FSO
The first
generation of FPSO are the so called FSO, (Floating Storage Offloading unit) is, as its name suggests, a
floating storage device with no production facilities, usually for oil. FSO’s are commonly used in oil fields where it is not possible or
efficient to lay a pipe-line to the shore.
FSRU
A Floating Storage and Regasification
Unit (FSRU) is a floating LNG storage vessel with regasification
and offloading facilities on top. LNG carriers moor alongside the FSRU to
offload LNG to the FSRU to be vaporised. It is the floating offshore
equivalent of the onshore LNG receiving terminal. As the unit is located
offshore or inshore, the LNG can be supplied directly to the unit by
conventional LNG carriers.
FRU
The FRU is also a floating LNG
receiving terminal, but instead of storing the received LNG in cryogenic
storage tanks in the vessel, the gas is instantly vaporized at a high rate,
and is subsequently stored in subterranean reservoirs (in so-called
'salt-caverns') as a high-pressure gas at ambient temperature. This concept
enables very high peak send-out rates combined with large storage capacity.
The FRU is very suitable for supplying large quantities of gas into a large
pipeline distribution network, as they exist in Europe.
The large gas-cavern storage volume also enables the unit to function as a
peak-shaving facility.
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