The Energy Systems Laboratory at the Texas A&M Engineering Experiment Station, in partnership with Fort Hood, and Drexel University, plan to demonstrate the design and operation of an efficient thermal microgrid through retrofitting and upgrading existing district energy systems at Fort Hood to improve energy efficiency in Department of Defense (DoD) installations. This project is a Phase I feasibility study to evaluate the solutions with measured site data and energy models. The technical objectives of this Phase I feasibility study are to demonstrate:

1. Facility operational benefits (e.g., energy and water savings, electric demand reduction, campus operational effectiveness, energy and water resilience) derived from the improved thermal microgrid functionality through electrification and optimization of thermal load management using energy models and virtual tested.
2. Thermal microgrid feasibility, robustness, long term cost effectiveness and scalability for Fort Hood and broader DoD deployment.

Three thermal microgrid configurations, including thermal loops that can optimally manage the thermal loads among different district energy plants, centralized air source heat pump systems, and distributed water source heat pump systems, will be explored and evaluated through a model-based approach. The major technical approach will rely on the data analysis, modeling, and model-based optimization. EnergyPlus, as a whole-building simulation program, will be used for detailed building performance evaluation. Modelica, which is known to model dynamic thermal networks, will be used to model the thermal loop interactions among district energy plants. Artificial intelligence-based models will be trained, based on detailed physics-based models, to provide cost-effective control models. By working closely with the Fort Hood team, the project team will further refine candidates in the district energy plants and buildings for the project. Then, the project team will use a holistic approach to conduct a performance and economic analysis to facilitate evaluations of three thermal microgrid configurations in terms of energy and water savings and energy resilience. More specifically, below are the following tasks:

1. Collect district energy system and buildings data to establish baselines.
2. Design thermal microgrid system configuration.
3. Develop a simulation-based virtual testbed and validate models using the collected data.
4. Explore intelligent operations of thermal microgrid through predictive controls.
5. Conduct thermal microgrid system performance evaluation and economic analysis.

A 30% heating, ventilation, and air conditioning system energy and cost reduction achieved through the application of the thermal microgrids would offer more than $300M per year savings potential across all existing DoD facilities with district cooling systems. Further savings will be enabled through the application of this technology for new sites and renovations. Achievable annual energy savings amount to 1.5 billion kWh per year, which would derive a tangible reduction of 575,620 metric tons of CO₂ per year. Extending the system to other DoD district heating systems has the potential to save an additional 0.0315 quadrillion British thermal unit per year. Furthermore, it is anticipated that energy and water resilience will be significantly improved through thermal microgrids. (Anticipated Project Completion - 2026)