Cost effective storage must be developed for LNG to power market
Arup will advise the world’s largest annual gathering of LNG leaders to recognise the potential of prefabricated storage tanks as a cost effective approach to storage in the small and mid-scale LNG to power market. The Arup energy team, presenting at Gastech 2017, predicts that a move to ‘plug and play’ modular cryogenic storage units could save the industry up to 20% on the construction of mid-scale storage tanks – important at a time when LNG prices are being driven down.
In countries that have an established gas distribution network, the capital costs of receiving, storing and regasification at each power station can inhibit the development of LNG to power projects. The traditional solution for large scale in-situ-constructed LNG storage has typically utilised 9% nickel steel single, double or full-containment, flat bottomed, storage tank systems – with the technology hardly progressing in the past 20 years. These systems can be costly because of the bespoke design required for each tank, and the on-site man hours required for building and assembly.
Arup is urging the industry to consider prefabricated LNG tank solutions, using cryogenic, membrane technologies, as a technically feasible alternative. There is a need to develop ‘plug and play’ tanks based on standard solutions, that are robust enough to be transported anywhere in the world. Modular LNG tanks bring significant savings as they can be designed in advance to suit a range of site conditions; they can be constructed off-site in advance to facilitate ordering off the shelf and transported to site in an as-built form. This will reduce the man hours required for a project and allow significant savings in achieving first gas. In addition, labour intensive activities are transferred from often remote project sites to a dedicated fabrication yard, with greater availability of specialised labour. Tank parts can also be prefabricated under cover, further increasing productivity and the quality of workmanship.
Single containment systems may not be appropriate for all projects. The Arup team is progressing double and full containment designs using precast wall panels and wired wound pre-stressing combined with membrane lining technology that will reduce site area and deliver significant cost savings.
John Powell, Associate Principal, Arup, Houston said: “There are projects being proposed all around the world that are showing membrane, modular solutions are both needed and viable. However, what has surprised us most is that there is no major coordinated push towards prefabricated solutions at mid-scale. We are at Gastech 2017 to advise industry leaders that more cost-effective and programme friendly tank solutions are achievable for the small to mid-scale LNG to power markets. This is an opportunity for us to work together to bring about a significant change for the industry.”