Team: Sustainability Savants
Overview
The climate in the Washington DC metro area is characterized by warm, humid summers; together with the stringent temperature and humidity requirements for the collections areas, this presents a significant challenge in designing an efficient system, with the target being minimizing energy usage (and thereby energy costs as well). In developing the model of the existing facility, the air system, with its large supply volume and high static pressure, was noted as the primary source of energy usage, between fan energy and space conditioning.
The approach taken, then, was to reduce loads in the collections spaces as much as possible, with the goal being to enable supply of only required ventilation air. Improving the insulation between the office and storage bays, and shading both the western façade and roof, reduce conductive gains. Infiltration is reduced by construction of vestibules around the external doorways for the storage bays, as well as an operational emphasis on never having a direct air path from either office or external air into the collections. Internal gains are relatively minor, but reducing the lighting gains via LED lighting with data center-style “follow me” occupancy sensing controls greatly lessens any additional cooling load.