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Probably more than you think.
"The Institute for Environmental Research at Kansas State University recently conducted a study on the matter with funding by the American Society of Heating, Refrigerating and Air-Conditioning Engineers," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
"The study concluded that the heat produced by personal computers and other office equipment can contribute significantly to the cooling load of a building," Hayter said.
He offered the following examples: A personal computer used in the test, equipped with a Pentium processor and a 17-inch standard monitor, produced 133 watts of heat. A computer with a 486DX33 processor and a 15-inch monitor produced 125 watts. A laser printer produced 248 watts and a photocopier 181 watts.
"The actual heat released was less than the energy consumption listed on the name plate of the equipment," Hayter said, "but it is important that the cooling loads imposed by office equipment be included in the calculations when sizing cooling systems for buildings."
The Kansas Corporation Commission can and has imposed the Cold Weather Rule during winter months to protect households from services being shut off for nonpayment of utility bills.
"The rule is enacted to insure the health and safety of those households experiencing payment problems that could lead to termination of service," said Bruce Snead, extension specialist in residential energy at Kansas State University.
The rule prescribes methods to keep service on, as long as the customer follows the agreement made with the utility company. Each party has protections and responsibilities.
"The inability to pay does not negate the responsibility to pay," Snead said.
The utility companies are willing to listen to the customer’s situation and work out a payment schedule. The rule also states that if the temperature is to fall below 32 degrees Fahrenheit during the following 24-hour period, that household cannot be shut off.
"If you are going to have difficulty making your payment, contact your utility immediately," Snead said.
Demonstrating the willingness to make payment will guarantee that the utility will make every effort to work with you.
"Clothes dryers generally should be vented to the outside," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
Gas and propane clothes dryers must always be vented outside because the dryer exhaust carries away the products of combustion.
Electric clothes dryers also should be vented to the outside because of the significant amount of moisture in the exhaust stream.
Venting this air inside can greatly increase the relative humidity of the air around the clothes dryer, causing the dryer to take longer to dry clothes. Not only does this reduce any energy savings, it increases wear on fabrics.
If several loads of clothes are run successively through the dryer, the relative humidity of the entire house can be raised to potentially damaging levels. This can cause condensation on windows and inside building cavities, resulting in damage to the building's structure over time.
Since cogeneration is the process of using a single fuel to produce both electrical and thermal energy (heat), it is important to understand your facility’s electrical and thermal energy use patterns.
Typically cogeneration is not feasible unless a facility has high electrical and thermal loads.
The economic benefits of cogeneration depend on energy types and use patterns, availability and cost of displaced and cogeneration fuels, and cost of maintenance.
"Determining the economic feasibility of cogeneration applications is complicated," said Dennis Matteson, extension specialist-mechanical engineer at Kansas State University. "Cogeneration systems are expensive, so it would be advisable to acquire the expertise of a professional versed in energy systems."
"The problem arises at the joint where the roof, wall and ceiling come together," said Bruce Snead, extension specialist in residential energy at Kansas State University. "Full depth insulation may cut off continuous ventilation."
It is necessary to maintain one inch to one and one-half inch of air space over the insulation from the soffit area into the attic. Full depth insulation to the outside face of the wall is desirable.
If this insulation is not firmly fixed or protected, it may be moved by winds and air pressure moving through the soffit vents. This may lead to moisture problems on the interior sheet rock finish.
"The best solution to both problems is to use raised-heel roof trusses with sufficient depth over the wall for the necessary insulation," Snead said.
Regardless of the roof construction, the edge of the insulation over the wall should be protected by baffles which are flush with the exterior face. The baffles should turn up and follow along the truss, maintaining a vent space under the sheathing.
"This should prevent wind driven movement of insulation and reduce the possibility of moisture problems at the ceiling perimeter," Snead said.
Temperature variations can be attributed to several factors. Some of the more common problems are solar or internal loads, poor air circulation caused by obstructed return air, and stratification between floors.
"The solar gain can be high in rooms with large windows facing east, south, or west," said Dennis Matteson, extension specialist-mechanical engineer at Kansas State University. "The problem can be exaggerated if the thermostat is located in rooms with large solar or internal loads."
The thermostat measures temperatures in only one location. If the outside temperature is cold but the area with the thermostat is warm due to the solar load, the other rooms may get cool or cold and the furnace will not operate since it monitors only the warmer room.
"In order to keep good air circulation, it is important to have good air distribution and return systems," Matteson said. "If the return path is obstructed, the air circulation to that area will be reduced."
In rooms without return registers, it is important to leave doors open or provide enough clearance under the door for the return air.
Stratification between floors is the process of hot air rising to the upper floor and cold air falling to the lowest floor. In the winter this problem is often made worse if the thermostat is located in the upper floor. If this floor stays warm by a combination of stratification and solar gain, the fan does not operate and the air from the lower floor is not heated or blended with the warmer air.
In many split level houses this problem can be minimized by operating the fan continually during the spring and fall. During the spring and fall the heating requirements are minimal so the furnace operates infrequently. Operating the fan continually will increase the furnace electrical cost slightly, but will result in more uniform air temperatures.
"The combustion efficiency of the unit will remain fairly constant throughout the year," said Gene Meyer, extension mechanical engineer at Kansas State University. However; combustion efficiency is only one of the factors that determine overall efficiency.
Many factors affect the total efficiency of the steam system. For optimum efficiency boilers should be designed to operate between 70 and 100 percent of capacity. When they are operated at low demand such as yours is during the summer months, the efficiency of the system drops considerably.
Efficiency drops because losses from the boiler and from the distribution system remain constant," Meyer said. "The losses, therefore, consume a higher portion of the output of the boiler when it is operating in a low-load condition."
It is often advisable to install a smaller boiler for summer use. This boiler should be designed to handle the load in the kitchen and in the domestic water heating load.
"It may be possible to use this boiler during the beginning of the heating season as well," Meyer said.
A detailed analysis of the system and its efficiency must be carried out to determine if you can justify economically the installation of a small boiler for summer use.
"Crawl space ventilation is required by code in many areas, said Doug Walter, extension specialist in residential energy at Kansas State University. "A growing body of research, however, indicates that it often is not effective in reducing moisture levels in crawl spaces."
The two most important methods to deter moisture accumulation in crawl spaces are adequate drainage away from the foundation and a moisture barrier over the soil in the crawl space, he said.
"You can create drainage away from the foundation walls with a minimum of a 5 percent slope for a distance of 15 feet from the foundation. This is the ideal," Walter said. Dense ground covers like healthy turf grass also help surface run-off to drain away from the foundation.
Even soil that feels dry inside a crawl space, however, can be a significant source of moisture.
"You can keep this moisture in the soil and out of the crawl space by covering the ground with a six-mil plastic vapor barrier," Walter said. "You should overlap seams in the plastic a minimum of six inches and extend the plastic up the foundation walls six to 12 inches. Use soil, sand or rocks to weight the plastic down around the perimeter and over seams."