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Yes.
"A number of skylight manufacturers produce units with low emissivity glazing," said Bruce Snead, extension specialist in residential energy at Kansas State University. "It may be offered either as a standard feature or as an option."
One benefit of low-emissivity glazing in a residential skylight is its significant reduction in heat loss in the winter.
"The other advantages are a reduction of heat gain in the summer and less potential for condensation on the inside of the skylight," Snead said.
The low-emissivity coatings are available only on glass products, no acrylic glazing. The additional cost for the option of low-emissivity glass may be 15 to 20 percent over a basic acrylic double-glazed skylight.
"Be sure to ask whether the skylight you are considering is
available with this glazing," Snead said.
"The decision to replace incandescent lights in a church must be based on how many hours these lights are used," said Gene Meyer, extension mechanical engineer at Kansas State University.
Incandescent light are the least efficient of all light sources. If the hours of usage are low, however, it will not be economical to change to a more efficient light.
"If your sanctuary is used only on Sunday morning and for an occasional meeting during the week, replacement is not warranted," Meyer said.
The areas within a church that could be considered for high efficiency lighting include any areas used daily. This might be the office, pastor’s study and any preschool areas within the church.
"Other areas must be considered on a case-by-case basis," Meyer said.
"There are a few symptoms that can be observed to indicate low charge," said Gene Meyer, extension specialist in small business energy at Kansas State University.
All of these symptoms can have more than one cause; so it will take a trained service person to diagnose the problem.
"If your unit is equipped with a sight glass, check to see if the glass has bubbles in it when the unit is operating," Meyer said.
Bubbles indicate either a low charge, a restriction in the condenser or other high pressure components, or incomplete condensing."
"Ice formation on one of the refrigerant lines is another symptom of low charge," Meyer said. "Again, there could be other causes."
Although, there are several causes for poor cooling, inadequate cooling is another symptom of low refrigerant.
If any of the above symptoms exist, do not arbitrarily add refrigerant.
"This can reduce efficiency or damage the air conditioner," Meyer said.
"There are few locations in Kansas where it is cheaper to operate a gas air conditioner than an electric air conditioner," said Doug Walter, president of Kansas Building Science Institute, Manhattan.
Where savings are possible, they generally are not enough to justify the higher cost of gas air conditioning equipment.
Using average Kansas summer rates for natural gas and electricity, electric air conditioning is cheaper than natural gas air conditioning if the Seasonal Energy Efficiency Ratio (SEER) of the electric unit is 9.2 or higher. (New residential gas air conditioners vary little in efficiency.)
Even though a new gas air conditioner can operate at a lower cost than most older electric air conditioners and some newer models, a mid- to high-efficiency electric air conditioner will almost always outperform a gas air conditioner and cost substantially less to purchase and install," Walter said.
"And even though high summer electric rates and low gas rates will improve the economics of gas air conditioning, it is difficult to justify the 50 to 80 percent higher initial cost over conventional electric systems," Walter said.
Two reasons why frost accumulates on refrigerant lines and reduces the cooling capacity are low refrigerant flow through the lines or reduced air flow over the cooling coil.
"You should first check your furnace air filters," said Richard B. Hayter, director of Engineering Extension at Kansas State University.
If the filters are completely loaded with dirt, the air flow through them will be restricted Similarly, if your furnace is equipped with an electrostatic air cleaner, it too may be plugged and should be cleaned.
You should check the blower on your furnace to make sure it is functioning properly," Hayter said.
If the blower is belt driven, check to see that the belt has not broken and has proper tension.
Another common cause for frosting and reduced capacity is a low refrigerant charge in the air conditioner or a restriction in the refrigerant flow. These problems can be corrected by an air conditioning service contractor.
"When the cause of the problem is corrected and the air conditioner is turned on, there may be a short time before it begins to provide satisfactory cooling," Hayter said.
Typically if the refrigerant lines have frosted, so has the evaporator or cooling coil. The frost from this coil must melt before air can flow through it. You should allow the coil to defrost before you attempt to operate the air conditioner.
"An indication that the coil in the furnace has defrosted is that the frost has melted from the refrigerant lines which lead to the air conditioner," Hayter said.
"Yes, the unit should be shut down at night and weekends, but you may need to start the unit early in the morning to bring the building to a comfortable temperature by opening time," said Gene Meyer, extension specialist in small business at Kansas State University.
A programmable thermostat can be used to do this if much time is required to cool the building.
"If the unit takes an excessively long time to bring the building down to temperature, simply setting the thermostat up 10 to 15 degrees will be almost as good as shutting it off completely, Meyer said.
"The whole-house fan provides cooling by moving a large volume of air into and through the house, typically exhausting it through the attic," said Bruce Snead, extension specialist in residential energy at Kansas State University.
You should use the fan when the outdoor air temperature is at or below the desired indoor temperature, usually during the late evening and night hours. You use the fan at night to help create more comfortable sleeping conditions without air conditioning.
"Central air conditioning cools by lowering the temperature and humidity of indoor air," Snead said.
When it is hot and humid outside, the house is closed up and the indoor air is conditioned.
"Central air conditioning and a whole-house fan should never operate at the same time," Snead said.
The best strategy may be to use the whole-house fan extensively during the late spring and early fall when the demand for cooling is rarely large and extended heat waves are unlikely. Also use the fan in the summer when temperatures and humidity are at or below normal.
"When outdoor temperatures and humidity rise to uncomfortable levels, close up the house and switch to air conditioning," Snead said.
In deciding what will be most comfortable for you, follow the weather patterns as you use one system or the other for a few days. In general, avoid using both systems every day, especially during very humid weather.
The whole-house fan may significantly raise the moisture level inside your house by bringing in outdoor air. Switching to air conditioning the next day may drop the temperature, but you will be less comfortable," Snead said.
The most economical approach is to minimize the effects of the sun's heat on your home, use fans and the whole house fan as a first choice, and switch to air conditioning when the heat and humidity become oppressive.
"There continues to be a great deal of interest in recovering energy from solid waste, though the number of waste-to-energy plants in the nation has been dropping in recent years," said William Eberle, extension specialist in land resources at Kansas State University.
"However, because the remaining plants are much larger, the volume of waste incinerated has remained about the same. The good news is that, in contrast to 25 years ago, nearly all incineration operations are used to produce energy."
Energy recovery can help make solid waste incineration an economically feasible part of an integrated waste management plan. Most waste-to-energy plants are in big metropolitan areas where large quantities of waste are generated and landfill costs are quite high. In those areas they incinerate the entire combustible part of the waste stream to generate energy, usually electricity or steam for heating.
"Mixed waste incineration presents many challenges in dealing with emissions that can affect air quality and in disposing of ash residuals, most of which will still go to landfills," Eberle said. "Overcoming these obstacles requires costly investments that can only be paid for with high volume."
In the Midwest, waste volumes and landfill costs are lower. Here, the greatest interest is in using only selected parts of the waste stream to produce energy, in some cases for individual buildings. Many medium size communities produce enough wood waste and unrecyclable paper to provide energy sufficient to heat several large public buildings. These fuels present fewer concerns relating to air quality and disposal of residual ash.
"As we learn more about small-scale waste-to-energy technology and are better able to separate parts of the waste stream, generation of energy from waste is likely to become a more important option for even medium size Midwestern cities the size of Manhattan and perhaps even smaller," Eberle said.
"For residential boilers, the storage procedure is simple," said Gene Meyer, extension specialist-mechanical engineer at Kansas State University.
"It is important that if you chemically treat the water in your boiler, the proper level of treatment exists in the boiler prior to summer storage."
In addition, steam boilers should be filled completely to prevent an air/water interface.
"If the boiler is not filled completely, a line of corrosion will form at the boiler water line," Meyer said.
"It is a good idea to tag a steam boiler to remind you to later the water level to the proper level prior to startup in the fall."