Gas or Electric: Which one is cheaper for the Prius Prime!

For US folks, Google says that 1 C$ / liter =2.92006665 US$ / US gallon

 

I think he has posted that spreadsheet somewhere here. I can't find the thread now, but I do have a copy of the file I downloaded over a year ago.

 

I adopted that same spreadsheet and played around with the inputs and formulas on the left half. I see no need for that big block on the right.

 

If you go to this link there is a detailed method describing the calculations. Using the method detailed $CDN= 1 and an exchange rate of $.75 the price is currently $2.84.

My current price is $0.89 Canadian

here's to wishing for a 'delete' button

 

How do you test your tailpipe?

 

I did not see it mentioned in this thread, but to figure out kWh cost, take the total monthly bill divided by kWh used. That way you catch the delivery, taxes, fees and supplemental charges. For solar owners take the system cost after credits and rebates and divide by 20 (years). Add monthly service charge times 12 to the cost per year. Then divide that by kWh produced per year.

 

Having just filled my tank at $1.45/ gallon, I have stopped charging my Prius for now.
It doesn't make sense @ ~ $.20 / kwh.

 

other than pollution

 

And keeping us from needing to import the marginal extra barrels, taking away income from OPEC

 

In my state (MA) 67% of electricity is produced by natural gas power plants. Due to a shortage of pipe line
capacity, much of the natural gas must be brought in via tanker ships, that burn bunker fuel in the process.
Also, there is significant loss of available power during the transmission process.

Solar panels are not a perfect solution, there have been several electrical fires caused by solar panels in the past
year in MA (20 in one year as I recall, I can probably locate the article from a local TV station).
I also have concerns about roof leaks especially once these systems have been exposed to the weather
for several years. More holes in a roof means more chances to have a leak.

 

We recently had Nor'easter hit our area and lost electricity for 24 hours. Our 7500W back-up generator burned almost 16 gallons of gas in 24 hours. Even at historical low price of gas at $1.47/gal in our area, that's $23/day for electricity. Using gasoline to generate electricity is almost 3 times more expensive than getting it from the grid at $0.21/kWh.

No, I did not charge PRIME with the generator.

 

I'm not seeing the point concerning a generator. When I first got my prime, as I recall, the break even point
with a 110 v charge was ~$3.00 / gallon, at my cost of $.20 / kwh.

The range on a charge varies, I get a range of 22 miles on a charge in cold weather, and up to 34
miles in warm weather, but when gas is less than $2.00, it is definitely cheaper to use gasoline.
BTW I'm seeing $1.37 / gallon now.

An interesting observation is that in Eastern MA some municipalities furnish electrical service at
a cost of ~ $.16 / kwh, from what I've seen. It also seems that they are better at restoring service
after a storm.

 

The point is that even though I and you both live in areas of the country with high electric rate ~$0.21/kWh compared to the national average of ~$0.12/kWh, the electricity from the grid is still far cheaper than what can be generated from a regular gas engine generator.

As you pointed out, Prime gas engine used to propel the car is extremely efficient. Yes, if you want to save money at current gas price, it makes no sense to charge PRIME and drive on EV mode only. But, saving is only a few cents/mile. I have not been driving much lately with stay-at-home order in place, but when I drive occasionally for essential activities, I still prefer to use EV mode for a short trip to avoid the visit to a gas station for foreseeable future. At least until all the threat from COVID-19 is gone.

 

Yes generators are not very efficient, but very nice to have in a power outage.

If I was "confined to quarters" as many are these days, I agree that charging would be a good way to avoid contact /possible infection.
I have always kept sanitizing wipes in my car and used them after pumping gas (as well as other times).

Now, my supply and replacement sources of such items is limited. I use the bag that the WSJ comes in as a glove when I go to the gas station.

I still am out and about, I guess I'm essential (the state says I am), I put over 100 miles on my Prius one day last week - all business activity.

 

i love these graphs. but not being PHEV knowledgeable I need to know what the 2020 prime prime gets in miles/kwH so I can draw my axis points correctly. my electricity rate is .175 and gas is $2.00 a gallon.

 

In addition to the daily or monthly number mentioned by @Tideland Prius You can also see the lifetime overall miles/kWh on MID Drive Monitor 2. This number is for a lifetime if you have not reset it.

In the pic below from my 2020 PRIME, 22.2 miles/kWh is my lifetime EV efficiency over 1289miles of the drive. But this is a very unusual number. I drive my car in EV mode very sparingly to conserve my traction battery SoC. Most people have something in between 4miles/kWh to 6miles/kWh.

 

Although the Salamander King is in the rural north of Maine and I am in Boston, we both deal with $0.21/kWh electric rates.

For the month of August, I drove 324 miles and used 72kWh of electricity as measured by a watt-hour meter on the EVSE circuit in my garage. Usually I will use a free Chargepoint public charging station one or twice a month, but in August I did not. So my numbers are a good measurement.

72kWh of electricity from the grid at $0.21/kWh cost $15.12. So that works out to about $0.047 per mile. Typical gasoline prices in the area are $2.04 to $2.15 per gallon. Costco member price is currently $1.90 per gallon.

So, at $1.90 per gallon, I could have bought 7.96 gallons of Costco gas. And, to drive 324 miles, I would have needed to average 40.7 mpg which is not an unreasonable figure for the Prius Prime in urban driving.

(At $2.15 per gallon, I would have needed to average 46 mpg, which might be possible but not likely given urban start-and-stop short trip driving.)

My conclusion is that there's not much difference in cost of gasoline vs. electric driving given the price per gallon and per kWh for energy in my area. And this is more or less consistent with what I've observed for the three years I've owned my Prime.

Obviously, if you live in an area with higher gas prices and lower electric rates, your situation will be different.

As for myself, I agree with Salamander King that the benefit is the pleasure of electric driving and not any meaningful cost savings.