About Geothermal

We utilize our extensive training & experience to design and install systems that provide our customers with unmatched economy, reliability & comfort.  

There are many ways to design a geothermal heating and cooling system; open loop, earth loop and pond loop and we are glad to honestly explain the advantages and options available to you.

Geothermal is great for the environment. On October 3, 2008 Congress passed the Energy Improvement and Extension Act which offers a one-time tax credit of 30 percent of the total investment for residential ground loop or ground water geothermal heat pump installations, with a maximum credit of $2,000 for a single residence. The legislation also provides a credit of 10 percent of the total investment, with no maximum credit, for commercial system installations.

To qualify for the tax credit, residential systems must meet Energy star requirements and legislation is retroactive to residential systems installed after Dec. 31 2008.  Owners can file for the credit by completing the Renewable Energy credits subsection on their 2008 tax return forms. No proof of purchase is required, however, in case of an audit, owners must have a detailed invoice of their purchase on file.

Geothermal systems tap the free, completely renewable, supply of solar energy stored just a few feet below the Earth's surface and use that energy to drive heating and cooling systems. In addition to utility, state and now federal tax incentives that enhance the affordability of geothermal systems, this cost-effective, environmentally friendly technology offers a host of benefits that includes:

  • Free, renewable supply of solar energy
  • Efficiency ratings up to five times higher than those of ordinary heating and cooling systems
  • Savings on utility bills up to 70 percent
  • Reduced carbon footprint since the system burns no fossil fuels.
  • More even distribution of heating and cooling for improved comfort
  • Improved indoor air quality
  • Quiet operation with no noisy outdoor units
  • Safe operation that requires no open flame or fuel storage tanks
  • Less maintenance
  • Increased system longevity (average life span 24 years versus 12 to 15 for conventional air conditioners)

Geothermal Heating and Cooling - An Introduction

Geothermal heating and cooling is in step with the times--- and with the future. “Green” technologies---which work with the environment instead of against it---continue to gain momentum amid concerns over pollution and energy conservation.

Geothermal technology is proven, reliable and safe. It significantly reduces energy usage and utility bills for homeowners and business owners. Hundreds of thousands of geothermal systems are saving money and protecting the environment across North America, Europe, Asia and Australia. 

   

Geothermal Basics

How does a geothermal heating and cooling system work? 

Outdoor temperatures fluctuate with the changing seasons but underground temperatures don’t.  Four to six feet below the earth’s surface, temperatures remain relatively constant year-round. A geothermal system, which typically consists of an indoor unit and a buried earth loop, capitalizes on these constant temperatures to provide “free” energy. In winter, fluid circulating through the system’s earth loop absorbs heat and carries it indoors. The indoor unit compresses the heat to a higher temperature and distributes it throughout the building. In the summer, the system reverses, pulling heat from the building, carrying it through the earth loop and depositing it in the cooler earth. 

What makes a geothermal system different from ordinary systems?

Unlike ordinary systems, geothermal systems do not burn fossil fuel to generate heat; they simply transfer heat to and from the earth to provide a more efficient, affordable and environmentally friendly method of heating and cooling. Typically, electric power is used only to the unit’s fan, compressor and pump. 

What are the components of a geothermal system?

The three main parts consist of the heat-pump unit, the liquid heat-exchanger medium (open or closed loop), and the air-delivery system (ductwork).

How efficient is a geothermal system?

All heating and cooling systems have a rated efficiency from a U.S. governmental agency. Fossil fuel furnaces have a percentage efficiency rating. Natural gas, propane, and fuel oil furnaces have efficiency ratings based on laboratory conditions. To get an accurate installed efficiency rating, factors such as flue gas heat losses and cycling losses caused by over sizing, blower fan electrical usage, etc. must be included. 

Geothermal heat pumps, as well as all other types of heat pumps, have efficiencies rated according to their coefficient of performance or COP. It’s a scientific way of determining how much energy the system produces versus how much it uses. Most geothermal heat pump systems have COP’s of 3-4.5. That means for every one unit of energy used to power the system, 3-5 units are supplied as heat. Where a fossil fuel furnace may be 78-95 percent efficient, a geothermal heat pump is about 300 to 500 percent efficient. Some geothermal heat pump manufacturers and electric utilities use computers to accurately determine the operating efficiency of a system for your home or building. 

Do geothermal systems require much maintenance?

No. Geothermal systems are practically maintenance free. When installed properly the buried loop will last for generations. And the other half of the operation—the unit’s fan, compressor and pump—is housed indoors, protected from the harsh weather conditions. Usually, annual checks and filter changes are the only required maintenance.  

What dose geothermal mean for the environment?

Geothermal systems work with nature, not against it. They emit no greenhouse gases, which have been linked to global warming, acid rain and other environmental hazards.  The system includes an earth-loop antifreeze, which will not harm the environment in the unlikely event of a leak. Much of the Climate Master product line uses R-410A, a performance-enhancing refrigerant that will not harm the earth’s ozone layer. 

Geothermal Heat Pumps

Are all geothermal heat pumps alike?

No. There are different kinds of geothermal heat pumps designed for specific applications. Many geothermal heat pumps, for example, are intended for use only with higher temperature ground water encountered in open-loop systems. Others will operate at entering water temperatures as low as 25ÍF, which is possible in closed-loop systems. Most geothermal heat pumps provide summer air conditioner, but a few brands are designed only for wither heating. Geothermal heat pumps also differ in the way they are designed. Self-contained units combine the blower, compressor, heat exchanger and coil in a single cabinet. Split systems allow the coil to be added to a force-air furnace or air handler and utilize the existing blower. 

How does a geothermal heat pump work?

Anyone with a refrigerator or an air conditioner has witnessed the operation of a heat pump, even though the term heat pump may be unfamiliar. All of these machines, rather than making heat, take existing heat and move it from a lower temperature location to a higher temperature location. Refrigerators and air conditioners are heat pumps that remove heat from colder interior spaces to warmer exterior spaces for cooling purposes. Heat pumps also move heat from a low-temperature source to a high-temperature space for heating.

An air-source heat pump, for example, extract heat from outdoor air and pumps it indoors. A geothermal heat pump works the same way, except that its heat source is the warmth of the earth. The process of elevating low-temperature heat to over 100 degrees F and transferring it indoors involves a cycle of evaporation, compression, condensation, and expansion. A refrigerant is used as the heat-transfer medium, which circulates within the heat pump. The cycle starts as the cold, liquid refrigerant passes through a heat exchanger (evaporator) and absorbs heat from the low-temperature source (fluid from the ground loop). The refrigerant evaporates into a gas as heat is absorbed.

The gaseous refrigerant then passes through a compressor when the refrigerant is pressurized, raising its temperature to more than 180 degrees F. The hot gas then circulates through a refrigerant-to-air heat exchanger where heat is removed and pumped into the building at about 100 degrees F. When it loses the heat, the refrigerant changes back to a liquid. The liquid is cooled as it passes through an expansion valve and begins the process again. To work as an air conditioner, the system‘s flow is reversed.

Does a geothermal system heat and cool?

One thing that makes a geothermal heat pump so versatile is its ability to be a heating and cooling system in one. With a simple flick of a switch on your indoor thermostat, you can change from one mode to another. In the cooling mode, a geothermal heat pump takes heat from indoors and transfers it to the cooler earth through either groundwater or an underground earth loop system. In the heating mode, the process is reversed. 

Will the minimum entering water temperature affect which geothermal heat pump I buy?

Yes. If you have an open loop system, your entering water temperatures (EWTs) may range from the 70s in the southern United States to the 40s in Canada.  All heat pumps can handle temperatures in the moderate-to-warm range. A closed loop system, on the other hand, may encounter EWTs below freezing. Not all-geothermal heat pumps will operated efficiently at those temperatures. It’s important to know what EWTs at which your heat pump will operate most efficiently. 

Can a geothermal system also heat water?

Yes. Some geothermal heat pumps can provide all your hot water needs on demand at the same high efficiencies as the heating/cooling cycles. An option called a desuperheater can be added to most heat pumps. It will provide significant savings by heating water before it enters your hot water tank. 

In The Loop

Do I need separate earth loops for heating and cooling?

No. The same loop works for both. To switch heating to cooling, or vice versa, the flow of heat is simply reversed.

Does the underground pipe system really work?

The buried pipe, or earth loop, was an important technical advancement in heat pump technology. The idea of burying pipes in the ground to gather heat energy originated in the 1940’s. New heat pump designs and more durable pipe materials have been combined to make geothermal heat pumps the most efficient heating and cooling systems available today. 

What types of loops are available?

There are two main types: open and closed. 

What is an open loop system?

An open loop system uses groundwater from an ordinary well as a heat source. The groundwater is pumped into the heat pump unit where heat is extracted and the water is disposed of in an environmentally safe manner. Because groundwater is a relatively constant temperature year-round, wells are an excellent heat source. 

How much groundwater does an open loop system require?

The water requirement of a specific model is usually expressed in gallons per minute (g.p.m.) and is listed in the unit’s specifications. Generally, the average system will use 1.5 g.p.m. per ton of capacity while operating, but the amount of water required depends on the size of the unit and the manufacturer’s specifications. Your contractor should be able to provide this information. Your well and pump combination should be large enough to supply the water needed by the heat pump in addition to your domestic water requirements. You probably will need to enlarge your pressure tank or modify your plumbing to supply adequate water to the heat pump. 

What do I do with the discharge water?

There are a number of ways to dispose of water after it has passed through the heat pump. The open discharge method is the easiest and least expensive. Open discharge simply involves releasing the water into a stream, river, lake, pond, ditch or drainage tile. Obviously, one of these alternatives must be readily available and have the capacity to accept the amount of water used by the heat pump before open discharge is feasible. 

A second means of water discharge is the return well. A return well is a second well bore that returns the water to the ground aquifer. A return well must have enough capacity to dispose of the water passed theough the heat pump.  

Are there any laws that apply to open loop installations?

All or part of the installation may be subject to local ordinance, codes, covenants or licensing requirement. Check with local authorities to determine if any restrictions apply in your area. 

Does an open loop system cause environmental damage?

No. They are pollution free. The heat pump merely removes or adds heat to the water. No pollutants are added. The only change in the water returned to the environment is a slight increase or decrease in temperature. 

Can I reclaim heat from my septic system disposal field?

No. An earth loop will reach temperature below freezing during extreme conditions and may freeze your septic system. Such usage is banned in many areas. 

What problems can be caused by poor water quality?

Poor water quality can cause serious problems in open loop systems. Your water should be tested for hardness, acidity, and iron content before a heat pump is installed. Your contractor or equipment manufacturer can tell you what level of water is acceptable. Mineral deposits can build up inside the heat pump’s heat exchanger. Sometimes a periodic cleaning with a mild acid solution is all that’s needed to remove the build-up 

Impurities, particularly iron, can eventually clog a return well. If your water has high iron content, make sure that the discharged water is not aerated before it’s injected into a return well. 

What is a closed loop system?

A closed loop system uses a continuous loop of buried polyethylene pipe. The pipe is connected to the indoor heat pump to form a sealed, underground loop though, which an environmentally friendly antifreeze-and-water solution is circulated. A closed loop system constantly re-circulates its heat-transferring solution in pressurized pipe, unlike an open loop system that consumes water from a well. Most closed loops are trenched horizontally in areas adjacent to the building. However, where adequate land is not available, loops are vertically bored. Any area near a home or business with appropriate soil conditions and adequate square footage will work. 

What if I don’t have room for a horizontal loop?

Closed loop systems also can be vertical. Holes are bored up to 250 feet per ton of heat pump capacity, depending on where you line. U-shaped loops of pipe are inserted in the holes. The holes are then backfilled with a sealing solution. 

How long will the loop pipe last?

Closed loop systems should be installed using only high-density polyethylene pipe. Properly install, these pipes will last for many decades. They are inert to chemicals normally found in soil and have good heat conducting properties. PVC pipe should never be used. 

How deep and long will my trenches be?

Trenches are normally four to five feet deep and up to 600 feet long, depending on the number of pipes in a trench. One advantage of a horizontal loop system is being able to lay the trenches according to the shap of the land. As a rule of thumb, 500-600 feet of pipe is required per ton of system capacity. A well-insulated 2,000 square foot home would need about a three-ton system with 1,500-1,800 feet of pipe. 

How are the pipe sections of the loop joined? 

Pipe sections are joined by thermal fusion. Thermal fusion involves heating the pipe connections and then fusing them together to form a joint that’s stronger that the original pipe. This technique creates a secure connection to protect from leakage and contamination. 

Will an earth loop affect my lawn or landscape?

No. Research has proven that loops have no adverse effect on grass, trees, or shrubs. Most horizontal loop installations use trenches about 24 inches wide. This, of course, will initially leave temporary bare areas, but they can easily be restored with grass seed or sod. Vertical loops require little space and result in minimal lawn damage. 

I have a pond nearby. Can I put a loop in it? 

Yes, if it’s deep enough and large enough. A minimum of six feet in depth at its lowest level during the year is needed for a pond to be considered. The amount of surface area required depends on the heating and cooling load of the structure. You should opt against using water from a spring, pond, lake or river as a source for your heat pump system unless it’s proven to be free of excessive particles and organic matter. They can clog a heat pump system and make it inoperable in a short time. 

Can I install an earth loop myself?

It’s not recommended. Good earth-to-coil contact is very important for successful loop operation. Nonprofessional installation may result in less-than-optimum system performance.