Innovation in solar cell technology has slowed as startups struggle to get a foothold in a tough market and solar panel manufacturers delay purchasing the equipment they need to manufacture more efficient cells. But First Solar, one of the world’s largest solar companies, continues to invest in boosting the efficiency of its solar cells.

The company, which is based in Tempe, Arizona, announced this week that it had set a new world record in efficiency for thin-film cadmium telluride solar panels. The equipment it uses to produce the record-setting panels will eventually be installed on all its production lines. It also announced the acquisition of Tetrasun, a startup with high-efficiency silicon technology that First Solar hopes to bring to market next year. First Solar’s stock jumped from $29 to over $40 on Tuesday and is still above $35 a share.