SGS4 Steam generator systems - molten salt

The SGS4 steam generators using molten salt as heat transfer fluid (HTF) have been developed based on the exceptional operational experience with the SGS3 steam systems.


Value-adding engineering design

The optimized SGS4 system is developed as shell-and-tube type with header-and-coil equipment complying with ASME and TEMA standards. The most significant feature of the optimized SGS4 technology is that it allows the shell-and-tube design to have molten salt on the shell side of all components while maintaining the option to use natural circulation for optimal and stable operation. This translates into up to €4 million saving on auxiliary equipment for the steam generation system designed for a 100MWe reference plant as well as lower operation and maintenance costs for two main reasons:

1. No need for circulation pumps

The natural circulation in the evaporator unit eliminates the use of circulation pumps and the initial investment costs associated with it. Furthermore, the electricity consumption and the risk for operational failures are greatly reduced.

2. Reduced amount of venting and drain valves

The elevated layout contributes to automatic venting and achieves easy draining as the molten salt flows by gravity alone. Therefore, there is less need for venting and drain valves, enabling the customers to save on supporting equipment that they would normally have to purchase. The reduced amount of valves also makes operation and maintenance of the plant easier, especially in typical cases, such as molten salt crystallization, when cleaning of multiple valves becomes a costly burden.

Cost-optimal design

The SGS4 configuration allows smaller material thickness owing to an upgrade in the placement of tube bundles and pipes. While the basic component design is the same as the previous editions, decrease in the material thickness reduces the weight of the equipment significantly and lowers CAPEX of the system by 10%.

Award-winning design features inherited from the former edition

  • Leakage-free design: By eliminating operational mistakes and risk for downtime, productivity, electricity earning and the general payback time of the power plant is greatly improved. As a result of excellent performance track records, Aalborg CSP launched a new standard in the concentrated solar power (CSP) industry by announcing a 5-year guarantee against leakages for the new SGS4 steam generation systems. 
  • Rapid ramp-up of 9 °C/min: The SGS4 can allow a fast ramp-up every morning and at transient clouds. The rapid start ensures more than 30 minute extra energy production of a 9-hour daily operational time and increase daily revenue accordingly.
  • Low pressure drop of 1-2 bar: As the SGS4 design is based on traditional boiler technology with tubes of large diameter, it generally has a low pressure drop on the HTF side and can be pushed down to as low as 1 bar.

Constructability & easy installation

The general principle of constructability characterizes the design of our steam generators to minimize installation work on site and the economies associated with it. The SGS4 boiler systems are all developed to perfectly fit into the plant layout. They are prepared for direct mounting on site, and interconnection piping is also pre-fabricated to reduce the time spent on installation.

Secured to be delivered

As a Danish company, Aalborg CSP A/S has the advantage of arranging loan guarantee through a Danish state owned export credit agency. The agency insures banks against the potential financial and political risks – thereby securing the loan and delivery of our SGS4 steam generation systems without financial obstacles.

Did you know...

that Aalborg CSP A/S is supplying the steam generation system in China for the 50MW Shenzen Jinfan molten salt CSP plant which is a flagship project with its exceptionally long 15-hours energy storage capability?
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