The race to develop the most advanced autonomous driving system has gained fierce momentum in the last few years: Alphabet’s Waymo is developing in-house tech like LiDAR, cameras, and radar for its autonomous minivans, Uber unveiled driverless fleets in cities like Pittsburgh and San Francisco, and Tesla’s “second generation,” or “HW2” vehicles are equipped with the advanced hardware to make fully-autonomous driving a reality.

Now, the tools that make autonomous driving possible, like GPS, sensors, LiDAR, and data-processing chips, are moving off the land–and into the sea.

Two companies in Norway have just unveiled plans to develop the world’s first driverless ship.

The Yara Birkeland–dubbed the “Tesla of the Seas” by company executives–is set to sail in 2018, on a mission to deliver fertilizer 37 miles down a fiord. With a price tag of $25 million, the vessel, which is expected to handle everything from navigating around other boats to self-docking, is roughly three times the cost of traditional container ships its size. Also, the cost of on-site repairs for a ship like this are expected to be high.

Still, those funding the project claim the ship will eventually help save the company up to 90% of its costs by allowing it to hire fewer crew members and cut spending on fuel. Also, the company claims that it will reduce emissions by replacing 40,000 truck drives a year in Norway.

The Yara Birkeland, developed by two Norwegian companies–Yara International ASA and Kongsberg Gruppen ASA–is expected to begin taking short trips in 2018, with the aim to eventually sail on longer voyages. Regulations from the International Maritime Organization will impact how soon the fully-autonomous versions can set sail, with the earliest expected to launch in 2020.

Humans will, at first, remain at the helm. “At first, a single container will be used as a manned bridge on board,” Kongsberg’s chief executive Geir Haoy told the Wall Street Journal. “Then the bridge will be moved to shore and become a remote-operation center. The ship will eventually run fully on its own, under supervision from shore, in 2020.”

In addition to the Yara Birkeland, British manufacturer Rolls-Royce Holding PLC is poised to begin launching robotic ships by 2020, as well, which might include tugboats, ferries, and cargo ships. And Haoy told the Wall Street Journal that his company has already seen interest from operators of a range of ships, such as tankers, fish transporting ships, and supply ships.

Experts see demand for this kind of technology as only growing.

“Automation like this is certain to proliferate over time,” Michael Ramsey, Gartner’s autonomous vehicle analyst, told TechRepublic. “Guiding a large vessel on the ocean is certain to have challenges and it lacks the kinds of things that autonomous vehicles use as guides, like lane lines and street signs, but it doesn’t have the level of interaction with other vehicles that are found on roadways, so it seems like it might be akin to mining, where autonomy has been in place since 2008.

“I suspect there will be more and more attempts to automate different aspects of maritime operations,” said Ramsey. “What I don’t know is just how much of a cost relative to the overall cost of operations that the people on board really add.”

Bryant Walker Smith, an expert in legal aspects of autonomous driving, also commented on the cost of the ships. “So much of modern consumerism depends on the ability to move things vast distances at surprisingly low economic cost,” Smith said.

Still, Smith told TechRepublic that there’s “cumulatively, a high environmental cost and mixed social impacts.” As a result, he said, “automated and solar-powered shipping could therefore have profound economic, environmental, and even social implications.”

How different countries address climate change, and how the cost of fuel changes, will be big determinants in how well these ships “catch on,” Smith said.

A final consideration is the difference between regulating waters close to the coasts and the open seas, Smith said. “Countries can effectively mandate much more in their waters–including fuel and crew,” he added.