30 May 2005

THERMAL AND COST BENEFIT ANALYSIS OF A GEOTHERMAL PILOT PROJECT AT NORTHWEST TENNESSEE CORRECTIONAL FACILITY


The Department of Corrections of the State of Tennessee is conducting an experiment at the
Northwest Tennessee Correctional Facility (NWCX) that is intended to demonstrate the total life cycle
savings that can be obtained by using geothermal heat pump systems to provide heating, ventilating, and
air conditioning (HVAC) and domestic hot water (DHW). The University of Tennessee at Martin (UTM)
Center for Energy Management has been participating in this project since 1999. This paper provides a
description of the: 1) role of the Center for Energy Management and its interaction with the Department
of Corrections and the system designer, 2) guilds and the associated inmate populations, 3) geothermal
system, 4) instrumentation and data acquisition systems, 5) analysis methods, and 6) HVAC and DHW
cost benefit data obtained for the 2003-2004 heating and cooling seasons. These intermediate results show
that the traditional HVAC system used 46% more energy than the geothermal system and the resistive
DHW system used 46% more energy than the geothermal system.