Bitcoin (BTC) mining has traditionally been characterized as an energy-intensive digital process associated with significant environmental externalities. More recently, however, it has emerged as a flexible electrical load capable of integrating with applied energy systems to absorb surplus, stranded, and underutilized energy resources, including curtailed renewable generation, flare gas, landfill methane, and industrial waste heat. Despite increasing evidence of such applications, the literature remains fragmented and polarized, lacking a unified framework that positions BTC mining within applied energy systems, resource monetization strategies, and circular economy paradigms. This study presents a systematic literature review based on a structured Scopus search and screening process, synthesizing peer-reviewed research on the techno-economic, environmental, and energy system dimensions of BTC mining. The analysis develops an integrative taxonomy and a conceptual framework that classify emerging mining-enabled configurations according to their role in energy utilization, system flexibility, and resource monetization. Four strategic families are identified-Resource Monetization, Energy Optimization, Sustainable Mining Innovations, and Symbiotic Partnership Strategies-encompassing eight distinct business model archetypes across sectors including power systems, oil and gas, waste management, agriculture, and residential infrastructure. The findings demonstrate that BTC mining can function as a controllable demand-side resource, enabling improved utilization of variable renewable energy, reduction of energy curtailment, and enhanced economic viability of distributed and off-grid energy systems. In specific configurations, it can also contribute to grid-balancing services and facilitate the valorization of waste energy streams. The proposed framework further evaluates the alignment of these business models with circular economy principles and sustainability reporting standards, highlighting differentiated levels of compatibility and associated revenue opportunities. By reframing BTC mining as a context-dependent applied energy infrastructure component, this study provides a structured basis for assessing its role in enhancing applied energy system flexibility and implementation-oriented energy solutions. It also identifies key research priorities, including hybrid energy-mining system optimization, lifecycle environmental assessment, governance mechanisms, and large-scale system impacts.