International. The increasing use of loads that are connected in buildings as well as insufficient information about how much energy they consume represent a challenge for engineers in determining how to cool a building in the best way.
A Guide to meeting this challenge is found in the new ASHRAE standard. The ASHRAE/ANSI Standard 203-2014, "Test Method for Determining Heat Gain of Office Equipment Used in Buildings," prescribes test methods to determine the range and average operational heat gain of electrical equipment for use in the calculation of thermal loads. The standard applies to loads of plug-in electrical equipment.
Plug-in loads (computers, monitors, printers, projectors, etc.) are estimated to use between 20 to 50% of the building's energy. They have evolved to become the largest percentage of the building's thermal load. Two factors are responsible for this increase, according to Glenn Friedman, chair of the Standard 203 committee.
"First, over time, the use of computers has increased, resulting in an increased number of personal computers in buildings. Second, advances in construction techniques have improved envelopes and reduced that portion of load/energy use," Friedman said.
Engineers optimize the selection of HVAC equipment by performing thermal load calculations. The heat gains of the equipment being connected are a significant part of these calculations.
"Most of the loads that are connected operate at a fraction of their rated plate electrical charge, so as a result, they produce less thermal load than engineers can use when making their load calculations based on the plate rated values," he added. "This can result in oversizing of air conditioning equipment, which carries an additional upfront cost for that equipment as well as a higher operational cost."
To acquire the standard you can enter www.ashrae.org/bookstore
