Table 2.

Core category of solar-ORC that used for number of documents obtained.

Category	Query	Number of documents
Applications	TITLE-ABS-KEY (“solar ORC” AND (“application” OR “utilization”) AND (“commercial” OR “demonstration” OR “small scale”))	78
Working Fluids	TITLE-ABS-KEY (“solar ORC” AND (“working fluid”) AND (“selection” OR “optimization” OR “performance” OR “properties” OR “zeotropic”))	298
Expander Technology	TITLE-ABS-KEY (“solar ORC” AND (“expander”) AND (“piston” OR “screw” OR “turbine” OR “vane”))	57
Cycle	TITLE-ABS-KEY (“solar ORC” AND (“cycle configuration”) AND (“recuperation” OR “regeneration” OR “trilateral” OR “flash” OR “comparison”))	33
Design	TITLE-ABS-KEY (“solar ORC” AND (“design” OR “architecture” OR “configuration”))	391
Dynamics and control	TITLE-ABS-KEY (“solar ORC” AND (“control” OR “dynamic”))	218