Geomax - Geothermal FAQ
Geothermal FAQ- Frequently asked questions regarding geothermal HVAC systems
General
Savings / Costs / Value:
Installation:
Environment
Retrofitting Your Home:
Geothermal FAQ
General:
Geothermal FAQ: How efficient are geothermal systems?
Geothermal systems are one of the most energy efficient residential heating and cooling systems available today, with heating efficiencies 50 to 70% higher than other heating systems and cooling efficiencies 20 to 40% higher than traditional air conditioners. This translates into considerable savings on your utility bills.
The Department of Energy (DOE) and the Environmental Protection Agency (EPA) have both endorsed ground source heat pump systems as among the most energy efficient and environmentally friendly heating, cooling, and water heating systems available. In a January 2000 study, the EPA concluded the following:
- the higher cost of geothermal installation is paid off in just three to five years of energy savings,
- geothermal systems are low in maitenence, operate quietly, are suitable for warm or cold climates, and
- greatly reduce the emission of greenhouse gases and other pollutants.
Geothermal FAQ: Can one system provide both space heating and cooling for my home? And what about heating hot water?
Yes. Geothermal systems can be a combination heating/cooling and hot water heating system. You can change from one mode to another with a simple switch on your indoor thermostat. Using a desuperheater, some geothermal systems can save you up to 50 percent on your water heating bill by preheating the tank water.
Geothermal FAQ: How does a geothermal system heat water for my home?
Using what is called a desuperheater, geo heat pumps use waste heat to heat hot water. During the summer, when the system is in cooling mode, your hot water is produced free as a byproduct of the thermal process. In winter, while in the heating mode, the desuperheater heats a portion of your hot water. Desuperheaters are standard on some units, optional on others. Stand-alone systems that will heat water all year around can be purchased.
Geothermal FAQ: How much space does a geothermal system require?
Most of the geothermal system installation is underground. Inside the house, the heat pump units are about the same size as a traditional heating and cooling unit.
Geothermal FAQ: How long will my geothermal system last?
Geothermal systems are durable and highly reliable. They contain fewer mechanical components, and all components are either buried in the ground or located inside the home, which protects them from outside conditions. The underground pipe carries up to a 50-year warranty.
Geothermal FAQ: How noisy is the geothermal system unit?
Geothermal systems are very quiet, providing a pleasant environment both inside and outside of the home. They have no noisy fan units to disturb outdoor activities like traditional air conditioners.
Geothermal FAQ: How safe is a geothermal system?
Geothermal systems are safe and protected. With no exposed equipment outdoors, children or pets cannot injure themselves or damage exterior units. They also have no open flame, flammable fuel or potentially dangerous fuel storage tanks.
Geothermal FAQ: Are geothermal systems comfortable?
Geothermal systems moves warm air (90-105 F) throughout your home or business via standard ductwork. An even comfort level is created because the warm air is moved in slightly higher volumes and saturates the building with warmth more evenly. This helps even out hot or colds spots and eliminates the cold air blasts common with fossil fuel furnaces.
 Geothermal FAQ: How effective is the underground geothermal loop system?
The buried pipe, or ground loop, is the most recent technical advancement in heat pump technology. Recently, new heat pump designs and improved buried pipe materials have been combined to make geothermal systems the most efficient heating and cooling systems available.
Geothermal FAQ: What is a geothermal heat pump?
A heat pump is a mechanical device used for heating and cooling which operates on the principle that heat can be moved from a warmer temperature to a cooler temperature. A geothermal heat pump uses the earth to provide warmth in the winter and cool us in the summer. A geothermal heat pump operates just like your refrigerator. If you put your hand behind your frig, you’ll feel the heat that has been removed from the food inside the refrigerator. Geothermal heat pumps use the same principle to move heat to and from the home and the ground.
Geothermal FAQ: How does a heat pump work?
The heat pump moves heat from a low temperature source to a high temperature source. The process of elevating low temperature heat to over 100°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 (liquid from the ground loop). The refrigerant evaporates into a gas as heat is absorbed. The gaseous refrigerant then passes through a compressor where the refrigerant is pressurized, raising its temperature to over 160º F. The hot gas then circulates through a refrigerant-to-air heat exchanger where heat is removed and pumped into the home at about 100º 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 air condition, the flow is reversed.
Geothermal FAQ: How is a heat pump sized?
Geomax’s qualified staff will size your heat pump based on an accurate heating and cooling analysis of the home or building. Factors like the type of windows and insulation R. values are taken into account and a BTU per hour heat loss and heat gain will result. The heat pump is then sized for adequate warmth during the coldest winter night and will keep you cool on the hottest summer day.
Geothermal FAQ: Can geotheraml systems be used for commercial, industrial, or apartment requirements?
Yes! Many geothermal systems are being installed using a multitude of units hooked up to an array of buried vertical or horizontal loops. This simplifies zone control and internal load balancing.
Savings / Costs / Value:
Geothermal FAQ: How will I save money with a geothermal system?
Geothermal systems save money, both in operating costs and maintenance costs. Investments can be recouped in as little as three years. There is a positive cash flow, since the energy savings usually exceeds payment on the system.
Geothermal FAQ: How much does a geothermal system cost?
The initial investment for a geothermal system is greater than that of a conventional system. However, considering the operating costs of a geothermal heating, cooling and water heating system, energy savings quickly offset the initial difference in purchase price.
Costs will vary greatly depending on individual building factors such as heat loss/gain, insulation and heat distribution. On average, a geothermal system for a typical home of 2,000 square feet will cost from $14,000 to $18,000. This represents somewhere around double the costs of a conventional heating, cooling and hot water system. When it comes to payback, Geomax owners often see a 5 – 8 year payback of these additional costs.
Geothermal FAQ: What other costs are there besides the geothermal system?
Expect an installation charge for any electrical work, ductwork, water hook-up, and other provisions or adaptations to your home that may be required. The installer can estimate these costs in advance.
Geothermal FAQ: Are there any incentives for installing a geothermal system?
Some utilities offer rebates or incentives to their customers who purchase a geothermal system. To see what your state has to offer visit the energy star Web site.
Geothermal FAQ: How do geothermal heat pumps compare to conventional HVAC systems?
Although heat pumps normally cost more to install than conventional systems, the increased comfort, lower energy and maintenance costs result in customer satisfaction.
Geothermal FAQ: Will this system add value to my home?
Yes. More and more home appraisers and Realtors are educated and acknowledge a geothermal system as a renewable energy source with greater value.
Geothermal FAQ: What is the life of a heat pump?
Experts believe 18-23 years of serviceable life is expected from ground source heat pumps. This is nearly double that of conventional systems.
Geothermal FAQ: How long will the pipe loop last?
A high-density polyethylene pipe is used in a closed loop system and has a 50-year warranty. Independent tests show a useful life span of over 200 years.
Geothermal FAQ: Are geothermal systems guaranteed?
Nearly all geothermal system manufacturers offer a warranty for major components that is equivalent to the warranties for conventional heating and cooling systems. Manufacturers of plastic pipe used for ground loops typically warrant their products for 50 years.
Installation:
Geothermal FAQ: Are geothermal systems difficult to install?
Most units are easy to install, especially when they are replacing another forced-air system. This is known as a retrofit. Geothermal systems can be installed in areas unsuitable for fossil fuel furnaces because there is no combustion and thus no need to vent exhaust fumes. Ductwork must be installed in homes without an existing air distribution system. Geothermal systems can also be integrated with hydronic heat systems. Your dealer or installer can assess the cost of installing ductwork or plumbing.
Geothermal FAQ: Can I install a geothermal system myself?
It's not recommended. Thermal fusion of the pipe, drilling and trenching are procedures best handled by licensed professionals. Nonprofessional installations may result in less than optimum performance, which could cancel out anticipated savings
Geothermal FAQ: How are the pipe sections of the loop joined?
Thermal fusion and stab fittings are the only acceptable method used to connect pipe sections. Thermal fusion connections are either socket or butt fused together to form a joint stronger than the original pipe. Using barbed fittings, clamps and glued joints are unacceptable and will eventually cause the loop to leak and fail.
Geothermal FAQ: What is the fluid in the loops?
There are two types of antifreeze solutions that are used: propylene glycol and methyl alcohol. These heat transferring solutions are mixed with water to form a solution for your specific climate and ground conditions. Geomax’s geothermal heat transfer solution is a mixture of methyl alcohol and water.
Geothermal FAQ: How far apart are trenches and vertical boreholes spaced?
Trenches are spaced four to five feet apart while boreholes are spaced ten to fifteen feet apart.
Geothermal FAQ: How long does it take to install a horizontal loop system?
This depends on soil conditions, length and depth of pipe, and equipment required. A typical installation can be completed in one or two days.
Geothermal FAQ: How long does it take to install a vertical system?
With the vertical installation, time varies with conditions on the site such as type and depth of the overburden, type and hardness of the bedrock, and the presence of aquifers. Typical drilling times are one or two days; total installation can usually be accomplished in two days.
Geothermal FAQ: What are the advantages and disadvantages of the horizontal and vertical installations?
Horizontal installations are simpler, requiring lower-cost equipment. However, they require longer lengths of pipe due to seasonal variations in soil temperature and moisture content. Since a horizontal heat exchanger is laid out in trenches, a larger area is usually required than for a vertical system. Where land is limited, vertical installations or a compact slinkly-like coil horizontal installation can be ideal.
If regional soil conditions include extensive hard rock, a vertical installation may be the only available choice. Vertical installations tend to be more expensive due to the increased cost of drilling versus trenching, but since the heat exchanger is buried deeper than with a horizontal system, vertical systems are usually more efficient and can get by with less total pipe. Your geothermal contractor will be able to help you decide which configuration best meets your specific needs. For a general description of visit here geothermal loop types.
Environment / Climate:
Geothermal FAQ: How do geothermal systems protect the environment?
Geothermal systems conserve natural resources by providing climate control very efficiently, thus also lowering emissions. Since the heat is extracted from the earth, no fossil fuels are burned to generate heat. Geothermal systems also minimize ozone layer destruction by using factory-sealed refrigeration systems, which will seldom or never have to be recharged.
Geothermal FAQ: What are the environmental benefits of geothermal system?
Geothermal systems conserve energy. Because they move heat that already exists rather than burning something to create heat, they reduce the amount of toxic emissions in the atmosphere. They use renewable energy from the sun, and because the system doesn't rely on outside air, it keeps the air inside of buildings cleaner and free from pollens, outdoor pollutants, mold spores, and other allergens.
Geothermal FAQ: In extremely cold climates, are additional heat sources necessary?
All systems require an emergency back up. Heat pumps can provide all the heat necessary even in the coldest weather. An economic analysis by your contractor should dictate what portion of the heat should be provided by the heat pump and what portion by auxiliary means.
Retrofitting Your Home:
Will my existing ductwork function with this system?
Yes, in most cases. Your dealer or installer will be able to determine ductwork requirements and if any minor modifications are needed.
Will an underground loop affect my lawn or landscape?
No. Research has shown that loops have no adverse effects on grass, trees, or shrubs. Most horizontal installations require trenches about six inches wide. Temporary bare areas can be restored with grass seed or sod. Vertical loops require little space and do not damage lawns significantly.
My yard contains many shade trees. Will this affect ground temperature and my ability to use it as an energy source?
Not at all. The system is installed deep enough that it utilizes constant ground temperature.
Can a geothermal system be added to my fossil fuel furnace?
Yes. Called dual systems, they can easily be added to existing furnaces for those wishing to have a dual-fuel heating system. Dual-fuel systems use the geothermal system as the main heating source, and a fossil fuel furnace as a supplement in extremely cold weather should additional heat be needed.
Will I have to add insulation to my home if I install one of these systems?
Geothermal systems will reduce your heating and cooling costs regardless of how well your home is insulated. However, insulating and weatherizing are key factors in reducing your heating and cooling costs, and increasing your comfort from any type of heating and cooling system.
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