We are working on engineering commercial heater and electrical power sources and have developed an array of water-cooling jets to permit the SunCell® to run long durations. The 24-hour duration run (post of May 21st) was stopped, and the SunCell® was examined and then put back into operation. It was continuously operated for an additional 32 hours and turned off for the weekend. Except for some corrosion of the top flange bolts due to using tap water as the coolant water during the run, the SunCell® remained in mint condition throughout.
Specifically, the SunCell® was submersed in an 850-liter tap water tank that was initially at room temperature. The SunCell® molten gallium internal temperature remained steady at about 500°C which is a typical operating temperature of a steam turbine power plant. The manifold of water jets maintained a stable external cell temperature while avoidance of localized hot spot formation on the walls was solved using a ceramic liner. The run duration was extended by an additional 32 hours on top of the preceding 24-hour duration run. The limiting thermal tolerance of the water tank was avoided by using an external chiller and by exchanging hot water with cold water from another tank. The results of these trials demonstrate the utility of SunCell® towards the goal of a commercial heater of several hundred kilowatts to service the greater than $8T/y thermal market.