Underground Liquefied Natural Gas (LNG) Storage
Presently, LNG storage is conventionally limited to large scale above ground cryogenic storage tanks and more recently, in more cost efficient FSRUs predominantly located near remote ports, industrial parks and power generation plants. The large-scale aboveground cryogenic storage tanks are constructed remotely to comply with safety and regulatory considerations in addition to the functional supply requirements of industrial facilities. Large scale underground storage of LNG in underground caverns was researched and prototyped without commercialization due to the high construction and maintenance cost often arising from geological and groundwater freezing challenges. Smaller scale LNG needs is often not met due to cost inefficiency to construct such storage. Piping LNG over long distances is also inefficient, hence limiting the advantage of liquefied transfer within urban areas. With the wider prospect of LNG in transportation, industrial and urban application globally and more specifically for the context of Singapore, the requirement of storing LNG safely and efficiently in more challenging environment presents immense opportunities for exploration. Consequently, with the added potential to recover and monetize cold energy which is conventionally wasted during regasification due to non-synergistic considerations between storage, regasification and distribution process; further motivates the exploration needs.
The research team attempts to explore cryogenic storage systems for large-to-small scale LNG storage located within underground environment critically for two varied application: Large quantities of LNG stored in underground caverns / basements for industrial applications; and smaller quantities of LNG stored with basements located at urbanized areas.
- WP 1 - to develop an underground storage system (tank-based and containment-based or hybrid) and understand how the system works at various conditions;
- WP 2 – to develop Cold Energy Capture (CEC) technologies with aims to integrate them with the LNG underground storage. The CEC solutions will perform as a viable cold sink and provide a means to monetize the captured cold energy to offset the high cost of underground LNG storage; and
- WP 3 – construction of a Pilot Test Facility that incorporates the containment system and Cold Energy Capture (CEC) technology and its relevant application system developed in WP1 and WP2.
- Model to capture the mechanical, thermal, fluid transfer process, with partial lab verification;
- Address the industry needs for small/ medium scale LNG storage solution;
- Provide solution for LNG storage and how power can be generated in a decentralized manner, especially within urban areas;
- Provide Carbon footprint reduction for business benefits.