Hyundai is known in the auto industry as an aggressive and very capable competitor, and the world's largest makers watch it closely and take it very seriously.

The company didn't introduce its first hybrid car in the U.S. until 2011 and, frankly, that year's hybrid Sonata sedan wasn't very good.

Just six model years later, the company's hybrids are much improved and it has launched a world first: a car that can be ordered with hybrid, all-electric, or plug-in hybrid powertrains.

DON'T MISS: 2017 Hyundai Ioniq Hybrid: gas mileage review

That car is the Hyundai Ioniq lineup, which for 2018 will see a plug-in hybrid version join last year's hybrid and electric models as its third and final member.

The full Ioniq range is one of our three finalists for the Green Car Reports Best Car To Buy 2018 award, and its diversity is one of the reasons.

Many automakers spout marketing messages about offering consumers "choice" in green cars, but that generally means one conventional hybrid option along with a variety of efficient and not-so-efficient gasoline engines.

2017 Hyundai Ioniq Electric

2017 Hyundai Ioniq Electric

The Ioniq is different, and the 2017 Ioniq Blue Hybrid has the highest fuel-economy rating on the market, at 58 mpg combined, beating the Toyota Prius Two Eco by 2 mpg combined.

Reviewers have generally lauded the Ioniq for its relatively conventional styling (especially against the polarizing Prius, ahem), straightforward and intuitive interior and controls, and driving character.

But while the Ioniq Hybrid will sell in the highest volumes, the Ioniq Electric with its 124-mile EPA-rated battery range has its own charms.

WATCH THIS: 2017 Hyundai Ioniq Electric: video review of 124-mile electric car

The battery-electric Ioniq is not only the smoothest, quietest, and most comfortable version, it's the most energy-efficient car sold in the U.S.—beating both the technically sophisticated BMW i3 and the plug-in hybrid Toyota Prius Prime.

Hyundai takes pains to note that while the electric Ioniq is marketed only in the handful of states most receptive to buying cars with plugs, it can be ordered anywhere in the country through any Hyundai dealer.

It's also leased via the "Unlimited+" program, a plan that mimics a subscription service, and adds unlimited mileage allowance, vehicle-charging reimbursement, and a cohesive maintenance plan to the standard lease term

2017 Hyundai Ioniq Electric (European spec), 2016 Geneva Motor Show

2017 Hyundai Ioniq Electric (European spec), 2016 Geneva Motor Show

The plug-in hybrid Ioniq, to arrive as a 2018 model, will offer an estimated 27 miles of range, toward the top of the list among plug-in hybrids. It could rank fourth after the BMW i3 REx (97 miles), Chevrolet Volt (53 miles), and Honda Clarity Plug-In (47 miles).

Its powertrain is essentially carried over from the conventional Kia Niro hybrid, with a 103-horsepower 1.6-liter 4-cylinder engine and 6-speed dual-clutch automatic-shifting gearbox sandwiching the electric motor.

That motor is rated at 45 kilowatts (60 hp), slightly more powerful than the 32-kw (43-hp) motor used in the regular hybrid. An 8.9-kilowatt-hour battery pack is tucked under the rear seat and cargo bay.

CHECK OUT: Hyundai Ioniqs: pitting hybrid vs electric on video

Final EPA ratings for the plug-in Ioniq's electric range and energy efficiency will be released when it goes on sale at the end of this year or the start of 2018.

Hyundai has said it intends to sell more green cars globally—meaning hybrids, battery-electrics, plug-in hybrids, and hydrogen fuel-cell vehicles—than any other maker than Toyota by 2020.

Its competitors have every reason to believe that, and the Ioniq represents an ambitious foray into high-volume, fuel-efficient vehicles.

2018 Hyundai Ioniq

2018 Hyundai Ioniq

2017 Hyundai Ioniq Hybrid

2017 Hyundai Ioniq Hybrid

2017 Hyundai Ioniq Hybrid

2017 Hyundai Ioniq Hybrid

Over the 10 months ending in October, Hyundai delivered only 9,327 Ioniqs in the U.S., though it has not broken out the number of hybrid and electric variants. That's just one-tenth the 91,031 Prius models, of four different varieties, sold over the same period.

The Hyundai Ioniq range, which we tend to describe as green, greener, and greenest, is a new and ambitious entry into a tough market facing cheap gas prices.

Its efficiency and generally attractive personality make it an unquestioned finalist for our Best Car To Buy 2018 award.


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