan's part to publish a worst case scenario number!

Electric Vehicle's Mileage Efficiency Scenarios:

Best case:
Mitsubishi MIEV
6.25 miles per kwh

Average Case:
Nissan Leaf Best case/Tesla Roadster are very similar
Use 4.5416 miles per kwh

Worst case:
Nissan Leaf at -30 celcius:
1.9583 miles per kwh

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Put the numbers into a spreadsheet. Use six cents per kilowatt hour.

200,000 miles/4.5416 miles per kwh
= 44037 total kilowatt hours

44037 total kilowatt hours * 6 cents per KWH
= \$2642.22

Comparing the energy costs side by side, the cost for electricity is around one tenth the cost of gasoline!

And the cost per mile is just as dramatic.

In  the average scenario, an ICE car costs 16 cents per mile, just for the gas.  An EV requires only 1.32 cents of electricity.

Note that the ICE costs are just the cost for the gasoline. It does not include the costs for oil changes, tune ups, radiator fluid changes, repairs, financing, or depreciation. Perhaps in another post, I'll detail all the other expenses. The point here is to show how dramatic the differences in operating costs for fuel vs electricity.

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Why Don't We Hear More About The Total Fuel Cost Over The Entire Life Cycle Of A Car?

One reason is perhaps that the buyers of new cars are not thinking into the future 200K miles and 10 or more years. They are thinking of a 3 to 5 year time span. Leases are often for 3 years. After that, the buyer plans to buy another new prestigious car.

When they buy, the biggest visible cost is the price of the vehicle, at \$20K, \$30K, \$40K, \$50K or more. Gasoline at \$4 or even \$5 per gallon does not seem like big expense. Like smokers who do not think of the health consequences of one more cigarette, car buyers do not think much of the long term cost of gasoline.

From a consumer behavior standpoint, they are thinking heavily about: features, financing, car payments, tax write offs, style, color, how it drives, excitement, showing off, status. Or, perhaps an end to the problems that an existing car is giving them.

Even if they did think of the long term fuel costs, they are probably only thinking of fuel costs in terms of the time they will personally own the car. Not about the life of the car after they trade it in for the next vehicle. Even at 20K miles per year, the 5 year cost of fuel for a car that gets 25 MPG is:

20K miles per / year * 5 years
= 100K miles

100k/25 mpg
= 4000 gallons

4000 gallons * \$4 per gallon
= \$16K

"Only" \$16K. Which is probably still less than the price of the car. A Camry or Accord easily sells for over \$30K new. The gas expense is still smaller over that time period.

However, when they do eventually drive 200K, they will have spent just as much for the gasoline over the same time period.

But I think a big reason why we don’t think of the total cost of gas, is probably because it's just not mentioned. If the sales reps, media, and general public thought in these terms, car companies would probably sell a lot fewer cars!

If they want to sell more EVs, perhaps they can just broadcast a few of these TCO numbers.

Happy driving and financing.

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Further:  The Costs For Fleets

I found some articles on the lifecycle costs for fleets. What's interesting, is that they don't really seem to consider the price or total cost of gasoline very much. Why?

Automotive Life Cycle Economics and Replacement Intervals

This paper from 2004 covers a lot of the scheduled maintenance that needs to be done to a car. Financing. Insurance. Whether to buy new or used. How long to keep the vehicle. Car values. Depreciation. CO2 emissions. Gasoline taxes. It does consider various technologies to improve fuel economy. But it does not detail the total cost of gas that the owner will pay while driving the vehicle over the time period.

Vehicle Lifecycle Costs Analysis

This paper from Automotive Fleet, 2003, is a compilation of a number of articles from different writers. It was sponsored by Toyota.

The first writer, Peter Klopchic from CitiCapital Fleet, states that the two biggest direct costs are depreciation, and maintenance over the first two years. But not fuel. Odd. The maintenance charges on a brand new vehicle cost more than the gas? I disagree with depreciation being a direct cost. In accounting, depreciation is always an indirect cost, never direct. He also lists Indirect Costs as being Perk Value, Corporate Image, and Downtime, items that I have never heard of on an income statement. However, I have heard of these in sales and marketing. I'll conclude that he is not an accountant, but works in fleet sales.

Other writers mention fuel efficiency. One quotes a number of fleet managers who consider MPG. Not surprisingly, some of these fleet managers also mention the Toyota Prius. One mentions that his Prius averages 44 MPG. However, again, the total cost of gas is not detailed over the TCO.

Terry Flesia from AutoCross & Associates, a fleet consulting firm in Irvine, CA, commented on fleet expenses, going back to the 1950s. In particular, fuel and depreciation expense.  Unfortunately, he combines these two expenses into one: "total fuel/net depreciation cost-combination", and does not provide a detailed example for explanation.  So, it's unclear what percent the fuel expense really is, or was.

The main thrust of all the writers in this PDF seem to be the cost of depreciation. Not fuel or other expenses.