EED

EED logo.

Program for borehole heat exchanger design. Its easy of use, short learning curve, quick calculation times and inherent databases make EED a useful tool in everyday engineering work for design of ground source heat pump system (GSHP) and borehole thermal storage. In very large and complex tasks EED allows for retrieving the approximate required size and layout before initiating more detailed analyses. Even for very small plants EED values the effort to do a calculation instead of using rules of thumb is worthwhile.

In ground source heat pump system, heat is extracted from the fluid in the ground connection by a geothermal heat pump and distributed to the building. The fluid is then re-warmed as it flows through the ground. In cooling mode, the process is reversed. This is a renewable, environmentally friendly energy source. This sustainable technique can be used for cooling and heating of houses, cooling of telecommunication switchboards, etc.

Algorithms have been derived from modeling and parameter studies with a numerical simulation model (SBM) resulting in analytical solutions of the heat flow with several combinations for the borehole pattern and geometry (g-functions). Those g-functions depend on the spacing between the boreholes at the ground surface and the borehole depth. In case of graded boreholes there is also a dependency on the tilt angle. The g-function values obtained from the numerical simulations have been stored in a data file, which is accessed for rapid retrieval of data by EED.

Calculation of brine temperatures is done for monthly heat/cool loads. The borehole thermal resistance is calculated in the program, using the borehole geometry, grouting material, pipe material and geometry. Screen Shots

Keywords

Earth energy, boreholes, ground heat storage, ground source heat pump system (GSHP)

Validation/Testing

N/A

Expertise Required

High level of computer literacy not required; engineering background helpful for analysis

Users

Over 100 world wide

Audience

Mechanical, energy, and architectural engineers working for architect/engineer firms, consulting firms, universities and research laboratories.

Input

The program has an easy-to-use interface. Databases provide the key ground parameters (thermal conductivity and specific heat) as well as properties of pipe materials and heat carrier fluids. The monthly average heating and cooling loads are the input data. In addition, an extra pulse for peak heat/cool loads over several hours can be considered at the end of each month. The user can choose between different methods of establishing a monthly load profile. The borehole pattern may be chosen at will from a database of more than 300 basic configurations.

Output

User defined charts and text output of the results are provided.

Computer Platform

Standard PC running Windows 95/98/NT or compatible.

Programming Language

Delphi

Strengths

Fast and easy to use.

Weaknesses

N/A

Contact

Company:

Address:

Iliongr´┐Żnden 159
Lund S-224 72
Sweden

Facsimile:

+46 46 136264

E-mail:

info@blocon.se

Website:

http://www.buildingphysics.com

Availability

Software price is about $540. Free support is given via email for one year. Multiple licenses and school licenses available at lower cost. See web site for on-line manuals (PDF) and demo programs.