Oil shale is a type of unconventional energy with abundant reserves. In the in situ mining technology of oil shale, electric heating technology has become a research hotspot due to its multiple advantages, and electric heater is the core of this technology. Despite growing interest in electric heating for in situ oil shale extraction, there remains a lack of comprehensive reviews that focus specifically on the electric heater – its types, performance characteristics, and design optimization strategies. In this paper, the oil shale electric heater is taken as the research object. First, the four mainstream oil shale electric heating technologies – Shell’s in situ conversion process, ExxonMobil’s ElectrofracTM, geothermal fuel cell, and high-voltage power frequency electric heating technology – are analyzed, and their principles, characteristics, and limitations are elaborated in detail. Subsequently, the research status of electric heaters is discussed in depth, covering various types of heaters and their performance, and existing problems are identified. The key role of numerical simulation technology in the optimal design of electric heaters is emphasized. In the future, structural innovation and numerical simulation technology should be leveraged to further optimize the performance of oil shale electric heaters, continuously improving their heat efficiency, thereby promoting their extensive application in industrial fields.
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