cross-posted from: https://lemmy.world/post/22892955
The Prius Prime is a dual fuel vehicle, able to run 100% on Electric, or 100% on gasoline, or a computerized blend in-between. This presents me a great opportunity to be able to do a direct comparison with the same car of an EV engine vs an ICE engine.
Toyota computer claims 3.2mi-per-kwhr.
Kill-a-watt (https://en.wikipedia.org/wiki/Kill_A_Watt) claims 2.2mi-per-kwhr.
Additional 1.5% losses should be assumed in the wires if you wish. (120V drops down to 118V during charging, meaning 2V of the energy was lost due to the resistance of my home’s wires).
Level 1 charger at home (known to be less efficient).
Toyota computer claims 53miles-per-gallon (American Gallon).
I have not independently verified the gallon usage of my car.
295 miles driven total, sometimes EV, sometimes Gasoline, sometimes both.
30F to 40F (-1C to 4.5C) in my area this past week.
Winter-blend fuel.
12.5miles per $electricity-dollar (17.1c / kw-hr home charging costs)
17.1 miles per $gasoline-dollar ($3.10 per gallon last fillup).
If anyone has questions about my tests. The main takeaway is that L1 charging is so low in efficiency that gasoline in my area is cheaper than electricity. Obviously the price of gasoline and electricity varies significantly area-to-area, so feel free to use my numbers to calculate / simulate the costs in your area.
There is also substantial losses of efficiency due to cold weather, that is well acknowledged by the EV community. The Prius Prime (and most other EVs) will turn on a heater to keep the battery conditioned in the winter, spending precious electricity on battery-conditioning rather than miles. Gasoline engines do not have this problem and remain as efficient in the winter.
I originally wrote this post for /c/cars, but I feel like EVs come up often enough here on /c/technology that maybe you all would be interested in my tests as well.
Over in Sweden it would be hard to replicate these results. Gasoline is ~18SEK/l ($7.5 per gallon).
My electricity production cost changes by the hour, so I can steer my cost by charging when it’s costs are low. Taxes and transfer costs give me a minimum of about $0.07/kWh. A smart charger that picks when to charge based on price can probably average you a cost of $0.10/kWh over the year.
That’s crazy. Gas is less than half that in the US (<$3/gal in my area, just over $3/gal national average). If my gas was $7.50/gal, I’d definitely be driving electric.
Where I live gas is like 4.50, but electricity is also run by a for-profit company that the state doesn’t regulate.
I get £0.09 /kwh for overnight charging. I spend about a fifth as much on electricity for my car each month than I spent on petrol on my previous car.
Why does your car calculate your petrol efficiency but not your electrical efficiency? Sometimes hybrid cars are sold as being more fuel efficient, so report the fuel efficiency of the gas by including the electricity-fueled miles in when calculator the gas efficiency. (Toyota haven’t historically been terribly enthusiastic about electricity.)
My overall miles per gallon was 85mpg including electricity.
The 53mpg is within other tests (ex: consumer reports), and is within expectations.
Why does your car calculate your petrol efficiency but not your electrical efficiency?
On the contrary. I don’t trust Toyotas EV efficiency figure of 3.2mi/kwh because I’m measuring 2.2mi/kwh from the wall.
Are YOU measuring the electrical output from the wall correctly? The cars battery has a figure but it’s after the efficiency losses in the cable, heater and other such figures. My calculation includes all the losses except voltage sag in wires (1.5% estimate)
I’m calculating money I was charged by my electricity company actually during charging hours versus miles I actually drove. (The amount of electricity my house uses at that time of night is small and ignorable.) I’m trusting the milometer, but I think that’s reasonable. It isn’t claiming it’s further to work than my previous car did!
In any case, it was almost five times as expensive on petrol as it is on electricity in my usage, and even if you adjusted the figures slightly it wouldn’t make a difference. And the pure electric car is so much more fun to drive, with so much more oomph than any other car I ever drove. I love it.
I still think it’s weird that you’re not calculating your own gas efficiency. Toyota have a vested interest in you thinking they’re doing a great job of that. I don’t know why you’re trusting their figures for gas but you’re supremely skeptical about their figures for electricity. Why would they be so inconsistently honest with you, and why are you so inconsistently skeptical?
I still think it’s weird that you’re not calculating your own gas efficiency. Toyota have a vested interest in you thinking they’re doing a great job of that. I don’t know why you’re trusting their figures for gas but you’re supremely skeptical about their figures for electricity. Why would they be so inconsistently honest with you, and why are you so inconsistently skeptical?
You fucking serious mate?
Toyota figures are confirmed by consumer reports, car and driver, motor trend. Everyone is getting 50mpg even in the cold with the Prius.
The reason I’m not doing it personally is simple: it’s a 50mpg fucking vehicle. I need to drive 200miles to use 4 fucking gallons. That’s a long time to do a silly internet debate.
I’m going to do that eventually. But for fucks sake man, before criticizing my tests how about you think what the fuck I need to do to make effective tests here.
I’ll get a 200mi test done eventually. But not because you told me to do it. I always was planning on doing it but fuck man. You are a piece of shit for pushing this on me.
How about this. You go rent your own fucking car, spend 4 hours driving it and testing it and come back here so that I can shit on your results and tell you how you did it wrongly just because it doesn’t match my biases. Sound fair?
That escalated quickly!
As an outside observer, I was reading these posts calmly and under the impression it was a discussion between the both of you, then i read this comment, and the first line shocked me.
Where did all that rage come from?
Seriously, it was like maybe in the past an electic car slept with your wife.
All they said was they thought you might be biased, and you exploded. And what followed was you screaming at this person to take back what they said about you being biased whilst you insult and swear at them like they had walked into your house on christmas day and pissed on the kids.
Calm down, mate. It’s just a car.
I have a question about these dual fuel cars, gas has a shelf life and can mess up your engine if you let it sit for too long. Would this become an issue if you only make short, electric drives in the car?
The manual of mine specifically points this out and says that if you go three months without burning any fuel the engine will start being used until about a third of a tank is consumed.
Yes but there is an easy solution. Just fill up with 2 gallons, rather than 10 gallons.
Now you have the 100mi backup gasoline (why you bought a PHEV, right?), but still do EV every day. Every few months hit the HV button and burn off that fuel and fill up another 2 gallons.
That being said: Prius Prime dual mode has 0-60 time of 6.6 seconds. When both engines are on your acceleration is amazing, on both low end 0-30 EV) and high end (ICE engine covers 30-70mph).
So you want to be in auto mode (aka: use both engines mode) anyway for optimal driving experience.
And now that I know that gasoline is cheaper in the winter anyway, maybe I push that ‘use both engine’ button more…
If you ever need the 500mi gas tank for a long trip, just spend 5 minutes at a gas station. It’s not like our gas tanks are locked behind 20+ minute chargers or whatever.
Thanks for this. Are you planning to take more measurements during a warm season? It would be interesting to see how close the electric system comes to petrol in more favourable conditions/climates.
L2 charger at work returned 3.4mi/kwhr !!!
L2 charging at 50F (and below) is clearly way more efficient than L1 charging.
With this, I can safely say that L1 chargers should be avoided if possible.
