Using The Cool Ground To Cool Your Home

If you dig down five feet in the middle of a desert, the ground will be cool. You can use this inherent coolness to keep the temperature down in your home as well.

One of the things you notice when you visit a cave is the cool temperature. The outside air can be hot enough to boil an egg on the sidewalk, but once you step down into the cave, you encounter cool and dehumidified air. This is because the temperature below ground level tends to remain at a constant level. This temperature can be calculated roughly by knowing the average temperature of the above ground air. For example, the city of Chicago has an average temperature in the area of 72 degrees. This average comes from the fact that it drops to 10 degrees in the winter, and swelters at over 100 degrees in the summer. The 72 degree day is a rare, if welcome, break in the extremes.

It is the average, however, and the layers of earth tend to insulate very well. It is reasonable to assume that after centuries of this average temperature, any air trapped underground would settle out at this average temperature and maintain it. This has led to the idea that this constant temperature air underground could be tapped for both heating and passive air conditioning. If your home happened to be built on top of a large cave, you could run a pipe from your home to the cave. Using fans to cause circulation, the cool air could be pulled up from the cave, and the ambient air from the home could be pushed down into the cave.

Since many homes do not happen to be located on top of caves, the idea has been conceived of digging artificial caves under homes and laying pipes to connect them to the homes. A system like this would require only the power it takes to run the fans that would facilitate the proper circulation between the “cave” and the home. It would eliminate the use of compressors which draw the majority of power used in air conditioning.

Another version of this plan would involve the laying of long pipes underground. The idea here is that the “cave” is not necessary. Simply running the air underground through the pipes would allow the air to be cooled. An underground pipe system would be a bit expensive and awkward to install in an existing building. It would be a little less difficult in new construction as the pipes could be laid during the excavation that would take place in laying the foundation of the building.

Regardless of any initial expense, a passive underground system would need little or no maintenance, and beyond circulating fans, little or no energy consumption. Although passive pipe air conditioning, like solar powered air conditioning, is new and mostly experimental today, the combination of global warming and increased population is making an energy solution to air conditioning critical.

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Can You Use The Sun To Cool Your Home?

When you think about the sun, heat is usually the first impression one gets. A recent twist on the idea has led to the possibility of cooling your home with the sun. Seriously!

Environmental concerns are a very important factor in a number of areas and air conditioning is one of them. The wide spread use of air conditioning has created ever increasing electrical energy demands, and the power generating capacity is struggling to keep up with this demand. During demand peaks created by hot spells, there have been power outages and brown-outs in the past. One of the ideas that has been developed to cope with this problem is the use of the sun as a power source. This seems a logical concept since the sun creates the problem by creating heat. How great it would be if the sun could also provide the solution.

In Europe, the technology for using solar energy for both heating and cooling is quite advanced and many larger building have been using a form of it for years. The method used is based on the thermo-chemical process known as sorption. Sorption takes two forms. When a liquid or gas is attached to a porous, solid material it is called adsorption. When the liquid or gas is taken in by liquid or a solid, it is called absorption. The European technology involves the use of a sorbant, usually silica gel. The silica gel is heated by the sun and is dehumidified. When water vapor or steam is added to the dehumidified gel, adsorption takes place and heat is released.

Basically, when heated ambient air is drawn through the system in what is called a heat reclamation rotor, the heat is drawn out of the air, cooling it. The cooled air is recycled back into the building. The major drawback to this system is the large size of the units, and of the area that must be exposed to the sun. This makes its use practical in large buildings, but not applicable for home use.

Solar energy for home use is an emerging technology also. However, the idea here is to use the energy to power existing air conditioning units rather than replacing them with new technology. Photovoltaic cells mounted on the roof converts solar energy into AC power that can be used to power the air conditioner. In most cases, the amount of power is not sufficient to run the unit, but can supplement the regular electrical supply. The major advantage here is that when the electrical demand is the highest, which would be during the peak daylight hours, the sun will be bearing down most directly on the PV cells.

There is a surge in power consumption during start up of an air conditioner unit. Solar photovoltaic cells can be used to keep the unit running at a very low speed during times it would normally be shut down. This can further reduce the regular electrical use by eliminating many of the starts and stops of the cycle. Solar energy is an emerging technology in a world that is seeking alternative sources of power. Hopefully, in the future, the sun, which creates the heat and humidity that we seek to eliminate with air conditioning, will provide the solution to our continued comfort.

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Making Your Air Conditioner Last Longer

Air conditioners are not cheap. You definitely do not want to be buying a new one every year or so. A bit of preventive work can make them last.

One of the biggest problems with most air conditioning units made today is that they are tough, and well built. This may not seem like much of a problem, but what happens is that most home owners become very complacent about their air conditioners. They continue to run and run year after year, and many people tend to worry little about them as long as the air is cool and comfortable. The truth is that without routine maintenance, a normal air conditioning unit loses about 5% of its efficiency each year. This means that within a short time your powerful SEER 13 unit is working more like an older SEER 8.

A good air conditioner can last 15 years, or even longer, with just routine maintenance. It will also operate at its rated capacity for most of that period. Much of the maintenance that is required to keep your unit up to snuff is inexpensive and easy to perform. The first step is to make routine inspections of your unit to discover any potential problems. The best time to perform any air conditioner maintenance is a little bit before it is needed. Check all hoses for leaks and make sure the condensate tube is draining freely.

Filters are critical to the proper and economical operation of the air conditioning unit. They should be inspected often and changed or cleaned monthly. This is even more important during the summer months when there is a higher level of dust and pollutants in the air, and, of course, the units are running more frequently. Other methods of insuring maximum air flow through the system include cleaning and vacuuming of the registers and air vents. You should also insure that furniture and drapes are not blocking registers.

The outside compressor should be cleaned with a hose. Plantings should be kept at least a foot away, and grass and weeds should be trimmed to insure adequate air flow around the unit. Remove any debris from the fan area. During the winter months, the compressor should be covered. It is also a good idea to remove any window air conditioners during the winter, and store them until they are again needed. A yearly tune up of your air conditioner by a certified technician can cost between $50 and $100, but can result in as much as a 5% reduction in yearly operating cost.

You can also increase the life of your air conditioner by finding ways to not have to use it. Programmable thermostats can regulate temperature to decrease use at night or when the house is vacant. Simple things like ceiling fans or attic ventilation fans can reduce the demand on the air conditioner. Even planting trees to increase shade or using drapes over windows facing the sun can help. Reduction of use combined with proper maintenance can increase the life span of any air conditioner. One important safety consideration is to make sure that all power is turned off to the air conditioner before performing any maintenance.

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Efficient Air Conditioners Save You Money

Cool air feels good, but high utility bills do not. Efficient air conditioners can save you serious money over the life of the system and keep you just as cool.

When you are considering the efficiency of an air conditioner, size is everything. Oversized and undersized can be equally bad. When a unit is oversized, it will cycle over and over. The constant starting and stopping of the unit will pull more energy, and the dehumidifying properties of the cooling coils will not have time to fully operate. This will result in moisture being blown into the duct works and the ambient air with each start up. If the unit is undersized it will not be able to generate enough cooled air to maintain the desired temperature, and will run constantly.

Air conditioners are rated on their efficiency using a measurement known as the Seasonal Energy Efficiency Ratio (SEER). This measurement is the cooling output divided by the energy consumption with climate and certain other variables factored in. The higher the SEER number, the more efficient the unit, is the general rule. Older units might have a SEER as low as 7 or 8. For a long time, The Department of Energy mandated a SEER of 10 as the minimum for all newly installed units. This figure has recently been raised to 13, and is a topic for debate currently. Some units are capable of SEER ratings as high as 17 or 18.

Window units use EER (Energy Efficient Ratio) rather than SEER, but the principle is basically the same. The principle of “bigger is not necessarily better” applies to window units also. Humidity plays such an important role in comfort, and is often more important than just mere temperature. Smaller units tend to remove more moisture because they have longer runs. When a unit first starts it actually blows a bit of moisture out of the unit. Once the cycle is running smoothly, the condensation of moisture on the cooling cools begins. Therefore, a longer running cycle is going to provide a more comfortable environment.

There are other factors that will increase the efficiency of an air conditioner and result in a reduction of operating expense. A programmable thermostat is one such idea. The thermostat can be set to automatically raise the ambient temperature at night during sleep or when the home is vacant during working hours. A ten degree raise in temperature setting during these time periods can result in a ten percent reduction in operating costs.

Properly maintaining your system will also result in increased efficiency. Routine changing of filters is one of the most important maintenance requirements. Efficiency of air conditioning is an issue that goes beyond savings to the owner of the home or building. It is an issue of national concern. The wide spread use of air conditioning has created a large strain on electrical power demand especially during heat waves. Power generation is struggling to keep up with demand and brown-outs have become frequent during periods of high demand. Air conditioning efficiency takes place on an individual level, but the air conditioning industry is working to improve efficiency with improved models and the development of new technology as well.

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Multiple Location Air Conditioner

If you are considering an upgrade to your air conditioning, you are going to have to choose a system. Here we cover a unit that is actually separated into two locations.

A dual or separated air conditioner is one where the two main components of the unit are split between two physical locations. Although the initial installation cost is generally higher for a split type air conditioner, they tend to be more energy efficient in the long run. This savings is energy will quickly recoup the installation cost. There is a big noise reduction as the compressor is located in the outside unit. These air conditioners are suggested for use in places where there is a space problem.

The air handling unit is on the inside. This consists of the evaporator section and the duct work that circulates and delivers the air. The fan motor is also located inside along with the filters. The evaporator coil is located inside also. The evaporator coil is where the refrigerant actually vaporizes and the heat adsorption takes place. The thermostat which controls the system is located indoors also, of course, but usually at a more central location where a temperature measurement can be more effectively made.

The divided unit is often referred to as having a cold side and a hot side. The cold side is the indoor unit where cooling actually takes place. The hot side is the outdoor unit where heat is given up from the refrigerant. The hot side unit has a fan assembly to aid in the removal of heat from the condenser coils. It also has its own control logic.

Split air conditioners are used in homes as well as business buildings. Many office buildings and retail establishments use split types due to the larger size of the condenser units. The larger size condensers can be located more easily outdoors behind the buildings, or in some cases, on the roofs of the buildings. Very large buildings and most multi-story buildings have problems using split systems due to the distance between the units. Duct work becomes unmanageable at such distance and results in too much inefficiency. Water chiller units are generally more appropriate for these types of structures.

Another type of split system is known as the mini split system air conditioner. Since an estimated 30% of energy consumption results from duct work loss of cooling, the mini split system eliminates duct work. It operates more like a window unit except that it is connected to an outside condenser by means of a conduit. The conduit requires only a 3 inch hole in the wall to connect the units. The conduit contains the power cable, refrigerant tubing, suction tubing, and a condensate drain. These systems are popular because of their small size and flexibility. They can be floor units, some of which are mounted on casters and can be moved to where they are most needed. They can also be mounted on the walls or ceilings. As many as four individual units can also be connected to a single outdoor unit.

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