Recent cross country trip

How much energy did you use. The unit of measure should be kWh, since that is easily convertible to all systems. Trying to use dollars to convert types of energy does not work well unless you include all prices and all quantities of everything at every step of the conversion.


Too bad there is no transparency at the supercharger to let you know how much energy it pulled from the grid for every kWh that it pumped into your car.

 

Most people will care just about what it costs them.

 

While that may be true, the "cost" is totally useless to anyone who does not drive the same car in the same area. For instance, I can relate that last week I drove 479 miles through northern California and it cost me $45.67 So how much good does that do you?

But if I told you that I did 38.7 miles on level freeways using 194 watts per mile on battery, well that's directly related to what you can expect no matter where you are or what you drive. If I then told you that I drove the rest of the way (440.5 miles) through multiple mountain passes at 80 mph with a head wind for an average of 50.63 miles per gallon, then that's another one that you can compare to your usage with other cars.

Those numbers, by the way, are exactly what my car reported for the trip last week. Yep. Not even the names have been changed to protect the innocent.

There have been trips that over or underperformed. Best gas usage was 71 MPG on a level freeway doing 65 MPH. Most frequent mileage on 500 mile trips (central cal to either southern California or Oregon) has been 61 MPG. Not too bad for a car that only cost $24,000.**

Dan

** If memory serves correctly.

 

It gives me an idea of how much it costs per mile compared to my car. Most people just know how it costs to fill their tank, and how often they fill it. They really only care about actual energy efficiency as far as it affects how much they pay. The OP did give specific start and end points with an average speed.

I'm not likely to be driving down to Bob's region, and if I go to California I'll be renting a car. So even knowing specific energy consumptions isn't going to give me much more info for comparing to my current car. It's fun to share the info, but of interesting trivia when compared to my data needs.

When I want compare the efficiencies of different models, I'll use EPA ratings. I know how my current and past cars did compared to their ratings, so I can infer what I'll get in another car.

 

If you know specific energy consumption, you can do comparisons that make sense. The cost of a tank of gas or the cost to charge at a supercharger is useless information; The supercharger cost varies a LOT from location to location and day to day, the same as the cost of gasoline.

But the amount of energy used per mile stays fairly constant under similar conditions.

I don't use the EPA ratings for much. They don't tell me what is possible with conservative driving. They only tell me what a certain car rated on a certain simulated course. The car is as likely as not to be tuned to do well on the test.

 

Bob, Your screen shot of the Tesla dashboard shows a lifetime average of 227 Wh used per mile. Your trip meter says that you used 221 Wh per mile on the trip, purportedly while driving at 48 MPH. That's a little worse than your average.

Are you claiming that you only use 73.8 Wh per mile in town? Really? If that were true, it should be making headlines across the country. What I see from your screen shot was 2 miles in 6 minutes using 209 Wh. That's what? 20 MPH?

I think you need to take some remedial math classes. None of your math ever adds up.

 

The EPA testing controls variables which allows like to like comparisons of different models. If you know what your energy efficiency is in your current car is on a route, they also used to estimate what you can get in another model. If you are getting, say 10% more than EPA in your car, you will very likely get 10% more with another car.

Tuning concerns are the opposite. There are rules in place to keep manufacturers from optimizing the cars too much for the test. Worn tires have lower rolling resistance for example. So the amount of wear is limited to about 4000 miles.

If you do something for fuel economy that takes the car out of factory spec, like having higher tire pressures, then that shows up in your ratio to the EPA rating.

 

i'm more concerned with charging time and number of stops

 

Aye, and there's the rub. The "too much" is evidently poorly defined and poorly enforced. VW is not the only one who has had cars that performed better on tests than they did in real life. They just got caught doing it.

 

But they cheated primarily on the emissions not the MPG efficiency, right?

Mike

 

My memory fails me on the details:
From Car and driver: In the test mode, the cars are fully compliant with all federal emissions levels. But when driving normally, the computer switches to a separate mode—significantly changing the fuel pressure, injection timing, exhaust-gas recirculation, and, in models with AdBlue, the amount of urea fluid sprayed into the exhaust. While this mode likely delivers higher mileage and power, it also permits heavier nitrogen-oxide emissions (NOx)—a smog-forming pollutant linked to lung cancer—up to 40 times higher than the federal limit. That doesn’t mean every TDI is pumping 40 times as much NOx as it should. Some cars may emit just a few times over the limit, depending on driving style and load.

 

A levelheaded unbiased look at Tesla operating cost. You would really have to take the time to read the whole article to understand the discussion, but it is a very easy read:

How Much Does It Cost to Charge a Tesla? (And is It Worth It?)

 

ouch, there was a lot of anti tesla bias hidden in thar article.

'is it worth it' is a strange question to ask or try to answer for someone else. prius owners have been asked that for years.

 

I missed the anti tesla part it just seemed to me they talked cost. My impression was they took the total cost-purchase price, insurance etc.

I am ambivalent about Tesla and my impression was that here are the facts, you need to do the figuring for your individual situation, but I have no strong felling either way for Tesla and that may lead me to not pick up on some things in the article.

Only posted it as thought it was neither for nor against Tesla just fact based.

If it was biased, I apologize as that wasn't my intent.

 

When the article is labeled "what does it cost to charge a Tesla", it should have max and minimum prices for charging within the target area for the article's readers. If it's targeted to American readers, it should have the high and low throughout the USA.

It should not have wording like "$0.26 is a common price that we see, so we will use that" for the calculations.

 

agreed. it should actually be an explanation of how to understand your electric bill