When it comes to making energy-efficient choices, facility managers and others in the field have a wealth of resources at their fingertips. Unfortunately, not all of the information that is readily available on the web is accurate. Here are 3 myths that did not pass fact-checking.
Myth: Energy management and maintenance plans should be separate.
Fact: Segregated energy management and maintenance plans can cause financial and energy waste. A good example of how the two plans go hand-in-hand is thinking of how an upgrade in lighting will affect the load on the HVAC system, which is the example used in this Building’s magazine article.
Myth: A lower window-to-wall ratio will conserve energy.
Fact: Though it is true that windows do not insulate as well as walls, having a lower window-to-wall ratio does not necessarily mean that a building will conserve more energy. There are multiple factors to consider when assessing energy conservation in terms of windows versus walls. For example, daylighting is a common practice that conserves electrical energy by using natural light (mostly from windows) during the day.
In fact, a change to ASHRAE Standard 90.1 that would have reduced the maximum window-to-wall ratio from 40% to 30% was recently appealed because of lack of evidence that a lower window-to-wall ratio will conserve energy.One way to increase window energy efficiency no matter the window-wall-ratio is to retrofit windows with architectural window films. The latest window film technology can often increase a standard window’s insulating power by as much as 92% and can typically provide year-round energy savings.
MythMore heating energy will be required to bring a building back to normal temperature in the morning than will be saved if you set the thermostats down at night.
FactContrary to the belief by some, adjusting the set points on HVAC systems by even a few degrees at night can have a large impact on heating and cooling costs. These savings more than offset the energy required to “recover” from such adjustments.
According to the Washington State University’s “Energy Experts” website, commercial buildings can save about 1% on energy costs for each degree the thermostat is lowered in the winter and raised in the summer, for each 8 hour period. Savings as a percentage of heating and cooling bills will be greater in mild climates than in more severe climates. Therefore, reducing the heating setpoint from 70 deg F to 60 deg F each night, would save approximately 10% on heating costs. Similarly, increasing the setpoint for cooling at night from 75 deg F to 85 deg F would save about 10% on cooling costs.
© 1995-2012 Trade Press Media Group, Inc.
Building Operating ManagementMaintenance SolutionsArticle DirectoryTopics
Contact UsPoliciesManage Email