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Our Technology - An Overview

Direct Exchange utilizes a transfer of heat energy from stable subsoil temperature to an environmentally safe and friendly refrigerant, which travels to a heat pump inside your home or business through copper loops. The result is MAXIMUM comfort for you, your family, your employees and everyone who enters your home or business.

Direct Exchange heat pumps can be installed in almost every situation imagineable. Since there is no need for visible outdoor equipment, the system can be installed on almost any size lot under most areas (such as lawns, driveways, landscaped areas).

The system can be installed in new construction or as part of an upgrade to an existing structure. It can use your existing ductwork. There's no reason not to upgrade!

Efficiency

Our Direct Exchange heat pump provides 300-600% more energy than it requires for operation. This incredible efficiency ratio results in a typical reduction of energy bills by 40-70%. With this high efficiency ratio, Direct Exchange geothermal is more cost-effective to operate than other heating and cooling systems. The possible net return to the consumer is 3-6 times the cost of operation.

Safety & Environmental Benefits

Since the Direct Exchange heat pump does not burn fossil fuels (unlike conventional furnaces), the potential fire hazard from an open flame is completely eliminated. This also has the added benefit of reducing emissions containing carbon dioxide, nitric oxide, and sulfur dioxide. This reduction in greenhouse gas emissions has a direct impact on our environment.

For instance, the installation of a Direct Exchange system for a typical home has roughly the same effect on the environment as planting an acre of trees. Currently throughout the United States, the number of Direct Exchange systems installed also saves roughly 14 million barrels of crude oil per year.

The refrigerant used in the Direct Exchange system is NU-22B (ASHRAE number R-422B). NU-22B is the drop-in replacement for R22 (the current refrigerant used in most applications which is being phased out of use). NU-22B is NOT harmful to the environment as it has an ozone depletion potential of zero. It's completely non-toxic, non-flammable, and has an A1 classification. As an added benefit, NU-22B requires lower operating pressures which can dramatically increase compressor life.

More information about NU-22B can be found through the ICOR International website. ICOR International is the manufacturer of NU-22B for Free Source Energies.

System Benefits

A few key benefits of the Direct Exchange system:

• Operates as a heating AND cooling system
• Typically has a smaller footprint than existing/previously installed equipment
• Underground components carry an exceptional warranty
• Reduce overall energy consumption and save on monthly energy bills
• Extremely quiet (producing about as much noise as a newer refrigerator)
• No outdoor unit to conceal
• No open flame or flammable fuel required for operation
• Incredible Energy Efficiency (300-600%)
• Energy savings generally pay for the system in a few years
• Utility companies and government offices often have rebate programs available for installation

How Direct Exchange Geothermal Works

In Direct Exchange systems, refrigerant is circulated through highly conductive copper tubing inserted in the ground. These are generally 50-foot or 100-foot loops buried in the ground (usually in a three-inch hole drilled into the ground) and surrounded by a conductive grout. Each earth loop is connected at a central location (manifold) and main lines provide the connection to and from the heat pump in the building. In the winter, the refrigerant collects heat from the earth and carries it into the building where it is released. During the summer, the system is reversed, thus collecting heat from the building and releasing it into the earth. Additional heat generated or not expelled by the system is also used to supplement the water heating requirements of the building in which it's installed. This is especially the case in the summer months, when heat is being removed from the building.

The reason this system works and can be efficient is that the temperature in the soil several feet below the surface remains more or less constant throughout the year. If you've ever been in a cave, you will have personally experienced this fact of nature.

Direct Exchange vs. Water Source Systems

Geothermal heating and cooling systems are comprised of two basic types: Water source and Direct Exchange.

Water source systems are most commonly installed as a closed-loop system (although open-loop systems are available for some installations) where a water/antifreeze mixture is circulated via a water pump through the system. Heat is transferred to the water from the ground in the external loop in the first step. Heat is then transferred from the water to a refrigerant within the heat exchanger. The heat exchanger's compressor circulates the refrigerant to an air heat exchanger (typically in an air handler unit), where it is finally distributed to the living space. Note that there are typically three exchanges of heat in a water source system. Each time heat is transferred, some heat energy is lost. This system requires three heat transfer steps and also electricity to operate water pumps.

Direct Exchange systems obtain useful geothermal energy by transferring heat to/from the ground through a copper-walled tubing to a safe refrigerant circulated by a compressor. The compressor circulates the refrigerant to an air heat exchanger, where it is distributed to the living space. Direct Exchange systems only have two heat transfer steps, resulting in less heat energy loss.

All heat pumps (Direct Exchange, Water Source, or Air Source) operate under the basic process of phase changing. Phase change occurs when a refrigerant fluid (for example) is converted between its liquid and gas states. When a phase change takes place, large amounts of heat energy are consumed or rejected.

As an example, when 1 pound of water is heated 1 degree (F), 1 BTU of heat energy is consumed. When water reaches 212 degrees (F), before it phase changes from liquid to gas, about 970 BTUs of energy must be consumed (per pound). This also applies to refrigerants.

Water Source systems do not phase change in the ground. Therefore, only 1 BTU of heat energy can be transferred per pound of water per 1 degree (F) temperature change.

Direct Exchange systems do phase change in the ground. As a result, while in heating mode, about 970 BTUs of heat energy can be transferred per pound of refrigerant.