Exhibition & Conference

13-16 September 2021

Singapore EXPO, Singapore

Technical Programme

Raymond Walsh

General Manager, Process Design & LNG Technology

Wärtsilä Finland

16:00 - 16:30

Tuesday, 17 September 2019

T3.2 Every LNG Terminal Deserves a Good Engine

Growth in LNG usage is enabled by the implementation of small- and medium-scale LNG terminals. The feasibility limitations due to the capital and operational expenses of a standalone terminal can be overcome by combining and integrating with a gas engine power plant.

Large scale LNG terminals are big enough to be implemented as standalone, single-use installations. However, the feasibility of this concept for smaller terminals is hampered by the capex of standalone systems for boil off gas (BOG) handling, heating energy for regasification, and electric, safety, and control systems. The expected opex savings from having high quality and low maintenance terminals are not realised because the minimum standalone operation organisation is larger than should be technically required for the small installation.

New terminals rarely have a ready customer take-off, which leads to a chicken-and-egg situation as the terminal cannot be commissioned without customer demand or take-off, and customers do not want to convert or complete their gas systems until there is an operational terminal.

Integrating an internal combustion engine power plant to the LNG terminal can solve all of these problems. As the engines require 4-6 bar gas pressure, BOG is easily utilised in the engines. All gas venting from the total installation can be collected and utilised in the gas engines.

The cooling water of gas engines is a perfect heat source for reagasification, while exhaust gas heat recovery enables large sendout to pipelines.

Combining the electrical, fire, safety, and control systems improves the overall system quality and reduces both capex and opex. The staffing needed for the combined power plant and terminal is slightly over half the total staffing needed for the separated terminal and power plant. The electric supply from the power plant is more reliable than from the grid.

Constructing the integrated terminal and power plant under a single contract achieves significant contracting and overhead savings. A co-ordinated schedule assures the terminal of power and heat supply and gas offtake when needed. The terminal has a core customer ready while the customer base is rapidly expanded after becoming operational.

There are challenges which can be overcome with good planning. The combined terminal must arrange an electrical supply contract and a gas supply contract. This increases the workload of the developer, but as power generation is a typical driver for LNG terminals, terminal developers are familiar with it. In some markets, a company might not be allowed to be involved in both electricity and gas supply. One solution is for separate companies to own the LNG and the power plant parts of the installation. The various interconnections, supplies and services between them can be modelled, measured, and invoiced, so that the entities are commercially independent while both benefit from the combination advantages.

These benefits and opportunities offer a new way ahead for small- and medium-scale LNG terminals, opening and speeding up the penetration of LNG into more widespread and smaller energy markets.