
Ground Loop DesignTM 2012 Residential Edition is a versatile and easy-to-use program that assists the trained geothermal HVAC designer in designing and selling geothermal residential systems. The program is a turn key tool that first off clearly defines each step in the design process and then enables the designer to quickly and accurately perform each of these steps . In addition, at each step, the program offers a variety of reports that clearly and attractively demonstrate to clients the economic and environmental benefits of the design.
From calculating loads and determining vertical borehole, horizontal trench and pond heat exchanger requirements to modeling C02 emissions reductions and sizing an appropriate circulation pump, GLD 2012 Residential Edition is an invaluable tool for geothermal professionals (note: Residential projects are defined as projects with peak loads of up to 200 kBtu/hr. Larger loads generally are indicative of a commercial system and warrant the additional controls and features found in our commercial product).
In addition, the program has an English/metric conversion engine and is available in many languages, providing applicability to the widest range of equipment and customers.
New in GLD Residential 2012 is the ability to design hybrid geothermal systems, control pipe spacing in the borehole and design horizonal systems using the brand new fixed area mode.
Main Features in the Residential Edition
The studio is the desktop work area in which the designer conducts his or her project analyses and designs. One window may be used to enter loads data, another to design a horizontal or vertical heat exchanger, and still others to provide easily accessible graphs or charts that may be required repeatedly through the course of a design. Similar design plans can be compared directly, or entirely different designs can be created and varied. All of the information a designer needs exists in one convenient location within Ground Loop Design.

To accurately size a geothermal heat exchanger, designers needs to accurately determine both peak and annual, or energy, loads. Most heat loss programs calculate only peak loads, which are adequate for the sizing of regular HVAC equipment. Geothermal loop sizing however requires annual loads as well because the heat rejected to or extracted from the earth changes the soil temperature which in turn impacts the required ground loop lengths.
GLD's loads calculation is designed specifically and exclusively for geothermal applications. Using bin weather data fron dozens of countries, the calculator is simple, flexible, accurate, fast and includes internal/solar gains adjustments. Outputs include peak hourly and cumulative annual loads that are used for loop/heat exchanger sizing. Designers also have the option of importing their peak loads from another program for use by GLD
To accurately size a geothermal heat exchanger, designers first need to accurately determine both peak and annual, or energy, loads. Most heat loss programs calculate only peak loads, which are adequate for the sizing of regular HVAC equipment. Geothermal loop sizing however requires annual loads as well because the heat rejected to or extracted from the earth changes the soil temperature which in turn impacts the required ground loop lengths.
GLD's loads calculator is designed specifically and exclusively for geothermal applications. Incorporating bin weather data from dozens of countries, the calculator is simple, flexible, accurate, easy to use and includes internal/solar gains adjustments. Outputs include peak hourly and cumulative annual loads that are used for loop/heat exchanger sizing. Designers also have the option of importing their peak loads from another program for use by GLD. Please note that the loads calculator at present time is a separate program that integrates smoothly with the loop sizer.


After calculating or importing loads, the energy analyzer determines the amount of energy consumed by the ground source heat pumps each year. Users specify the peak entering fluid temperatures and electricity rates to determine energy usage by the heat pumps as well as any auxiliary systems. Please note that the energy analyzer at present time is a separate program that integrates smoothly with the loop sizer.

The C02 emissions calculator automatically compares annual C02 emissions from the geothermal system with the emissions from four standard HVAC systems. The calculator is location-specific, calculating the emissions based off of the fuel mix used to generate the electricity in the design location. Typically, geothermal HVAC systems reduce overall residential C02 emissions by roughly 30%. The C02 emissions reports are useful for convincing your clients of the thoroughness and benefits of your design. Please note that the emissions calculator at present time is a separate program that integrates smoothly with the loop sizer.
The next step in the design process involves transferring loads data into the zone manager. The zone manager stores loads data and matches heat pumps to the zones.
When considering geothermal applications, the precision of the zone/loads model is crucial because it relates directly to the extent of external heat exchanger installation. Heat exchanger costs impact the overall costs of the project. Additionally, a unit that is called only when necessary or is well matched to a zone will be more efficient than a larger unit that may cycle more often.
Inputs for Ground Loop Design's Zone Manager Loads module include peak hourly load and annual running percentage information for each of the zones in an installation. These loads data can be calculated with the included loads calculator or imported from another loads program. These loads data automatically are matched to heat pumps stored within Ground Loop Design's Heat Pump Database, ensuring rapid and ideal sizing. This loading information can be simple or complex, depending on the level of detail the designer desires. To facilitate this model, each zone has its own panel that shows both the zone's loads and the corresponding equipment.

Now that the pumps have been selected, users proceed to designing the heat exchanger. GLD offers three heat exchanger design modules for vertical, horizontal and pond designs. The modules are intuitive to use and ideal for rapid "what if" modeling. The modules offer a blend of automatic and manual controls. For example, users can manually enter the soil temperatures and automatically select the soil and fluid type parameters.

The simple and discounted cash flow tools enable your clients to understand the immediate and long-term financial benefits of your geothermal design. The tools allows designers to enter project specific info such as tax incentives, interest rates and installation costs (determined based on the previously calculated drilling/piping requirements) and then the program calculates and graphs the payback. In many cases, geothermal designs are cash flow positive from day one and have short payback periods. With this tool, users can effortlessly modify assumptions and recalculate the payback. Please note that the payback calculator at present time is a separate program that integrates smoothly with the loop sizer.

The Pressure Drop Calculator enables the designer to quickly calculate the system pressure drop and then size an appropriate circulation pump. Please note that the payback calculator at present time is a separate program that integrates smoothly with the loop sizer.


Ground Loop Design's reporting features allow the designer to make hard copies of both the data entered and the resulting calculations. These reports are design records, and are valuable when communicating the design to others involved in the projects.
GLD Residential has over 12 different types of reports ranging from heat pump selection reports to energy usage reports.


Metric and English help files are included with Ground Loop Design. These files aid in the correct verification and entry of the various parameters. The three main topics/design aids currently included under the Tables menu in the Design Studio are Fluid Properties, Soil Properties, and Pipe Properties. A convenient Conversions table with metric/English conversions in two different formats is included as well for reference. Help files can be opened and left as open windows on the desktop, and the user can refer to them as necessary during the design process.
Realizing that designers and engineers have their own preferred resources, Ground Loop Design employs the HTML browser model so that the user has ultimate control over the help files. The designer simply creates a basic HTML file containing customized data, pictures, graphs, charts, etc. and then modifies the included top level HTML files to link to their pages. The system requires a very basic knowledge of HTML, but it offers an extremely flexible system for user customization.
A range of Metric and English help files are included with Ground Loop Design. These files aid in the correct verification and entry of the various parameters. Help files can be opened and left as open windows on the desktop, and the user can refer to them as necessary during the design process.

One of the intrinsic features in Ground Loop Design is the English/metric unit conversion capability. The English/metric option can be used not only to compare values, but it also can be used to quickly make use of specific equipment or loads data supplied in only one format.
Because the reports and help files automatically recognize the selected units, users can obtain different reports and data lists depending on the current state of the Design Studio. Presentation and comparison of project information between different engineers and designers is now a straightforward process.
One of the intrinsic features in Ground Loop Design is the English/metric unit conversion capability. The English/metric option can be used not only to compare values, but it also can be used to quickly make use of specific equipment or loads data supplied in only one format. Please note that at the present time only the loop sizing portion of the program has this functionality.

Ground Loop Design offers the user a great deal of freedom in how he or she enters and uses information. Rather than conforming designs to the software, this software package allows some modification and variation in its included features. Some of the most common areas of customization in Ground Loop Design include the entry of loads and the selection of equipment. Although fully automatic modes are available, the user also has the ability to customize or override the automatic features. Please note that at the present time only the loop sizing portion of the program has this functionality.
Ground Loop Design offers the user a great deal of freedom in how he or she enters and uses information. Rather than conforming designs to the software, this software package allows some modification and variation in its included features.
Some of the most common areas of customization in Ground Loop Design include the entry of loads and the selection of equipment. Although fully automatic modes are available, the user also has the ability to customize or override the automatic features. For example, detailed load information may be included for precision designs, while extremely limited data is enough for rough calculations. Additionally, if the data are available, the designing engineer can enter his or her own pump set to take full advantage of the automatic selection procedures. Also, different families of pumps can be used within a single project, and even individual pumps not included in the pre-defined pump sets can be employed as required.
Another area where customization is possible is in the help files, which are based on HTML. With a simple HTML editor the user can include any tables, data, pictures, graphs, charts, or any other useful information that meets the user's needs. User-added files can supplement or replace the help files already provided with Ground Loop Design.
Because the reports and help files automatically recognize the selected units, users can obtain different reports and data lists depending on the current state of the Design Studio. Presentation and comparison of project information between different engineers and designers is now a straightforward process.

Currently, Japanese, Chinese, Korean, Italian, Spanish, Russian, Czech, Lithuanian, French Romanian, Greek and English versions are available. If you would like a version in your language, please contact us. Please note that at the present time only the loop sizing portion of the program has this functionality.