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For example, an average adult doing light work produces about 510 British thermal units (Btu) per hour. Half of this is "sensible heat" which raises the temperature of the room. The rest is "latent heat" in the form of moisture which must be removed from the air by the air conditioner.
"Appliances produce heat in proportion to the rate they consume energy," Walter said.
Electrical appliances produce 3.4 Btu per hour per watt of power they draw.
"Just a few large appliances can add a large amount of heat to your home," Walter said.
Both a coffee maker and vacuum cleaner, for example, produce 2,500 Btu per hour. A large color television produces about 1,500 Btu per hour.
Lighting also adds a significant amount of heat gain.
"A 2,000-square-foot office building can require two tons of air conditioning (24,000 Btu per hour) just to remove the heat produced by the lights," Walter said.
Some activities and appliances put moisture in the air, and it must be removed by the air conditioner.
"Cooking a meal and washing dishes adds about one pint of moisture to the air," Walter said. "A shower produces about 1/2 pint of moisture."
Internal heat gain accounts for about 15 percent of total air conditioning energy use in a typical residence. It can be as much as 50 percent in a small office building.
"There are no rules of thumb that let you predict which houses have-high radon concentrations," said Bruce Snead, extension specialist in residential energy at Kansas State University.
It was initially thought that new homes have higher radon levels because they are built more tightly and have fewer air changes to dilute the radon.
"In the same way, if a new home is built more carefully, it will have fewer entry paths for radon gas," he said.
Older homes may be more vulnerable to the gas because they have suffered more foundation movement. This movement opens up joints and other potential entry points.
"Elevated radon levels have been found in all types and ages of houses," Snead said. "The only way to measure the level inside a particular house is to test for radon."
There is a variety of lighting timers. The more expensive timers designed for lighting actually adjust for the change in daylight hours during the year. However, the more common timers must be manually reset.
"The most common criticism for photo cells is they allow the lights to come on earlier than necessary and turn off later than necessary," said Gene Meyer, extension mechanical engineer at Kansas State University
"In theory, a timer can be more precisely set to turn off and on, thus saving lighting costs," Meyer said. If the lights are being used for security, photo cells or more expensive lighting timers are good alternatives.
"However, if your lighting is being used for advertising, a combination of a timer and a photo cell may be a better alternative."
"The photo sensor should be wired in series with a timer," Meyer said.
The timer should be set to turn on in the late afternoon and turn off later at night when the sign is not needed. Since the photo eye is in series with the timer, the photo eye prevents the light from coming on until dark. The timer turns the light off at the specified time. This minimizes operation time of the light.
"Be sure to use a good quality timer with a battery back-up or spring mechanism to prevent having to reset the timer after every power outage," he said.
"The Kansas Corporation Commission (KCC) provides a toll-free telephone number for consumers with utility-related inquiries or problems," said John Wine, KCC chairman.
You are asked to first contact your utility and try to resolve the issue. If you are not satisfied, call the KCC at 1-800-662-0027.
The Consumer Protection Section of the Office of Public Affairs at KCC will answer calls between 8 A.M. and 5 P.M., Monday through Friday.
The receptionist will take your name and number. Then a member of the Consumer Protection Section will call you to obtain specific information about your question.
"Numerous sources indicate 78 degrees as a reasonable setting for comfort and economic operation," said Bruce Snead, extension specialist in residential energy at Kansas State University.
Setting the thermostat lower increases annual cooling costs by three to four percent for each degree.
"A good suggestion is to start the cooling season with the thermostat at a higher temperature and get used to that comfort level," Snead said.
"Also, remember to turn the thermostat up five degrees or more when you leave the home for more than two hours," he said.
A clock or automatic thermostat can be a very effective way to maintain comfort and reduce cooling costs.
"Yes. Turning the pilot light off during the summer will save energy," said Doug Walter, president of Kansas Building Science Institute. "And if you air-condition your house, you'll save more on your electric bill than you will on your gas bill."
A typical residential gas pilot light consumes about 750,000 cubic feet of gas per month. This heat energy is simply wasted when the furnace is not operating during the summer months. If the house is air conditioned during the summer, however, the pilot light contributes heat to the house that must be removed by the air conditioner.
In dollars and cents, keeping the pilot burning during the summer months costs about $3.00 per month for the gas and about $4.80 per month for the 60 kilowatt-hours your air conditioner will consume getting rid of the heat.
The pilot also creates a draft in the chimney which causes increased air infiltration through windows and around doors, further increasing the air conditioning load.
"Some people have heard that turning out the pilot light in the summer will decrease the life of the furnace," Walter said. "Recent tests have indicated that the possibility for damaging your furnace is minimal or nonexistent.
To extinguish your pilot light, simply follow the printed instructions on your furnace. If the directions are unclear or missing, consult a service technician or your gas utility," he said.
"A certain amount of maintenance is required for air conditioning equipment to operate satisfactorily," said Richard B. Hayter, director of Kansas Energy Extension Service at Kansas State University.
"If air flow across the cooling coil is restricted, the unit's capacity will be reduced," Hayter said.
Be sure to inspect and replace or clean, if necessary, the filters in your furnace at least quarterly. Secondly, carefully clear any debris that may have collected on the condenser, which is normally located outside your home. Restricted air flow through the condenser can severely limit the unit's capacity.
"You may wish to have the condenser professionally cleaned if it has not received a maintenance check in the past few years," Hayter said. "You may also wish to have a professional inspect the air conditioner's refrigerant charge."
An air conditioner low on refrigerant may result in frost forming on the cooling coils within the furnace, again reducing the flow of air through the coil.
"You won't save any energy, but you can reduce heating time by using preheated water," said Doug Walter, president of Kansas Building Science Institute.
If you have a gas water heater and electric range, you can save on energy costs by using pre-heated water from your water heater. The savings, however, is almost insignificant -- about two-tenths of a penny for every six cups of water heated to boiling.
"The main benefit of using partially pre-heated water is to save time, especially if you're heating a lot of water," Walter said.
"Ideally, whatever measures you take to control sunlight should be adjustable," said Bruce Snead, extension specialist in residential energy at Kansas State University.
This admits sunlight during cold spring periods but shuts it out during a warm fall season.
"Natural shading by trees and vines works best if the plants are tall enough and placed correctly," Snead said.
Solid roofs and overhangs are the best permanent protection against overheating. Overhangs can be designed for the desired shading.
Exterior shades create flexibility, but are hard to mount and vulnerable to weather," Snead said.
Bamboo screens, wood or aluminum slats and woven shade cloth are common materials, usually operated in roll-down systems. While shade paint can be used on glass systems, it is advisable to check with the manufacturer of plastic glazing systems for compatibility with shade paint.
"Interior shades are less effective than exterior shades in blocking solar gain," Snead said.
Cutting nighttime heat loss is possible if there are tight edge seals on insulating materials.
"You can also help cool the space by using natural or mechanical ventilation with your shading system," Snead said.
"Another factor is careful placement of low inlets and high outlets coupled with good prevailing winds," he said. Installation of a fan can also force ventilation to adapt to varying conditions.
"A light colored shingle will be the best choice," said Gene Meyer, extension specialist in small business energy at Kansas State University. "This will help to minimize your cooling costs, especially if your roof is not shaded.
"Dark shingles will increase the cooling load but will not significantly reduce your heating requirements," Meyer said.