Search results
Results from the WOW.Com Content Network
The COP of absorption chillers can be improved by adding a second or third stage. Double and triple effect chillers are significantly more efficient than single effect chillers, and can surpass a COP of 1. They require higher pressure and higher temperature steam, but this is still a relatively small 10 pounds of steam per hour per ton of cooling.
The above efficiency formulas are based on simple idealized mathematical models of engines, with no friction and working fluids that obey simplified thermodynamic models. Real engines have many departures from ideal behavior that waste energy, reducing actual efficiencies below the theoretical values given above. Examples are: friction of ...
The SEER rating of a unit is the cooling output during a typical cooling-season divided by the total electric energy input during the same period. The higher the unit's SEER rating the more energy efficient it is. In the U.S., the SEER is the ratio of cooling in British thermal units (BTUs) to the energy consumed in watt-hours.
This factor is used to represent the temperature difference between indoor and outdoor air with the inclusion of the heating effects of solar radiation. [1] [5] The second factor is the CLF, or the cooling load factor. This coefficient accounts for the time lag between the outdoor and indoor temperature peaks.
Window insulation reduces heat transfer from one side of a window to the other. The U-value is used to refer to the amount of heat that can pass through a window, called thermal transmittance, with a lower score being better. [1] The U-factor of a window can often be found on the rating label of the window.
For example, in a scenario where the actual temperature is 10 degrees but the "feels like" temperature is -5 degrees, what that really means is that the wind chill is making it feel as if the air ...
The frame and double sealing of the window system are the actual weak points in the window insulation. Typical thermal transmittance values for common building structures are as follows: [citation needed] Single glazing: 5.7 W/(m 2 ⋅K) Single glazed windows, allowing for frames: 4.5 W/(m 2 ⋅K) Double glazed windows, allowing for frames: 3.3 ...
A typical installation of insulated glass windows with uPVC frames. Possibly the earliest use of double glazing was in Siberia, where it was observed by Henry Seebohm in 1877 as an established necessity in the Yeniseysk area where the bitterly cold winter temperatures regularly fall below -50 °C, indicating how the concept may have started: [2]