Abstract: An oil storage apparatus (111) comprising a buoyant hull (102) comprising a single column of circular or polygonal cross-section. The interior of said hull (102) comprises at least one oil-over-water tank (103), and said oil storage apparatus (111) further comprises means for maintaining said tank in pressed full condition.

Abstract: An oil storage apparatus (111) comprising a buoyant hull (102) comprising a single column of circular or polygonal cross-section. The interior of said hull (102) comprises at least one oil-over-water tank (103), and said oil storage apparatus (111) further comprises means for maintaining said tank in pressed full condition.

Abstract: A generally horizontal distensible tube (1) in the sea containing fluid and oriented in the direction of wave travel, the distensibility being chosen so that the propagation velocity of pressure waves inside the tube (bulge waves) is the same as the velocity of propagation of the waves in the sea. Energy is then transferred from the ocean waves to the bulge wave. Energy extraction means (84, 85) at the stern and/or bow convert the bulge power to useful energy. Said energy extraction means may comprise pistons actuating pumps or linear or rotating generators, or one-way valves allowing the bulge wave to pump fluid via hydraulic accumulators through a turbine. The walls of the distensible tube (1) may be comprised partly of elastomer (86) and partly of inelastic flexible polymer coated fabric (87).

Abstract: A generally horizontal distensible tube (1) in the sea containing fluid and oriented in the direction of wave travel, the distensibility being chosen so that the propagation velocity of pressure waves inside the tube (bulge waves) is the same as the velocity of propagation of the waves in the sea. Energy is then transferred from the ocean waves to the bulge wave. Energy extraction means (84, 85) at the stem and/or bow convert the bulge power to useful energy. Said energy extraction means may comprise pistons actuating pumps or linear or rotating generators, or one-way valves allowing the bulge wave to pump fluid via hydraulic accumulators through a turbine. The walls of the distensible tube (1) may be comprised partly of elastomer (86) and partly of inelastic flexible polymer coated fabric (87).