A tidal-stream turbine with a diameter bigger than the length of a tractor trailer was installed in China for a project involving Simec Atlantis Energy Ltd., China Shipbuilding Industry Company Ltd. and China Three Gorges Corp. The 18-meter (59 feet) turbine was manufactured in Wuhan and put last week in the waters between two islands in the Zhoushan archipelago, south of Shanghai. While turbines that harness the tides to generate electricity have struggled to compete on cost with solar and wind farms, a move by China to industrialize production could significantly reduce the technology’s price tag.The 500-kilowatt turbine is only a pilot project, but could be the first step toward larger-scale production. “If they go into industrial-scale manufacturing of turbines and we can access that, you’re talking about rapid reductions instantly of the cost,” Tim Cornelius, chief executive officer of Simec Atlantis Energy, said in a phone interview. “It bodes very well for us to compete with floating offshore wind.”Developers of tidal stream projects have long promised that the technology could be a renewable power source that’s more reliable than wind and sunshine. However, by the end of last year BloombergNEF estimated only 12 megawatts of the projects were developed worldwide, a fraction of the wind and solar installations put in each year.

While it may not be possible for tidal technology to catch up with wind and solar, it could be a good option in places such as islands that lack space for land-based renewables and where the seabed is too deep for offshore wind turbines.