Consulting Specifying Engineer Jan/Feb 2015-CSE : Page-35

are not breakthrough innovations—in fact, they existed in niche markets prior to widespread acceptance. This concept could be applied to the emergence of variable frequency drives (VFDs) and permanent magnetic ac (PMAC) motors for use in building systems. VFDs have been used for a significant amount of time in situations where controllability was as much a driving factor as energy savings, such as in variable air volume (VAV) air handling systems. However, energy codes, such as ASHRAE Standard 90.1: Energy Standard for Buildings Except Low-Rise Residential Buildings and the International Energy Conservation Code (IECC), have redefined design priorities by emphasizing energy-saving aspects of their use. This emphasis only becomes more pronounced with improvements to the baseline energy model in each code revision cycle. The commercial baseline model in ASHRAE Standard 90.1-2010 (IECC-2012) represents a 30% improve-ment over ASHRAE 90.1-2004 (IECC-2006). The 2013/2015 code update is expected to produce an additional 8.7% energy cost improvement. The federal government has acted as the primary catalyst for this emphasis on energy. The Energy Policy and Conserva-tion Act of 1975 (EPCA-1975), with sub-sequent major amendments by the Energy Policy Act of 1992 (EPAct-1992) and the Energy Independence and Security Act of 2007 (EISA-2007), has given the Dept. of Energy wide-ranging power in mandating energy efficiency standards. While fed-erally mandating energy efficiency may sound intrusive on the surface, the process of adopting new standards does have a reasonable set of formal evaluation crite-ria, many of which are readily applicable to engineering design. The seven criteria based on EPCA legislation are: 1. Economic impact on manu-facturers and consumers: Will implementing the standard cause unusual hardship for manufactur-ers or consumers? Is the initial first cost of implementation afford-able? Figure 1: One emerging application for permanent magnet ac (PMAC) motors is in cooling towers. This picture shows a 20-hp totally enclosed, air over (TEAO) PMAC motor directly coupled to the fan instead of using a typical belt drive or gearbox; the view is from inside a cooling tower. This particular tower is a two-cell cooling tower with 3,000 gpm total capacity. The photo is looking up at a low-speed high-volume fan at the top of the tower. Elimination of the gearbox dramatically improves the efficiency and reduces maintenance requirements. All graphics courtesy: McGuire Engineers 2. Lifetime operating cost savings compared to increased cost for the product: What is the payback period? What is the lifecycle cost analysis? 3. Energy savings resulting from implementation: Quantify the magnitude of energy savings if implemented; a national-level con-sideration. 4. Lessening of utility or perfor-mance of products: Given the function, is this a misapplication of the technology? Am I attempt-ing to tow a trailer with a Fer-rari? 5. Impact of any lessening of com-petition: Is this simply adopting typical “best in class” products or something proprietary that could cause a monopoly? 6. Need for national energy con-servation: Again, a national-level consideration. Will the standard provide improvements to the secu-rity and reliability of the nation’s energy system? 7. Other factors that the Secretary of Energy considers relevant: General considerations include envi-ronmental and employment impact to the country. Will emergence of 35 Consulting-Specifying Engineer • JANUARY/FEBRUARY 2015

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