Prius Prime XSE/XSE Premium dismal BEV range

That 4.3 mi/kWh figure exactly matches my average car reported efficiency in 1119 EV miles in 2023 Prius Prime XSE under similar driving approach and prior vehicle (2009 Prius for 14 years).

 

This is with a ~50/50 mix of highway and city driving including several long, overnight trips. Just like in the Prius, it is pretty easy to beat the EPA estimates, especially with the base model with a single motor. We don't drive conservatively and just enjoy the car, especially since energy is relatively inexpensive, even here in CT where we pay more than average for electricity (~$0.21 / kWh). I don't think the car's measurement includes the non-driving energy use such as pre-heating/cooling, though I am not certain.

Over the 6 months and 7,500 miles we have owned the car, the average has been pretty steady. We had some hot summer driving, but only caught the tail end of the winter. I will see how it averages over the year to get a full year picture.

I think like the Prius, it is easy to get below, at, or above EPA figures since your right (or left) foot has a large influence on efficiency.

 

Maybe it's the drivers
TL/DR: Put a Prius driver in a Tesla and you can beat the average.

Here is a study with a 99 sample size that seems to back this up.
Your Tesla May Be More Efficient Than Its Driver

 

Can you explain what "mpge on the wall watt-hour meter" means?

 

33.7 multiplied by miles per kWh from the wall reading.

33.7 kWh in one gallon of gas.

That is my understanding.

 

Huh? Look I understand the mpg energy equivalency, but what does it have to do with the wall power?

Everyone’s EVSE is in the middle so there is no such thing as “4.3 mi/kWh at the car, is 100/4.3 divided by 33.7 “miles per gallon equivalent at the wall”. I don’t understand the meaning of “gallons at the wall”

My level 1 charging “at the wall” places a 35% tax on my at the car 4.3 mi/kWh turning it into 3.2 mi/kWh “at the wall”.

 

That is confusing to me.
What would that calculate?

You obviously have more time driving under you belt and making these calculations just trying to understand what you are saying.

 

I am saying I am confused

 

I've this entire thread and understood about 60% of it - but I think "gallons at the wall" is a calculation of what it costs (in electricity) to charge the car and convert that number to what it costs to buy an equivalent number of miles in gas.

So 2 hours of charging costs $2 and gives you 20 miles of battery driving
Driving on the gas engine for 20 miles would cost you $5 in gasoline
(wildly wrong numbers, just an example people)

The calculation they're using is a conversion for that to make the miles driven on electric have a direct relationship to the miles per gallon we normally refer to on gas engines.

At least that's what I understand it to be - someone please correct me (in normal language without acronyms or equations) if I've gotten it wrong.

 

Speaking of "no it's not" .... Iran pays roughly 15,000 iranian rial (about 36¢) per liter .... of which it takes over 3¾ liters to make a gallon.
IE; you're off by a factor of over 10

Factor in average income in a big city like Tehran ... the income expense would feel like one was paying between $3 & $4 USD per gallon.
.

 

EPA fuel efficiency calculations are based on the amount of fuel that went into the car. That means from the pump for the liquid ones, and from the outlet for electricity. For a plug in, that means the official mpge figure is including the charging losses. Tracking efficiency from what the car reports it used will yield a better result, as it doesn't include those losses.

Which is better for you to track depends on your goals. Wanting to know how efficiently you are driving, and trying to improve that, the car reported, from the battery is fine. Want to track more, like costs or comparing directly to EPA, you need from the outlet. The consumption the EVSE reports is good enough for most. There are options for when it isn't.

Are you charging with the supplied EVSE from a 15 amp outlet? Faster charging can reduce the losses if that is a desire.

 

Mine says 19%of charge used for 26km.

Running off the top of the tank, er, battery

 

That is a much better explanation, thank you!

If I understand, you *could* calculate an electricity vs gas cost comparison if you wanted to, but you're really looking for the cars energy input efficiency.

 

When looking at EV range (OP's question) it seems to make the most sense to look at the efficiency as reported by the car and not worry about charging losses.

When considering the costs then charging losses make more sense. This gets extra complicated if one charges at places with different prices.