General Motors Co. said it remains committed to bringing alternative propulsion vehicles to market and growing consumer acceptance of electric vehicles, even as it doesn’t expect to reach its goal to have half a million electrified vehicles on U.S. roads by next year.

The carmaker, meanwhile, in its 2015 Sustainability Report released Tuesday said it is ahead of its goal to double the number of U.S. vehicles that generate 40 miles per gallon or more highway fuel economy by 2017. GM said it had nine vehicles that met that criteria last year, up from six in 2014, five in 2013 and two in 2011.

Automakers are facing pressure to boost fuel economy — through internal combustion engines and through alternative technologies such as electrified vehicles — to meet regulatory requirements.

GM said it expects to meet U.S. corporate average fuel economy fleet compliance through 2016 based on its product plans. Automakers must meet standards of 35.5 mpg by 2016 and 54.5 mpg by 2025.

The Detroit automaker said it had 196,861 vehicles on U.S. roads powered in some way by electrification last year, up nearly 9 percent from 180,834 in 2014 and 153,034 in 2013. The automaker in its figures includes vehicles dating to the 2010 model year that are either pure electrics, plug-in hybrid electrics, vehicles with a two-mode hybrid technology or have eAssist — a mild hybrid technology that uses a small electric motor and lithium-ion battery to boost fuel economy.

GM has invested more than $2 billion in electrification since 2010. It blames lower fuel prices and the “increased saturation of electric model offerings in the marketplace” as reasons why it doesn’t expect to meet its 2017 electrification goal.

But David Tulauskas, GM’s director of sustainability, said GM’s commitment to electrification is for the long run and isn’t changing despite low gas prices.

“We see lower gasoline prices as a temporary phenomenon, and if history teaches us anything, it’s that energy market fluctuations — both up and down — are unpredictable,” he said in the report. “Moreover, the price of gas is not cheap everywhere, and in markets like Europe and China it’s still quite expensive. So our commitment is unchanged, and we’re focused on designing, engineering and marketing EVs that will resonate with customers.”

GM Chairman and CEO Mary Barra announced the 500,000 target in fall 2012 when she led GM’s global product development operations.

A new Chevrolet Volt plug-in electric hybrid recently went on sale with 40 percent more range than the first-generation Volt. And GM later this year plans to launch the 2017 Cadillac CT6 plug-in hybrid electric luxury vehicle and the new 2017 Chevrolet Bolt EV. The pure electric vehicle is estimated to have more than 200 miles of range, costs about $30,000 after a federal tax rebate and will be built at GM’s Orion Assembly Plant in Orion Township.

It also recently launched the 2016 Chevrolet Malibu Hybrid, a new model with a combined city/highway fuel economy estimate of 46 miles per gallon.

mburden@detroitnews.com

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