Hybrid sales were up by 10 percent in September, compared to a year ago. But the total year-to-date numbers tell a more accurate picture. So far in 2010, automakers have sold 10 percent fewer gas-electric hybrids, in an overall auto market that has grown by about 10 percent.

2010 Volkswagen Jetta TDI Cup

Volkswagen Jetta TDI Cup Edition

The September hybrid sales figures once again prove that sales of fuel-efficient cars, especially hybrids, rise and fall with gas prices. The price of gasoline is modestly up from a year ago—by about $0.25—but consumers usually respond to rapid increases, rather than the nominal price.

While sales of hybrids and small cars are down, vehicles with clean diesel engines showed continued strength. All but one clean diesel model made decisive gains compared to last September, boosting overall clean diesel sales by 124.1 percent compared to a year ago. Volkswagen sold nearly 5,000 Jetta TDI units in September. The availability of the Jetta TDI as a fuel-efficient wagon is unique in the marketplace. This upward trend for diesel could continue, but only to a modest degree, because very few new clean diesel models are on the horizon.

Meanwhile, the number of hybrids on sale in the United States is expected to expand from 27 today to approximately 55 by 2015. If compelling new models are offered, and gas prices rise, the hybrid market could significantly climb. If gas prices remain flat, then it doesn’t bode well for hybrids or the new breed of plug-in cars hitting the market later this year.

The Honda CR-Z, introduced last month, reported its first full month of sales. Between 1,236 units of the CR-Z sporty hybrid coupe, the 1,679 sales of the Insight, and a few Civic Hybrid sales, Honda jumped over Ford to become the second biggest seller of hybrids. Sales of Fusion Hybrid dipped by nearly 45 percent compared to last month. Ford sold its very first units of the Lincoln MKZ hybrid, but we’ll need a full month of sales to establish a benchmark.

The Toyota Prius continues to dominate hybrid sales, even though sales are essentially flat since last month, year-over-year, and year-to-date. This could be considered an accomplishment for Prius, considering the overall downward trend in hybrid sales, and the poor performance of both Toyota Highland Hybrid and Toyota Camry Hybrid, which are both down by about 40 percent for the year.

These figures underscore the desirability of unique hybrid nameplates—like Prius, Insight and CR-Z—and point to a trend in which automakers offer green alternative technology vehicles with a specific brand or badge. Toyota is expected to offer an entire family of Priuses, starting with a crossover version of the Prius next year.

September 2010 Hybrid Car Sales Numbers

Hybrids sold in the US (September 2010): 22,193
Hybrid Take-Rate: 2.31%

US hybrid sales for September 2010

Model Units vs. last month vs. September 2009 CYTD vs. CYTD 2009
Toyota Prius 11,394 -3.4% 3.7% 103,334 -1.4%
Honda Insight 1,679 -17.3% -3.8% 15,824 0.2%
Ford Fusion 1,671 -44.5% 49.7% 16,275 41.9%
Honda CR-Z 1,236 78.1 n/a 1,930 n/a
Lexus RX450h 1,112 -18.8% -4.8% 10,883 7.9%
Toyota Camry 1,104 -5.2% 26.6% 11,179 -39.5%
Ford Escape 793 8.9% 0.8% 8,776 -26.9%
Lexus HS 250h 711 19.7% -42.8% 7,962 346.1%
Honda Civic 667 -12.4% 338.8% 5,156 -63.6%
Toyota Highlander 523 7.6% 94.4% 5,029 -41.8%
Altima 511 79.9% 48.1% 5,221 -32.3%
Chevy Silverado 201 -38.7% 154.4% 1,361 96.7%
Mercury Milan 85 -9.6% -41.0% 786 -30.7%
Chevy Tahoe 85 3.4% -69.6% 1,166 -50.4%
Mercedes S400 83 -1.2% 76.6% 760 1001.4%
Cadillac Escalade 82 -6,8% -56.6% 908 -44.6%
Mazda Tribute 53 -3.6% 89.3% 494 -43.5%
Mercury Mariner 49 -21.0% -46.2% 701 -50.1%
GMC Yukon 48 -36.8% -67.1% 948 -25.6%
GMC Sierra 31 -39.2% -24.4% 386 27.0%
Mercedes ML450 24 -69.6% n/a 763 n/a
Lexus GS450h 18 20.0% -52.6% 228 -32.7%
BMW ActivHybrid 7 9 -65.4% n/a 62 n/a
Lincoln MKZ Hybrid 10 n/a n/a 10 n/a
Lexus LS600hL 9 -40.0% -25.0% 90 -56.5%
Chevy Malibu 2 -83.3% -98.7% 387 -89.6%
BMW X6 2 -33.3% n/a 233 n/a
Saturn Aura 1 -66.7% -96.7% 46 -85.1%
All hybrids 22,193 -7.5% 10.7% 200,947 -9.3%
All vehicles 958,966 -3.9% 28.5% 8,620,557 10.3%

September 2010 Clean Diesel Car Sales Numbers

Clean Diesels sold in the US (September 2010): 8,075
Diesel Take-Rate: 0.84%

US clean diesel sales for September 2010

Model Units vs. last month vs. September 2009 CYTD vs. CYTD 2009
Volkswagen Jetta 4,841 14.0% 96.7% 32,338 12.6%
BMW X5 695 24.1% 878.9% 5,604 144.2%
Volkswagen Golf 435 -7.8% n/a 4,116 n/a
Mercedes GL320 413 7.8% 227.8% 2,470 34.0%
Audi Q7 328 -11.6% 16.7% 2,246 73.0%
Mercedes ML320 363 35.4% 26.9% 1,839 -25.4%
BMW 335d 307 -10.0% 802.9% 2,748 202.6%
Audi A3 307 -9.2% n/a 2,385 n/a
Jeep Cherokee 218 70.3% 94.6% 963 20.7%
VW Touareg 118 -2.5% 38.8% 1,265 146.1%
Mercedes R320 49 63.3% 157.9% 265 -11.7%
Mercedes E320 1 -98.4% -99.2% 111 -90.1%
All clean diesels 8,075 10.3% 124.1% 56,350 40.0%
All vehicles 958,966 -3.9% 28.5% 8,620,557 10.3%