Cold water to limit winter German LNG capacity

Three German LNG import terminals are set to have reduced sendout capacity over the winter because sea water would be too cold to be used at floating storage and regasification units (FSRUs), state-owned operator Deutsche Energy Terminal (DET) has said.

The 5.8mn t/yr Wilhelmshaven 1 terminal, and the planned 4mn t/yr Wilhelmshaven 2 and 5.8mn t/yr Stade terminals are all set to have lower regasification rates in the winter (see table).

FSRUs use an "open-loop" system in the summer, where sea water is warm enough to aid in the regasification process. But sea water can be too cold in the winter, meaning that FSRUs rely on a "closed loop" — where steam from the ship's boilers is used to heat water. This can slow regasification.

When the three terminals are regasifying with a closed loop, sendout capacity between all three is set to fall by a total of 207 GWh/d from the open-loop configuration. The 5.8mn t/yr Elbehafen terminal's regasification rate is unaffected in the winter, as it has an external heating source, DET said.

The closed-loop system usually starts when the water temperature drops below 14°C, although it depends on the type of FSRU and other factors, DET told Argus, adding that there is no universal answer to exactly when a FSRU would switch from using a closed to an open loop.

Assuming that FSRUs switch from using an open to a closed loop at a sea temperature of 14°C, the closed-loop system would operate from October to May or June (see temperature graph).

Wilhelmshaven's sea temperature today was 14.2°C, according to data from the US' National Oceanic and Atmospheric Administration. But sendout limited to 172 GWh/d would not affect the terminal if it regasifies at present rates (see Wilhelmshaven graph).

By Martin Senior

Wilhelmshaven sea temperature

Wilhelmshaven sendout

German terminal sendout capacity changes