This article brings up two questions.

1) I am interested in how much 80 cents (CDN)/Litre equals

2) What kind of ratings have the canadian "energuide" folks given comparative to the EPAs FE ratings.

It looks like for the prius they say 63/60. How does that relate to the EPAs mpg for the Prius?

 

Well, Canadian dollar is worth about $0.81 cents US right now, and gas here costs about $1/L.

1 US gallon = 3.7854118 liters

So, we pay about $3.79 Canadian a gallon, or $3.07 US a gallon.

Still too cheap.

 

US EPA rating for the 2004/5 prius is 51 hwy/60 city.

Some of the other ratings seem somewhat inflated over the US ratings too, for example they list the ford focus at 33/47 (US 26/35).

 

Actually, accelerating and braking hard with hybrids is *good*. It's been demonstrated that gentle acceleration is worse for overall mileage than accelerating hard and then maintaining the fixed speed. And braking is regenerative anyway, although admittedly hard braking also uses regular brakes, whereas gentle braking would mostly be regenerative.

But as someone who grew up in New York, I can tell you taxis, like everyone else, spend most of their time stationary. Hybrids were designed for city environments and it's just dumb for taxi companies not to buy them. They'll save themselves so much money.

 

from my limited amount of taxi riding experience, there is a big difference between accelerating at a moderate rate and flooring it. also, a difference between braking and coming to a complete stop within 5 feet. I dont disagree that they would be beneficial, I just wonder how much?

I still stand by my point that it cant be a bad way to stress test the vehicles, in more ways than one.

 

Flooring it *is* accelerating at a moderate rate in current hybrids, besides maybe the Accord. Just remember the Prius was originally designed for driving in Japan's cities, and it's at least as bad there as NYC. City driving is where hybrids excel. Also, keep in mind taxis run for a very long time, so you don't have the issue of the engine being inefficient while it gets warmed up.

And, as I said, taxis spend most of their time stationary in NYC (Manhattan, at least). Either the light is red, there's traffic, or they're picking up or dropping off fares.

Anyway, in my experience they don't actually brake or accelerate particularly hard, since traffic doesn't move that quickly anyway. They steer hard, without blinkers, but that's irrelevant.

 

I've read of people running tests on the FE of acceleration, and they actually found the exact opposite. Gentle acceleration used less gas in all cases, and this would be even more pronounced in a full hybrid because of the extreme efficiency of the electric motor at low speeds. I think we're dealing with a persistent automotive myth, unless there are some studies that show otherwise...

 

Obviously accelerating gently uses less gas than accelerating hard. I didn't argue against that. What I stated was that the former was worse for *overall* mileage. If you accelerate gently, you will be doing so for a longer period of time than if you accelerate hard to quickly reach cruising speed. And remaining at a fixed speed is very good for fuel efficiency.

So you might enjoy accelerating slowly and seeing your current FE indicator stay at 40mpg, even though you cruise at 50mpg... but if you just spent two seconds accelerating quickly at 20mpg, quickly reaching cruising speed at 50mpg, you will find you got better total mileage using the quick-acceleration method, according to what I have read. I haven't been able to see this myself however as I don't yet have my own hybrid; this is just third-hand knowledge. Also this was specifically about Priuses.

 

The thing is, when you accelerate hard it's not 20MPG, it's closer to 5MPG, and worse in cars with bigger engines than the Prius. I've found average fuel consumption drops when I accelerate gently, not rise. I understand what you are saying and I used to think the same thing, but now it's not so clear. The amount of energy a car uses to get up to speed is proportional, but exponential to the rate of acceleration, so the faster you boot it, the more energy you are using for the distance you travelled. You'll get ok FE if you use brisk acceleration, but to maximize FE you'll need to use gentle acceleration. Non eCVT type cars will also pollute a lot more during hard acceleration because they need to burn rich to get the torque at lower RPMs, so from an emissions point of view it's also better to use gentle acceleration.

Drivers in our area seem to believe that it's best to accelerate as fast as their car can go, so it doesn't really matter much if you're keeping up with traffic you'll be accelerating hard anyway, but I'm pretty sure (from my own experience) that gentle acceleration is much better overall than brisk acceleration, at least in our Prius I and my friend's Prius II.

 

Perhaps I'm mistaken. Certainly, theoretically, gentle acceleration should be more fuel-efficient, but then theoretically not moving should use no fuel, yet nearly all cars use quite a bit of fuel while remaining stationary. It all depends on how the car is designed. I can see how a car could be less fuel-efficient when accelerating gently if it uses the ICE more than it needs to, just because of the fact that the car is accelerating. But maybe current hybrids are more intelligent than that.