Gas, diesel, hybrid, or electric? Everyone
wants their next car to have better fuel economy and wouldn’t mind if it’s
better for the environment. But which engine is the right choice? Ultimately,
it depends on the kind of driving you do and how much distance you’ll travel
before turning the car over to the next owner. This auto tech backgrounder will
help you decide which engine is best, given your circumstances.
Here’s the broad answer: Go with gasoline if
you’re a low-mileage driver, hybrid for city driving, and diesel for
high-mileage (mostly highway) driving.
The mainstream gasoline engine is best if you
drive less than 7500 miles a year because the savings on fuel won’t match the
premium you’re likely to pay for a hybrid or diesel car. Hybrid
is the winner if you cover a lot of miles in stop and go city driving or on
clogged expressways, where braking recharges the battery that powers the
electric motor. It helps if you’re easy on the throttle and brake early and
smoothly in a hybrid.
If you drive a lot of highway miles, diesel
cars — like the 2014 Chevy Cruze diesel — are right choice for
cost per mile driven, and most diesel vehicles have higher trade-in values than
gasoline-powered cars. The case for diesel is clearer in the premium/sporty
segment where the gasoline engine uses premium fuel, so the diesel price
disadvantage per gallon of fuel is less than 10%.
To draw the conclusions above, you need to
think about a half-dozen factors and how your driving fits in. Higher
miles-per-gallon is just part of the picture. The more miles you drive, the
sooner you get payback. The residual value of your ride may tip the scales.
Diesel or hybrid price
premium
Start your gas-hybrid-diesel calculations with
the price premium for a hybrid or diesel car over the most similar gasoline
car. It ranges from nothing on Lincoln hybrids to $5000 on pickup trucks with
heavy duty diesels. A $2000 diesel or hybrid premium is a good starting point for
your comparison. If a diesel car has 200,000 miles of life in it (that kind of
lifespan is easy for a diesel), that’s a penny a mile you have to recapture.
You have to decide whether the proper
comparison is the gasoline car with the closest 0-60 mph acceleration or best
fuel economy, which will probably be the entry-level gasoline car with the
smallest engine and lower price; or the car with the same level of amenities.
Finding an apples to apples comparison is tricky. For example, a hybrid more
often comes standard with navigation worth $500-$1500 on the sticker price
because the automaker wants to provide a center stack color LCD display to show
of all the efficiency-monitoring graphics, and the cost puts you halfway toward
that of a navigation system.
The price premium for an electric vehicle is
significant. The best is the Chevrolet Spark EV at about $5000 more than the
comparably equipped than the gasoline Spark.
Residual value may be better
with diesels, hybrids.
A diesel vehicle will be worth more than the
average vehicle at trade-in time. A hybrid should at least match the residual
value of the gas engine car. For EVs, which sell in smaller numbers, the
residual value may depend on each model’s reputation and on the length of the
battery warranty; the battery is often half the value of the vehicle.
The average vehicle retains 38.2% of its value
after five years (37.2% cars, 39.8% light trucks), according to kbb.com, measured as a percentage of the list
(sticker) price. The 2013 Ford Fusion does the best job retaining value
among hybrids at 45% after five years, but that’s still outside the top 10 gas
engine vehicles. Fifteen years of hybrid sales in the US shows little evidence
the $2,500 batteries wear out but rapid improvements in hybrid technology mean
a used hybrid feels more geriatric that a gasoline car. The best EV for
residual value, kbb.com says, is the Chevrolet Volt (really more of an
extended-range hybrid), retaining 30.0% of its value at five years.
For many hybrid cars where the model has a
gasoline counterpart (Ford Fusion, Honda Civic, Hyundai Sonata, Nissan Altima),
the residual value of the two cars are often the same or within 1-2 percentage
points of each other.
Nine of 10 diesel cars and trucks studied by
the University of Michigan had better five-year residual value than their
gas-engine counterparts and half were at least 10 percentage points better, led
by the Mercedes-Benz GL with a 39% residual value
advantage over the gas GL. It is also our favorite full-size SUV. What’s more,
with the GL, the diesel version is the cheapest GL model.
If you lease rather than buy, you should get a
lower lease payment with diesel than gas. A car lease is a loan of 24 to 60
months on the difference between the price new and the value used (that and the
“acquisition fees” auto dealers love). A lease on a high-residual-value diesel
lets you buy more car for the same monthly payment, give or take the diesel
premium. But if you buy, you’re financing, say, a $32,000 vehicle rather than
$30,000 (the average new car cost). You’ll get most of it back a couple years
down the road.
