Fifth-generation thermal energy network systems are an installation-responsive, growth compatible solution to accelerate current Department of Defense (DoD) rebuilding and modernization priorities. Yet, deployment remains limited across many installations. 

The objective of this project is to provide the DoD with a high-level thermal energy network feasibility analysis for a full-scale building cluster at one of its demonstration sites, followed by a detailed engineering analysis of a subset of the cluster. These analyses utilize an advanced utility master planning software and transient thermo-fluid modeling tools based on the Modelica language, to deliver a versatile tool for assessing the performance of different thermal energy network configurations that can be applied to scaling efforts across DoD sites. 

The technology leverages thermal energy networks to address energy resiliency and security challenges at DoD sites. Unlike traditional district heating and cooling systems that depend heavily on an increasingly fragile electric grid and centralized gas utility infrastructure, thermal energy networks use a low-temperature fluid loop that leverages the relatively consistent ground temperature as a heat sink or source to enhance efficiency of thermal energy delivery to buildings. This project will demonstrate the feasibility of thermal energy networks at an assigned 20+ building DoD site using Jacobs Virtual Infrastructure, a multi-year scenario-based utility master planning software with life-cycle cost analysis and project planning features. A detailed engineering analysis of a 2-5 building subset will be conducted using Jacobs Dynamic Thermal Analysis & Modeling toolkit, a Modelica-based transient thermal flow modeling tool, to carry out a detailed thermo-fluid network analysis and refine control schemes for optimal performance. Success will be measured through energy, cost, and resilience key performance indicators. The technology transfer plan includes comprehensive written and oral reporting, stakeholder engagement, peer-reviewed written work, software tool training, and the distribution of validated open-source thermo-fluid models to facilitate design basis development for further analysis, expansion of the thermal energy network, and transferability of modeling efforts to future DoD sites. 

Thermal energy networks offer significant cost and performance benefits to the DoD compared to conventional district heating and cooling systems or air source heat pumps. By leveraging geothermal heat exchange, thermal energy networks reduce electricity dependence on the fragile power grid in meeting building thermal loads and enhance energy security by siting the power source at the point of consumption. Previous feasibility studies have shown potential for reductions in peak electricity demand, energy imports, and energy use intensity. The thermal energy network closed-loop design minimizes water consumption compared to heating and cooling using traditional cooling towers, further lowering operational costs. High-level feasibility studies and detailed engineering analysis can help accelerate their adoption at approximately 500 DoD adoption sites. (Anticipated Project Completion - 2028)