Conducting a Techno-Economic and Environmental Impact Analysis for the Use of Waste Heat from Geothermal Power Plants in District Heating for Western Anatolia

Binary-cycle geothermal plants are inherently limited by thermodynamics, forcing operators to reinject fluids at temperatures that are still valuable for direct heating. This process results in substantial exergetic waste. While prior research has examined efficiency at the level of individual plants, this study introduces a regional-scale framework to convert these facilities into multi-purpose energy hubs. The research focuses on Türkiye’s Western Anatolia Graben, a region with high geothermal activity that, paradoxically, remains dependent on fossil fuels. By combining meteorological records with operational plant data, we evaluated the existing housing stock of 983,277 residences across 14 districts and modeled the heating requirements for a targeted capacity of 468,719 residences that the proposed system can serve. The results indicate that the currently wasted thermal load in 10 specific districts, including key centers such as Sarayköy and Alaşehir, is sufficient to cover peak winter heating demands without fossil fuel backup. Although the infrastructure requires a significant initial investment of $4.51 billion, the project demonstrates long-term viability with a Levelized Cost of Heat (LCOH) of 62.94 USD/MWh and a payback period of 10.43 years. Beyond economic considerations, the system serves as a major decarbonization tool, capable of cutting residential CO2 emissions by 1.7 million tons annually (a 47.7% reduction). These findings suggest that policy incentives should move away from electricity-only models toward integrated reservoir management to maximize resource efficiency.