Clean Heating Solutions for Oil and Gas Wells in Low-Temperature Environments: Operational Performance and Techno-Economic Assessment of Multi-Configuration Air-Source Heat Pump Systems

Against the backdrop of an accelerating global low-carbon energy transition, oil and gas field enterprises as traditional energy producers are under immense pressure to reduce energy consumption and carbon emission intensity in their production operations. During hydrocarbon extraction, particularly in gathering, transportation, and treatment processes, continuous thermal energy input is essential to maintain fluid mobility, prevent freezing, and meet process requirements. The resultant energy consumption constitutes a significant component of both operational costs and carbon footprints. Consequently, effectively reducing energy consumption in gathering/processing systems while achieving clean heating alternatives has emerged as one of the key imperatives for oilfield enterprises pursuing green. Western China's desert regions harbor abundant oil and gas resources, yet their extreme environmental conditions impose severe challenges on production equipment. Taking this oilfield as a representative case, its location deep within a typical desert basin subjects operations to ground temperature extremes ranging from −33.2°C to 70.6°C. Under such conditions, extracted fluids require continuous heating at well sites to ensure safe and uninterrupted transportation. Historically, gas-fired heaters and electromagnetic heaters have served as primary heating solutions, but the former suffers from fossil fuel consumption and direct carbon emissions, while the latter incurs prohibitively high electricity demands. To support China's dual-carbon goals and advance clean energy adoption at well sites, heat pump technology has emerged as a promising alternative due to its utilization of ambient thermal energy, high efficiency, and low carbon footprint.[1] Consequently, the oilfield has deployed nearly 100 heat pump units across multiple configurations, including single-stage, cascade, transcritical CO2, and solar collector-integrated systems, aiming to replace conventional heating methods. However, the actual operational performance and reliability of air-source heat pumps under frigid conditions remain inadequately validated.[2] The absence of systematic field data and in-depth analysis has created significant uncertainty, severely constraining large-scale implementation of this technology in similar harsh-environment oilfields. To address this research gap and scientifically evaluate the applicability and energy efficiency of various heat pump systems under extreme cold conditions in actual well sites, this study implemented systematic field monitoring and analysis of seven representative heat pump systems configurations during a typical low-temperature season. The investigated systems encompassed single-stage, cascade, transcritical CO2, and flat-plate collector-integrated units. Throughout the winter operational period (November 2024 to March 2025), the research team collected 3000 high-resolution datasets capturing critical parameters including flow rates, inlet/outlet temperatures, partial composition and ambient conditions. Applying the first law of thermodynamics and standardized heat transfer models, we quantitatively evaluated three key performance indicators: actual heat delivery capacity, coefficient of performance (COP), Clean replacement rate. Through comprehensive techno-economic analysis considering capital expenditure and operational outcomes, this research identifies optimized solutions for clean thermal energy supply in hydrocarbon fields under analogous extreme environments.