Although companies like Waymo have demonstrated a taxi service utilizing fully self-driving cars, the head of German automotive supplier ZF doesn't predict such technology to become a market reality before 2030.

"I'm a little bit more skeptical than some announcements that we've heard," ZF CEO Wolf-Henning Scheider told Automotive News (subscription required) in an interview published Tuesday. "From our point of view, it will take several more years."

Although Waymo is building up its fleet of self-driving cars, the company's taxi service isn't yet fully open to the public and the cars themselves still require a human driver at all times to take over in case of an emergency, or in poor weather it seems.

ZF is among the companies in the race to develop a reliable and robust self-driving system, and Scheider said the technology will be rolled out slowly as it advances. He said ZF would introduce its first self-driving service in 2021. It will be a shuttle service running along a closed circuit at Brussels Airport.

However, ZF doesn't only see a self-driving taxi service as an opportunity. The company also plans to offer parts such as steering, powertrain and computer systems to companies manufacturing self-driving cars.