Students work aims to further adoption of district heating networks in US

A potential technology in the fight against climate change in the United States is the adoption of more energy-efficient HVAC systems known as district heating networks, or DHNs. Audrey Blizard, a graduate student in the Department of Mechanical and Aerospace Engineering, is working on reducing energy loss in these DHNs.

What is a DHN?

DHNs generate heat at a centralized location and disperse it through underground pipes to different locations. This is more energy efficient because it means not every building has to have its own HVAC system installed. However, one of the biggest challenges that comes with DHNs is knowing when to send heat to each building and how to redirect it when it’s not being heated. DHNs also use combined heat and power, which means that the wasted heat that comes off of the power system is recycled and used as heating.  This makes them incredibly energy-efficient.

Challenges of DHNs

DHNs are widely used in Europe, but not so much in the United States. The pipes for these systems run underground, which makes their installation difficult and costly. DHNs pay off in the long run, but the initial installment is expensive. Blizard’s work aims to reduce the operation costs, which will further their adoption. 

Possible Solutions

This is where Blizard comes in. Thus far, she has created an automated technique that will simplify the modeling of these DHNs. Given a map of points for all the buildings that need heating, this model can be used to find the best way to connect all the buildings and reduce energy loss. This makes DHNs easier to design and will eventually be used to make them easier to control. She says, “You want to minimize energy loss while still having the people who use the buildings be comfortable in the temperature. So basically, our goal is comfort but reduced energy loss.”

She is also currently collecting data via a small-scale model of a DHN in her lab. This model allows her to run experiments and gather temperature, pressure and flow rate data, which in turn help her better understand the dynamics of the system. This experimental setup, in addition to the automated modeling technique, are helping Blizard better understand DHNs.  Blizard’s mentor, Assistant Professor Stephanie Stockar, says, “Her research approach is highly multidisciplinary and spans across system dynamics, control systems theory and thermal and fluid sciences and has the potential of advancing the state of the art in the model-based optimization and control of large-scale thermo-fluid systems, which characterize the energy distribution and conversion processes in DHNs. Audrey has been making great progress towards her research goals, and we are very excited about her next steps.”

These next steps will help in the United States’ fight against climate change.

Written by Cassie Forsha, CAR writing intern