U.S. sales of cars with plugs were essentially flat last month, as low gas prices and perhaps anticipation of longer-range entries within months kept a lid on buyer interest.

The second-generation Chevy Volt plug-in hybrid, now available throughout the country as a 2017 model, logged 1,901 deliveries in May, for a year-to-date total of 7,871.

That's respectable, though hardly a barn-burning pace. Nor is it near the Volt's best-ever month of August 2013, when 3,351 were sold.

DON'T MISS: Plug-in Electric Car Sales in Canada, May 2016: Canada crosses 20,000 cars with plugs

At least the new Volt is holding its own, however.

Its five-year competitor, the battery-electric Nissan Leaf, continues to languish in the market despite a range boost from 84 to 107 miles for the 2016 model year.

Just 979 Leafs were delivered last month, for a year-to-date total of 4,697—far below its pace even last year.

2016 Nissan Leaf

2016 Nissan Leaf

The BMW i3 logged 696 sales in May, for a five-month total of 2,272.

That would be surprising for a car that sold more than 11,000 units last year, except that a 114-mile version for 2017 will hit dealerships this fall (up from the current 81 miles).

Finally, because Tesla Motors refuses to release monthly sales data or break out its sales by region, we don't know how many Model S sedans and Model X crossover utility vehicles were sold.

CHECK OUT: U.S. Plug-In Electric Car Sales For 2015 Fell Slightly From 2014

Tesla said over the weekend that it was now building 2,000 or more electric cars each week, but that production is split among North America, Europe, China, and other markets.

Sales of the Volkswagen e-Golf have lagged this year compared to their pace at the end of 2015.

May deliveries were 269 units, for a five-month total of 1,207 electric Golf hatchbacks.

2016 Ford Fusion Energi

2016 Ford Fusion Energi

Plug-in hybrids

Ford continues to sell roughly 2,000 plug-in hybrids a month, and as usual, the Fusion Energi mid-size sedan handily beats the C-Max Energi compact tall hatchback.

The plug-in hybrid C-Max found 538 buyers, against 1,453 for the larger Fusion plug-in, with their five-month totals reflecting the discrepancy at 2,595 and 5,535 respectively.

ALSO SEE: 2016 Tesla Model X first drive review

That total puts Ford just slightly ahead of GM in plug-in hybrids (though GM comes out on top when the two makers' all-electric compliance cars are added in).

Ford Focus Electric sales in May were 54, for a 2016-to-date total of 392, versus 394 Chevy Spark EV sales, for a total of 1,420 over five months.

The electric Focus will get a range boost to more than 100 miles by the end of the year, while the 2017 Chevrolet Bolt EV with 200 miles of range goes on sale by then as well.

2016 Audi A3 e-Tron Sportback, San Francisco Bay Area, Oct 2015

2016 Audi A3 e-Tron Sportback, San Francisco Bay Area, Oct 2015

Sales of the Audi A3 e-tron plug-in hybrid hatchback were 361 in May, for a year-to-date total of 1,589—a higher total, it's worth noting, than for its corporate and product sibling the Volkswagen e-Golf.

And another 4 remaining Toyota Prius Plug-In Hybrids found buyers, though its sales have been dwindling since last summer, when it was taken out of production.

Its successor, the 2017 Toyota Prius Prime with 22 miles of electric range, will arrive at dealerships this fall.

Low-volume vehicles

Among the vehicles that sell only in small numbers, another 2 Mitsubishi i-MiEVs found buyers, for a year-to-date total of just 16 of the tiny, aged electric minicar.

2016 Smart Fortwo Electric Drive

2016 Smart Fortwo Electric Drive

The Smart ForTwo Electric Drive logged 75 deliveries, for 313 so far this year.

It will be replaced within the year by an updated electric variant based on the new 2016 ForTwo that's already on sale; that new electric Smart should debut at this fall's Paris Motor Show.

The Mercedes-Benz B250e (aka B-Class Electric Drive) saw deliveries of 49 more units, bringing the year's total so far to 266 of the battery-electric small hatchback.

2016 Cadillac ELR

2016 Cadillac ELR

Among low-volume plug-in hybrids, the now-officially-defunct Cadillac ELR saw 45 deliveries (402 for the year-to-date).

The BMW i8 gull-wing coupe racked up 146 in May, its best since last year, bringing its five-month total to 451—and continuing its record of trouncing Cadillac's hapless plug-in luxury coupe.

Porsche continued to deliver its E-Hybrid variants of the Cayenne utility vehicle and Panamera large sport sedan, with 191 and 26 respectively delivered in May.

Year-to-date totals are thus 990 and 134 respectively, which make up 5 percent of Porsche's five-month U.S. sales of 22,226 vehicles of all types.

Volvo sold 110 of its XC90 T8 'Twin Engine' plug-in hybrid SUVs, its lowest number in five months, bringing the five-month total to 840—or 3 percent of its 28,066 sales this year.

2016 Volvo XC90 T8 'Twin Engine' plug-in hybrid, Spain, Feb 2015

2016 Volvo XC90 T8 'Twin Engine' plug-in hybrid, Spain, Feb 2015

The plug-in hybrid S-Class Mercedes, however, has lagged this year. After a two-month hiatus, 3 were delivered in May, for a 2016 total of only 41.

We'll add figures for the BMW X5 xDrive 40e plug-in hybrid SUV and the Hyundai Sonata Plug-In Hybrid when we get them.

Finally, the makers of the Fiat 500e electric minicar and the Kia Soul EV electric tall hatchback also refuse to release their monthly sales figures, or break the totals out from the broader model line.

And a handful of plug-in vehicles are now effectively off the market, including the Honda Accord Plug-In Hybrid, the Honda Fit EV, and the Toyota RAV4 EV.

All of them could fairly be considered compliance cars that have met their legal minimums and are of no further use to their makers.


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