The Header-Coil type oil-to-salt heat exchanger system is based on the exceptional operational experience from the thermal oil and molten salt steam systems and ensure a a safe and reliable heat transfer and optimized performance between the hot and cold TES tanks.
Value-adding engineering design
The oil-to-salt heat exchangers are based on a proven technology, with thermal oil inside the tube and molten salt on the shell side. The heat exchangers are manufactured based on traditional boiler principles. They are 100% welded Header-Coil type designed according to ASME and EN standards. This contributes to many operational benefits compared to the TEMA standard u-tube-type heat exchangers and therefore have the potential to reduce LCOE of CSP plants by up to 5-10%.
Higher ΔT and steam temperatures
Due to the full counter flow design of the Header-Coil heat exchanger, an optimized performance across the entire steam cycle can be achieved contributing to a significant cost reduction. During charge and discharge, higher temperatures can be achieved across the steam cycle.
Compared to the TEMA u-tube type heat exchangers, the Header-Coil technology makes it possible to increase the salt temperature of the hot salt tank while simultaneously reducing the salt temperature of the cold tank. By doing so you achieve a high ΔT between the hot and the cold tanks, as the heat exchanger is not limited by the vertical thermal stresses that occurs in the tube sheet. Likewise, it is possible to design the heat exchanger with a lower approach point (below 2˚C) in the thermal energy storage operating mode. The steam cycle optimization can enable a >10% reduction of the required salt volume thereby achieving a significant CAPEX reduction.
- 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 offers a 5-year guarantee against leakages.
- Rapid ramp-up and flexible operation: The heat exchangers are designed to provide the operator with flexibility, when operating the plant at transient loads and during peak hour operations. Due to the flexible design, the system allows seamless switch between the charging and discharging modes.
The general principle of constructability characterizes the design of our heat exchangers to minimize installation work on site and the economies associated with it. The oil-to-salt heat exchangers 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.
Aalborg CSP places great emphasis on monitoring performance track records of the heat exchangers and consequently to optimize their efficiency. Focusing on design excellence, the heat exchangers have undergone several performance upgrades and cost reduction practices since their first installation.
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 heat exchangers without financial obstacles.