Engineers at Hawaii Oceanic Technology are working on the development of a giant, automated fish farm in the shape of an immense sphere to raise entire schools of tuna just kilometres from the shores of the archipelago state.

The Oceansphere project envisages the construction of a pod of highly automated geodesic spheres measuring nearly 55 metres in diameter for the purpose of housing and raising entire schools of tuna in the depths of the sea.

Hawaii Oceanic Technology (HOTI) said each of the spherical fish farms will be large enough to contain as many as 1,000 tons of ahi tuna, whose growth will be expedited by their location in the waters of a natural sea environment.

The Oceanspheres will be more than just immense spherical fish cages. They will also serve as hi-tech farming facilities equipped with automated feeding systems, dispensing with the need for staff to constantly attend to the deep water offshore structures.

The spheres will also possess finely calibrated thrusters that will enable them to remain stationary without the use of tethers or anchors, as well as a network of sensors for the continuous supply of data concerning water quality, in compliance with requests from of the Environmental Protection Agency.

According to HOTI CEO Bill Spencer, this technology will make the spheres the first ever fish farms to be capable of raising tuna through their whole life cycle, from eggs to harvestable adults.

HOTI plans to submerge the deepwater pens at depths of approximately 400 metres in the waters of the Pacific Ocean, just several kilometres of the coast of Hawaii.

Following many years of planning and development, the company has obtained a final permit from the Army Corps of Engineers for the construction of 12 of the spheres on a 247-acre site, situated around five kilometres off Malae Point on the island of Hawaii.

The next step for HOTI is to finalize the design for the structure of the Oceansphere, and build a working prototype for testing in the sea over a six-month period next year prior to stocking.

Spencer expects the first harvest from the Oceanspheres to arrive toward the end of 2017, given that the fish take around 18 months to reach a harvestable size.

Some local residents remain opposed to the Oceanspheres, however, claiming that the waste pollution they generate will damage the ecosystem of the North Kohala Coast, which is a whale sanctuary and fish replenishment area.

Some 1,700 people have signed a petition in opposition to the farm, while two years ago 400 people wrote letters to Hawaii’s state Board of Land and Natural Resources, opposing the extension of construction deadlines given to HOTI by the board as it awaited approval from the Army Corps.

According to Spencer, however, the project is environmentally sound, and has the potential to benefit the broad ocean ecosystem by dispensing with the need to capture tuna from wild fish stocks.

HOTI is also mindful of the impact of the project on the regional economy, restricting sales of tuna into Hawaii at 600 tons a year in order to avoid competing with local fisherman.

The company has ambitions to use its patented technology to expand internationally, expecting the market for open ocean fish farming equipment to reach $75 billion by the end of the decade, on the back of surging global demand for seafood.