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The first dedicated FPSO application offshore was by Arco in the Ardjuna

field in the Java Sea offshore Indonesia in 1976 (D’Souza et al. 1994).

Interestingly, this was a concrete barge with steel tanks, used to store refrigerated

liquefied petroleum gas (LPG) moored to a buoy using a rigid arm system in 42.7m

water depth. The first tanker-based single-point moored FPSO facility for oil is

said to be the Castellon for Shell offshore Spain in 1976. This facility was meant to

produce oil from a subsea completed well, some 65 km offshore Tarragona. It

began operations in 1977, and was designed for a 10-year field life.

Compared to these early days, floating production systems have now

evolved to a mature technology that potentially opens up the development of

offshore oil and gas resources that would be otherwise impossible or uneconomical

to tap. The technology now enables production far beyond the water-depth

constraints of fixed-type offshore platforms and provides a flexible solution for
developing short-lived fields with marginal reserves and fields in remote locations

where installation of a fixed facility would be difficult.
Generally ship shaped floaters with provisions for storing and offloading of

oil simultaneously. They may be designed to weathervane so that they always face
the weather, minimising roll and heave motions. In benign environments such as

West Africa and South East Asia, the FPSO may be spread moored to face one

direction at all times.

Some FPSOs for Brazil have been designed to semi-weathervane by using a

spread mooring with slack aft moorings, giving the vessel the options of some

limited weat hervaning

Oil production is through either flexible risers or riser towers with flexible

jumpers. The motions of the FPSOs generally prohibit the attachment of rigid

vertical risers or steel catenary risers.

The FPSOs have a large area for setting a deck on the top of the hull.

However, many FPSO hulls are conversions and the deck structure may not be

designed to carry a Floating Offshore Platfornz Design processing facility. This
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