Poughkeepsie, NY District Geothermal System

GEOptimize Inc was retained by Labella Associates to complete the detailed design of a geothermal district energy system serving 19 mixed-use buildings in Poughkeepsie, New York. The system is based on an ambient loop connected to 500-ft vertical closed-loop borefields that act as the primary heat source and sink. Using 8760 hourly building load models, GEOptimize applied TRNSYS transient simulation to evaluate peak loads, annual energy balance, and long-term ground temperature response, and to determine the optimal configuration and placement of ground heat exchanger (GHX) fields relative to the connected buildings. The modelling also assessed integration of supplemental heat sources and sinks, control strategies, and system hydraulics to ensure stable, efficient operation over the full lifecycle of the network.

The scope included design of the central ambient loop and building connections, pipe sizing and hydronic equipment selection, pressure-drop calculations and pump sizing for the distribution system and GHX, auxiliary heating and cooling selection, and development of a comprehensive control sequence and long-term monitoring plan. GEOptimize produced detailed AutoCAD drawings showing borefield layouts, header and manifold configurations, ambient loop routing, valve and sensor locations, and provided fluid and piping specifications to the point of connection with the building mechanical systems. A subsequent redesign evaluated higher propylene glycol concentration impacts on heat transfer and hydraulics, updating borefield sizing, pump requirements, and distribution piping.