GLHEPRO

GLHEPRO was developed as an aid in the design of vertical borehole-type ground loop heat exchangers used in geothermal heat pump systems. While GLHEPRO may be used for residential system design, it is aimed at commercial systems. The heat exchanger may be composed of any number of boreholes arranged in various configurations.

GLHEPRO performs three different tasks: (1) Simulation (for up to 100 years) of ground loop heat exchangers to determine monthly average and peak heat pump entering and exiting fluid temperatures, as well as power consumption of the heat pump. (2) Determination of the required borehole depth to meet user-specified minimum and maximum heat pump entering fluid temperatures. (3) Sizing of hybrid ground source heat pump (HGSHP) systems by determination of the required borehole depth and necessary supplemental heat rejecter (cooling tower, fluid cooler) or heat extractor (boiler) size. Screen Shots

Keywords

ground heat exchanger design, ground source heat pump system, geothermal heat pump system

Validation/Testing

GLHEPRO has been validated experimentally and against more-detailed models.  See: Cullin, J.R. 2008. Improvements in design procedures for ground source and hybrid ground source heat pump systems. M.S. Thesis, School of Mechanical and Aerospace Engineering, Oklahoma State University.

Expertise Required

Basic understanding of building simulation (to obtain the requisite loads), HVAC systems, and ground source heat pump systems is assumed.

Users

About 400

Audience

Consulting engineers

Input

Monthly heating and cooling loads on heat pumps; monthly peak heating and cooling loads on heat pumps; heat pump data; ground thermal properties; borehole configuration; maximum and minimum acceptable heat pump entering fluid temperatures (EFT).

Output

Required size of ground heat exchanger corresponding to maximum and minimum acceptable heat pump EFT; required size of supplemental heat source/sink for HGSHP systems; month-end daily average EFT, monthly minimum and maximum heat pump EFT. Also provides input for simulation of ground heat exchangers in EnergyPlus.

Computer Platform

PCs running Windows NT, 2000, XP, Vista

Programming Language

VBA and Fortran

Strengths

Design of vertical, closed-loop ground heat exchangers.

Weaknesses

Does not design horizontal or open-loop ground heat exchangers. Also, requires a separate building simulation program to determine monthly loads and monthly peak loads.

Contact

Company:

Oklahoma State University

Address:

School of Mechanical and Aerospace
218 Engineering North
Stillwater, OK 74078
United States

Telephone:

405-744-5900

E-mail:

glhepro@okstate.edu

Website:

http://www.hvac.okstate.edu/glhepro/

Availability

Cost is $525-$725 for single licenses.