Evaluating the economic and environmental viability of hybrid solar-geothermal heat pump systems in Jordan using multi-criteria decision analysis

Jordan is currently facing an energy crisis characterized by a heavy dependence on imported fossil fuels, prompting the nation to target a 50% share of renewable energy by 2030. This study introduces a novel approach by simulating hybrid solar-geothermal heat pump systems tailored to various Jordanian locations, assessing both their energy efficiency and economic feasibility. Unlike previous studies that focused solely on geothermal or solar technologies, this research uniquely combines these two renewable sources, offering a comprehensive evaluation across multiple climates. Key findings include the superior performance factors of vertical (4.0) and horizontal geothermal heat pumps (4.2) in Amman, compared to the air-to-water heat pump (3.5). Additionally, Aqaba station demonstrated an exceptional solar contribution, meeting 99.34% of heating demand, while Amman achieved 77.93%. Notably, Maan station provided the highest solar contribution for space heating at 6,902 kWh/year, and Amman airport station led in CO2 emission avoidance at 2,120.29 kg/year. The economic analysis revealed that while vertical heat pump systems were economically unviable with a negative NPV of -4,987.51 JD, horizontal and air-to-water systems showed promising NPVs of 5,734.27 JD and 8,428.46 JD, respectively, with payback periods of 9.44 and 6.5 years. Additionally, this study is the first to employ both the fuzzy Best-Worst Method (BWM) and Analytic Hierarchy Process (AHP) techniques to rank station suitability, identifying Maan station as the most optimal and Ghor El-Safi as the least. The results underscore the potential of hybrid solar-geothermal systems to significantly reduce energy consumption and CO2 emissions, despite initial financial barriers, and highlight the importance of further investment in geothermal technologies to enhance Jordan's energy security and reduce fossil fuel dependency.