Featured Consumer Reports: The Most Fuel-Efficient Cars

But let's not forget that hybrid highway efficiency is usually quite a bit higher than conventional cars as well since hybrids have typically enabled use of Atkinson cycle engines.

 

Let's also not forget that the EPA city test is much slower than what many of us drive, and the highway test closer to a jaunt to the local big box store in suburbia than a modern highway run.

 

Don't forget that a number of traditional vehicles, albeit with variable valve timing to get some of the same Atkinson-like benefits, have greatly narrowed the gap on previous generation Prius highway MPG. The city MPG gap is more dramatic.

 

Anybody off the top of their head know what the best blended mpg is for a 5-seater? If I were to guess I would think maybe Chevy diesel Cruze. I'll bet it's too finicky to run off straight/filteted french fry grease
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Cruze Diesel, 37 MPG combined. 31 vity, 47 highway for automatic, 30/52 for manual turbo. Jag and BMW a single tick behind on the combined, but only 42-43 on their highway ratings.

For gassers, I no longer recognize all the hybrid names to weed them out. But Honda Fit and several others are at 36 combined, Mitsubishi Mirage at 37, there might be more up there.

For product liability reasons, virtually everything now is rated 5 seats unless the rear center is mechanically blocked. No matter how skinny and unrealistic that center is, some partying teens will still manage to shoehorn a fifth person in there. The fifth seatbelt is essential legal protection after the inevitable drunken crash. (I once owned the four-seater model that was hauled into court after a center-seated teen was fatally launched through the windshield.)

 

Personally, I only care about the overall fuel economy. I don't keep track of what percentage of time I'm driving "city" or "highway" and couldn't be bothered to figure it out. The only relevant statistic to me is overall because that's what determines how much gas I need to buy and how far the car goes before it needs more.

 

Do note that your driving mix is very unlikely to match the EPA's mix, so even the EPA Combined rating is likely to not produce a perfect ranking for your particular use pattern.

 

I'm on my third Prius, an '04, a '10, and a '16. For me highway mileage where I'm driving a steady speed always beats my city driving mileage. For me city driving is stop and go with either stop signs or lights about every 200 - 300 feet on average and speed limit is 30 - 40 MPH. Highway mileage is usually mid-50s while city is often about 49 - 50.

 

I drive a Prius v and my 38k MPG is spot on what EPA combined is.

My guess is 95% of my trips are within 10 miles one way city mix in all sorts of conditions from 15F to 102F with all sorts of gas, another 4% are 50 miles one way at 55 to 70 MPH and only 1% are 150 miles or longer at highway 65-70 speeds. I use no special techniques unlike Wayne. My highway long distance runs at 65-70 MPH are within 1 MPG of EPA. I'm right in the center of the bell curve at fuelly. My first hybrid but I don't see EPA's techniques misleading me. Nor when I look at fuelly for other cars I might be interested in do I see fuelly numbers much different than EPAs.

 

Bob was referring to the EPA ratings, which are rather artificial. That doesn't really apply to the actual results for very many drivers.

The EPA City and Highway label ratings have empirical fudge factors to derate the numbers from the actual dyno measurements. However, the applied factors are greatly different -- big derating for highway, small for city -- so the fact that these cars have higher city ratings than highway ratings, becomes a bit of a meaningless artifact. Many real drivers in real conditions just won't see the same phenomenon.

 

I don't think any modern diesel can stomach straight vegetable oil in any quantity. There is more emission control equipment and the fuel systems are running at higher pressures. The manufacturers are also in cover their nice person mode in regards to biodiesel concentration, because they have no control over homebrew quality.

GM and Ford do allow B20 in their diesels however, which is a big step over the B5 of the Europeans.

Then from the drivers' perspective, much of what they think of as city driving is closer to highway by the test cycles.

 

According to fueleconomy.gov, the highest conventional gasoline EPA highway estimates are 43 mpg for the Mitsubishi Mirage, 42 mpg for the Honda Civic, and 41 mpg for several cars, etc etc.

For hybrids, the highest highway gasoline EPA is 59 mpg for the Ioniq Blue, 54 mpg for the regular Ioniq, 53 mpg for the Prius Eco, 50 mpg for the regular Prius.

The lowest hybrid highway mpg goes to the Ferrari LaFerrari Aperta super car at 15 mpg but it's a mere "mild" hybrid. The lowest full hybrid is the Lexus LS 600h sedan at 23 mpg.