4. Pioneer Energy Services (NYSE:PES)
Although it grew by more than 120% in the first six months of 2014, few seem to have noticed Pioneer Energy Services. This firm has made it through the worst, taking a hard hit when natural gas prices dropped through the floor. Today, things have turned around, and the company’s rigs are always running at full speed. With little obstacles ahead, Pioneer has ample room for growth and shareholders could seriously benefit as a result.