With the Labor Day holiday imminent--falling well into September this year--industry analysts have expected U.S. new-car sales for August to be less buoyant than they might otherwise be.

But in the lower-volume world of plug-in electric cars, model cycles remain the driving factor.

The first-generation Chevy Volt has been on a long sell-down, and next year's Nissan Leaf--widely expected to offer a longer-range battery--hasn't yet been released.

DON'T MISS: Will 2015 Plug-In Electric Car Sales Exceed Last Year's Total?

Last month, a total of 1,393 Nissan Leafs were delivered to buyers and lessees, bringing the yearly total to 12,383.

That's significantly lower than the 18,941 delivered in the same eight-month period last year--reflecting the combination of an aging model, anticipation of an imminent longer-range version, and perhaps low gasoline prices as well.

The Leaf remains the highest-volume plug-in car sold in the U.S., with a total of 84,705 delivered since it went on sale in December 2010.

2015 Chevrolet Volt

2015 Chevrolet Volt

As for the Chevy Volt, 1,380 were delivered in August, bringing the year's eight-month total to 8,315.

A total of 81,672 Volts have been delivered since December 2010.

ALSO SEE: 2016 Chevrolet Volt - full review

Both models are likely to make news this month, with details of the 2016 Leaf potentially released in the next 30 days--and the first of the all-new and longer-range Volt plug-in hybrid going on sale before the end of September.

While it will take both of those cars a while to make it to dealers, we expect to see an uptick by December, though plug-in sales are historically lower during the winter.

2015 BMW i3 REx - Driven, Portland OR, April 2015

2015 BMW i3 REx - Driven, Portland OR, April 2015

Meanwhile, August sales of the BMW i3 were 792, roughly where they've been holding this year--for an eight-month total of 6,183.

Almost 12,300 of BMW's innovative electric car--the most energy-efficient vehicle available in the U.S.--have been sold since its launch in May 2014.

PRIOR MONTH: Plug-In Electric Car Sales In July: Leaf Plummets, Volt Holds

Tesla Motors refuses to release standard monthly sales figures by market for its Model S electric luxury sedan, so we can't say how many of that vehicle were sold in August.

Plug-in hybrids: high-volume

As for the plug-in hybrids, the Toyota Prius numbers continue to wane.

2012 Toyota Prius Plug-In Hybrid, Catskill Mountains, NY, Oct 2012

2012 Toyota Prius Plug-In Hybrid, Catskill Mountains, NY, Oct 2012

The Prius Plug-In Hybrid production having ended earlier this year--and a new version not due until the end of 2016.

Just 344 plug-in Priuses were delivered in August, its lowest total since February 2012--the very first month it went on sale.

MORE: 2016 Toyota Prius: Full View Photos Finally Leaked

As for Ford's Energi plug-in hybrids, it sold 723 C-Max models and 949 Fusion versions, both modestly higher than the July figures.

Each of the eight-month totals, however--4,959 and 6,091--is down on the total for the same eight-month period last year, however.

Low-volume entries

Finally, there's the largest number of plug-in cars: those that are low-volume (for various reasons) and the California compliance cars sold solely to hit volume targets imposed by the state for zero-emission vehicles.

2015 BMW i8, test drive in greater Los Angeles area, Apr 2014

2015 BMW i8, test drive in greater Los Angeles area, Apr 2014


Of the low-volume cars, however, in the plug-in hybrid category, the $135,000 BMW i8 sport coupe had the highest monthly sales: 210 units, bringing its year-to-date total to 1,160.

It was followed by one of the pair of Porsche E-Hybrid models, the Cayenne at 83 and the Panamera at 36, for eight-month totals of 646 and 289 respectively.

The Cadillac ELR range-extended electric sport coupe fell between those two, selling a low 45 for a year-to-date total of 704.

That August sales figure was the lowest monthly ELR delivery figure since January 2014, its second month on the market.

2016 Cadillac ELR

2016 Cadillac ELR

Another two Honda Accord Plug-In Hybrids were also delivered, bringing this year's total to 62 for a model that never had much impact and is now defunct.

Battery-electric vehicles

As for the low-volume electric cars and California compliance cars, Volkswagen's e-Golf had a stellar month, with 381 sold (its second-best month ever) for a 2015-to-date total of 2,212.

Its pricier German counterpart, the Mercedes-Benz B-Class Electric Drive, knocked out another 172 deliveries to get to an eight-month total of 1,540.

And its Daimler stablemate, the tiny Smart ForTwo Electric Drive, waned somewhat, to an August total of 106, for 861 so far this year.

The Ford Focus Electric exceeded its average 2015 sales pace, with 176 delivered for an eight-month total of 1,122.

2014 Chevrolet Spark EV - First Drive, Portland, July 2013

2014 Chevrolet Spark EV - First Drive, Portland, July 2013

The Chevrolet Spark EV minicar, with more inventory received from South Korea, rose to 135 for August and a year-to-date total of 2,015--due largely to more than 900 sales in March.

Mitsubishi delivered 6 i-MiEVs for a sad year-to-date total of 90.

And no more Honda Fit EV or Toyota RAV4 EV compliance cars have been delivered for several months now.

Finally, the makers of the Fiat 500e and the Kia Soul EV refuse to report the sales of those models, making it impossible to look at how they're doing.


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