Energy engineers designing laboratory supply systems now have numerous opportunities for better contamination control and energy efficiency than in the past. More than 60 percent of the energy consumed by a conventional lab or cleanroom is used to circulate air and to supply heating, cooling, humidity, and clean air, so energy-efficient designs can result in substantial savings. Generally, annual supply system energy costs are ranked from highest to lowest as follows:
In the case of cleanrooms, the energy consumed by humidification and heating varies depending on climatic conditions and can shift from season to season. In large, specialized cleanrooms (Class 1000 and cleaner), the largest amount of energy, aside from that used for manufacturing equipment, is to supply vertical unidirectional air flow.
This chapter looks at four areas of supply systems that should be considered for energy efficiency:
·Air-Handling Units, and
We analyze these categories separately; however, design decisions for one category affect the energy use of the others, so the cumulative effects of interactions among them must be considered. [Takenami et al., 1989; Brown, 1990; Naughton, 1990a; Naughton, 1990b]