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

There are many ways to look at the charging speeds. I don't want a "better inverter (SIC)" though I suspect you meant charger. I want my charger to be matched to the system that it is working in. The Toyota Prius Prime battery is fairly small, and the charging circuit appears to charge it quickly enough as is. Doubling the amps during charging can be a bad thing, as exemplified by the Tesla warnings about using their fast supercharger service too frequently because it degrades the battery.

You'll probably notice that the Rav4 Prime has twice the battery capacity (compared to the Prius) , and allows higher charging rates as a result.

 

Is it correct that the car built-in charger to determine the max amp it takes?
If that's the case, I assume that is perfectly fine to use 32 amp level 2 to charge our PP since max am it takes is 16.
Pls correct me if I am wrong

 

That is correct. The charger is in the car and the charger sets the max charge rate, assuming the circuit powering the EVSE can provide the amps necessary for that charge rate. In the car's preferences, you can select 8 or 16A as the max charge rate. That's in case you're plugging into an outlet that's on a circuit with something else running so you don't trip the circuit breaker.

 

I think your facts are correct. However, the fact that the Rav4 Prime has a higher charging rate is not a "result" due to the larger battery size but rather a design choice made by Toyota.

Mike

 

It's quite possible that you are right Mike. According to Toyota's web site, The provided Rav4 charger is for use with a 120V outlet at 12 volts.

It sounds like they chose to provide the 6.6 kW charger as an option for the Rave4 Prime.

The charger on my Prius Prime pulls about 16 amps at 240V at my home and charges in a touch over 2 hours if it's ever depleted. Funny thing is, that I've never needed to use a 3rd party charging station. Before covid, I used gas on long interstate trips and my daily driving almost never depleted the battery. By almost never, I mean two or three times in a year.

This is a related topic, and the consensus was that the battery in the PRIUS Prime was not designed for charging at 6.6 kW.

 

Right here, right now, (Quebec city) electricity is like 8.9xyz cents per kwh. Car will take 6.2kwh when "empty". Let's say price is 10cents to make it easy and also account to some ineficiency between outlet, charger box, in car charger, other what's not, and you have a 62 cents charge that gives you more or less 50km of EV autonomy. Gas is 1.459$ PER LITER. You wont do 50km with more or less 400ml of gas... EV wins!

Now give me more electric autonomy.

 

Are those prices in $CDN? Translated to $US, that is dirt cheap electricity by U.S. standards (hydro is good for that) but expensive gasoline. Well, except for California, where that gas price is about the current average.

 

Canadian currency yes. And yes electricity is cheap here (but let's not say it just in case someone at Hydro Québec sees that... ) and gas is effin' expensive. I have tears when i have to fill the Si.. Premium is more or less 1.669$$ per liter here... Fortunately the Prime runs on regular and we have free level 2 chargers at work for employees!! (Ftw!)

 

Converting to US$, your electricity rate US$0.07 is one-third of the cost of mine US$0.21/kWh (US average is ~$0.12/kWh). While your gas price conversion is US$4.37/gal which is 46% higher than our current local price of $3/gal (the current US average is $3.188/gal). Of course, EV wins in your area. In our area, the break-even price of gas (considering no change in the electricity rate) is $2.85/gal. I have owned PP since mid-2017, but the last few months are the first time gas price is higher than electricity. Right now, I try to drive as much of my driving on EV mode as possible with frequent charges, but if the price of the gas goes below $2.50/gal again, then I will be doing most of the drive on HV.

 

21-cents per kWh is also the rate here in eastern Massachusetts. And I totally agree with your numbers showing $2.85/gal to be the break-even point at that electric rate. Right now the "fuel guide" on my cellphone Entune app shows most gas stations in my area changing $3.10 to $3.20 per gallon with our nearby Costco charging $2.90.

Generally speaking, the difference in cost between electricity and gasoline has been negligible in the four years we've owned our Prime. At the moment, EV wins which is a nice feeling because we drive almost totally in EV just because it feels nice and it's better environmentally.

Now if we could make use of some of that inexpensive Quebec hydro power, the choice would be even easier. But so far, our neighbors to the north in New Hampshire and Maine have been strongly opposed to the construction of a planned high-voltage transmission line. I guess we each can claim to be good stewards of the environment in our own way.

 

Well maybe there could be a way that Massachussets could tap thru that new underground New York power line? I honestly wishes that happens for you my southern friends!

 

This is a nice discussion and the original graphic is a neat idea, but the rates don't at all seem to apply in the real world where we live. Here are the current residential EV rates in PG&E territory:

 

Charging elw electric costs more than the price per kW. You have to deduct the added cost for the car and divide it over it's 200k mi lifecycle, then add that fractional increased purchase price to the charging cost

 

Your electricity is quite expensive. Here, there are only two costs. One for the first 2,400 kWh consumed within the billing period (60 days) and another for anything above that 2,400 kWh. The first one is 7.5¢ per kWh and the second is 10.5¢ per kWh. The only other fee is a 21¢ per day for network access and taxes. No other charges.

 

Yep , keep in mind the currency exchange from CDN to USD ..this add a greater difference between energy cost 35% difference

 

Yeah, it would be like Americans paying 5.5¢ per kWh.

 

In my state, east of the mountains, the Chelan County PUD is charging a residential rate of just US 2.7¢ per kWh. It serves a low population county bordering the Columbia River, and has first claims on two of the Columbia's hydroelectric dams.

A few other counties with similar circumstances are paying in the 4 to 5¢ range, while most of the rest of us in this hydro-rich state are paying above 10¢.

 

Lucky, 100% of our local areas needs are technically served by the hydro dams but the utility and state approved 3 fossil fuel plants in the area to bolster utility profits.

100% of our fossil fuel power is exported but we still get to pay dearly for the privilege of making other people’s pollution and power.

The fixed fees went from $9.99 a month to $49.99 a month in a relatively short time, similarly our rate went from 9 cents to 14 cents a kwhr in a short time. Off peak went from 1 cent to 6.6 cents (slated to increase soon) as nuclear and hydro was decommissioned.

The solar buildouts are slated to increase these costs further.

And all of it unnecessary because we already had all of our needs covered by hydro and nuclear, instead we get to increase bills further to pay for the removal of “unnecessary “ hydro and nuclear

lots of boneheaded decisions.

Similar to the recent completion of one of Canada’s oil pipelines that instead of lowering oil costs raises fuel prices in the Midwest giving Canada access to export all its oil overseas.

 

Does that includes all the cost? For example, in Ontario, under ULO with its cost as low as 2.8¢ per kWh, you still have to add delivery/distribution/transmission charges, the loss adjustment factor, and HST, which bring it closer to 7¢ or 8¢ per kWh.

 

I really wish I could get the US average rate... Just received a notice that our utility is asking for a rate hike again for next year. It is currently $0.32/kWh... way off the chart of the OP graph on comment #1. Will be a 10% increase, so expecting $0.35/kWh next year. Our community solar is not a much help in winter... I got a 10kWh production share this month. LOL