October 11, 2024

Energy Performance and Analysis Process – Douglaston/Little Neck Queens Public Library

This post is the first in a series that will highlight our integrated design toolkit used to design a new public library to serve the Douglaston–Little Neck neighborhood of Queens. Part 1 highlights the project’s performance analysis that was used to inform the schematic design development.

Located on a prominent corner site, the new library will capitalize on the site’s inherent opportunities: the main program spaces are visible to the street, making the range of services and activities clear and legible; the design aims to provide daylight to all spaces, includes an occupiable rooftop garden, and is sited to maximize street level outdoor space to create a welcoming and gracious entrance. The library will be a distinguished center for activity and a beacon for the community. Careful manipulation of fenestration is designed to bring daylight to most spaces while mitigating glare. In addition, the building features highly insulated walls and roof, an all-electric mechanical system, rooftop solar panels, and an advanced air filtration system. When complete, the project will attain LEED Gold certification.

Early in design, BKSK developed three schemes to identify which would best align with the libraries programmatic and sustainability goals. Each design scheme is oriented around the creation of a new main entrance area that provides visibility to the main spaces.

Our design team hosted several workshops with the library stakeholder to craft an owner’s project requirements document that formalizes the goals of the project, defines operational requirements, and identifies pathways to achieve energy reduction targets. During schematic phase, the team performed a sensitivity analysis to test energy performance, daylight quality, visual comfort, and quantify embodied carbon calculations which also attempted to overlay local law compliance with certain targeted LEED credits. This type of study is considered “sensitivity analysis”, where the design team tests the operational performance of each scheme with a series of façade parameters.

Massing and Envelope Sensitivity Analysis

The purpose of this early energy analysis is to compare the performance of the three schematic design options. All options have the same square footage, however the massing strategy, façade exposure, compactness, window to wall ratio, and floor counts vary. This model serves as the initial starting point to establish the Site Energy Use Intensity (EUI) and test numerous facade parameters, identifying opportunities and deficiencies. The above charts demonstrate the incremental energy savings of various thermal improvements to the building’s thermal envelope.

Our team also analyzed scenarios for rooftop photovoltaics at this time to compare operational consumption with on-site electrical production. The diagrams above outline several photovoltaic array scenarios within each option and quantify their potential power contribution.

In the next post, we will share daylight and glare investigations that were used in the development of the selected scheme.