To more evenly distribute energy loads throughout the day, the open office area will have a ceiling cavity that is lined with Phase Change Materials (PCMs).
PCM technology, which can store and release energy at certain temperatures (in our case around room temperatures), can be recharged or “frozen” when energy loads (and rates) are low such as at night and during weekends. Moderately cool air leading from a dedicated duct loop from rooftop AHU is introduced into the cavity during this time, transferring energy from the freezing process of the PCMs into the air stream. Controlled dampers between the space and ceiling cavity close to ensure efficient charging of the PCMs.
Then, during peak demand office hours, these dampers are opened and a low velocity fan creates an airflow pulling room air from the center of the space into the PCM cavity and creating a cooler “air curtain” along the perimeter of the space. The PCMs “thaw” and in this process absorb energy from the warmer air into the PCMs, resulting a cool airstream entering the office space. We locate this supply stream of air right strategically close to window areas of the exterior walls. This creates a cooling curtain at the perimeter of the space reducing the median radiant temperature of a space. This not only reduces strain on the UFAD system, reducing run time and energy consumption during office hours, but also provided a highly comfortable thermal environment for occupants. The energy consumption required to cool the space is effectively shifted between day and night which can be cost beneficial in rate incentivized utility service systems.