Back in the 1980s, most diesel-engined cars sold in the US blew black and smelly smoke. Diesels in general had a bad reputation. Today's modern clean diesels are very different, however, and up until fairly recently Americans weren't so willing to give them a try. People also associated diesels with semi-trucks. But with gasoline prices climbing, US car buyers have been warming up to diesels once again.

According to the Diesel Technology Forum, diesel-powered vehicles, currently just 3 % of the US car market today, will grow by 6% to 9% in 2020. Because of this growing popularity, automakers are responding in kind: up to 40 new models, ranging from small cars to full-size SUVs, will hit the US market between now and the end of 2016. Even US-based oil refineries are investing and producing more diesel because of growing global demand. Unlike some battery hybrids, such as the Toyota Prius, diesels are both fuel efficient and provide solid performance specs. In fact, a diesel engine can reduce a driver's fuel consumption by 20% or more when compared to a conventional gasoline engine.

So why aren't Americans, in general, flocking to buy diesels? Price fluctuations. Basically, the price of diesel fuel goes up and down frequently, thus scaring away many buyers. For comparison, diesels account for about half of new cars and it's becoming more popular in emerging economies as well. But the general consensus remains among analysts and automakers alike: US diesel consumption will continue to increase as buyers continue to shop for efficiency.

Check out the most fuel efficient SUV.