The promises of microalgae-still a long way to go.

Over the past decades, interest in microalgae has grown exponentially. Especially industrial applications, such as biodiesel production from microalgae were hyped in the early 2000s. But since the first attempts to commercialise microalgae-derived products for energy applications, only a few developments made it to the market. What is hindering the full exploitation of this valuable resource for food, feed, and energy applications? This opinion paper reflects on the state of the art of industrial microalgae culturing and the knowledge gaps which still need to be filled jointly by academia and industry.