While still only a small fraction of overall passenger vehicle sales in the United States, clean diesel power is becoming an increasingly popular choice among consumers.

Sales in the first half of 2014 jumped by 25 percent over the same period last year — against an overall increase of only four percent — and some experts figure that the current three percent of the market clean diesels represent could double by 2018.

A report compiled by IHS Automotive for the Diesel Technology Forum used data from HybridCars.com to show steady increases in diesel vehicle registrations over the last four years, including 31 months with double-digit increases.

“The consistently positive sales trends for clean diesel are particularly noteworthy since they have occurred over a recessionary economic period when diesel fuel prices have trended upward, and consumers have many more fuel efficient vehicle choices than ever before,” says Allen Schaeffer, executive director of the Diesel Technology Forum. “Today, the clean diesel choices include 27 cars and SUVs, nine vans and 10 pickup trucks. We expect that number to nearly double in the next 18 months, and we expect that more models in more brands will only generate higher sales in the future.”

Schaeffer believes that customers are attracted by diesel vehicles that are around 30 percent more efficient than their gas equivalents.

While Volkswagen is traditionally the go-to for small diesel cars, Chevrolet is now offering its compact Cruze sedan with an ultra-competitive four-cylinder diesel. Fiat Chrysler is putting its smaller V6 diesel into SUVs like the Jeep Grand Cherokee, but also into the Ram 1500, which is the first light-duty diesel pickup in decades. General Motors will go one smaller by offering four-cylinder diesels in its new mid-size pickup twins, the Chevrolet Colorado and GMC Canyon. And Nissan has confirmed that its new Titan full-size pickup will offer a U.S.-sourced diesel V8 from Cummins.

Higher up the price spectrum, Audi, BMW and Mercedes-Benz are rolling out both four- and six-cylinder diesel engines through more models than ever, including “lifestyle” vehicles like the A7, whose fastback design wouldn’t normally be associated with diesel power.

However, not every manufacturer’s plans have come to fruition. Mazda has had a very public and struggle getting its new SKYACTIV-D engine ready for North America, while both Honda and Subaru have quietly shelved similar plans.

AutoBlogGreen via Diesel Technology Forum