With 15 miles of electric charge in the battery pack, Jan and I on a recent cold evening guided the 2018 Kia Niro Plug-in Hybrid 55 miles “round the block.” The big block was from Greeley west to Loveland, north to Fort Collins, east to Ault and south back to Greeley.

Judicious use of the limited electric charge, mostly on the slower pace on Colo. 14 from Fort
Collins to Ault, helped the Niro post an average of 49.2 miles per gallon for the drive. I opted for gasoline power along the 75-miles-per-hour stretch of I-25 from Loveland to Fort Collins. On the last leg south from Ault, I engaged the Sport mode, which improved on the slow acceleration in the default Eco mode.

Numbers of models of gas/electric hybrids, plug-in hybrids and battery electric automobiles are approaching 90, boosted by increased promotion and attention; still their total sales in 2017 accounted for only 3.2 percent of the light-duty vehicle sales in the U.S.

Arrival over the past month of the Niro Plug-in Hybrid follows introduction last year of the Niro’s regular gas/electric hybrid, which was fourth-best-selling hybrid for the entire year of 2017, yet was on the full market for only slightly more than six months.

With a battery pack tucked beneath the cargo area, the new plug-in version has a range of 26 miles on electricity before the gas engine kicks in, according to Kia estimates. Its battery pack can be recharged overnight from a 120-volt electrical outlet.

Its powertrain consists of a 60-horsepower electric motor rated at 45 kilowatts, a 103-hp, 1.6-liter 4-cylinder gas engine and 6-speed dual-clutch automatic transmission, which outperforms most continuously variable transmissions used in some other competitors

Sticker price on the Niro Plug-in Premium was $35,575, about $5,000 higher than the Niro gas/electric hybrid I  tested last May.

The all-time sales leader among gas/electric hybrids, the Toyota Prius Liftback, suffered a 17 percent decline in sales during the past year; causes seem to be continued low fuel prices and greater choice of competitive hybrid models.

The Prius Liftback has led sales of gas/electric hybrids since it was introduced in 2000. Its stablemate, the Toyota Prius Prime led sales of plug-in hybrids and the Tesla Model S was top-selling battery electric model.

Enjoying the hottest sales paces at yearend are the Kia Niro and Ford Fusion among hybrids, the new Honda Clarity among plug-ins and the Chevy Bolt among battery electrics.

Sales of hybrids, plug-ins and electrics for the year were 558,653, compared with 504,207 in 2016.

The top 10 sellers in 2017 for the three categories are:

HYBRIDS

Toyota Prius Liftback 65,631; Ford Fusion 57,474; Toyota RAV4 50,559; Kia Niro 27,237; Honda Accord 22,008; Toyota Camry 20,985; Toyota Highlander 16,864; Toyota Prius C 12,415; Hyundai Ioniq 10,765; Ford C-Max 10,250.

PLUG-IN HYBRIDS

Toyota Prius Prime 20,936; Chevrolet Volt 20,349; Ford Fusion Energi 9,632; Ford C-Max Energi 8,140; BMW X5 5,349; BMW 3-series 4,141; BMW 5-series 3,772; Chrysler Pacifica 2,981; Audi A3 2,877; Volvo XC90 2,228.

BATTERY ELECTRICS

Tesla Model S 26,500; Chevrolet Bolt EV 23,297; Tesla Model X 21,700; Nissan Leaf 11,230; BMW i3 6,276; VW e-Golf 3,534; Fiat 500e 3,336; Kia Soul EV 2,157; Ford Focus EV 1,817; Tesla Model 3 1,770.