City Reach Code Technical Support Document

Abstract

The Architecture 2030 organization gathered a coalition of U.S. cities together with other stakeholders to facilitate the development of voluntary guidelines and standards that could be implemented in stages at the city level to improve building energy efficiency. This coalition sought technical support from the U.S. Department of Energy (DOE) for the development of these guidelines. Pacific Northwest National Laboratory (PNNL), funded under DOE's Building Energy Codes Program (BECP), provided this technical support to the coalition in collaboration with New Buildings Institute (NBI). These guidelines will be formed around a set of increasingly stringent performance metrics, starting from a 20% improvement over existing model energy codes to a policy that delivers net-zero energy performance. The focus of this project is the 20% improvement over existing commercial model energy codes.NBI and PNNL assembled a set of energy-efficiency measures (EEMs) that would have the potential to deliver 20% energy savings over ASHRAE Standard 90.1-2013, which was chosen as the baseline model energy code for this project. The EEMs were developed using several sources including national model codes and standards, high-performance building codes and standards, regional energy codes, and measures that are being proposed as part of the on-going code development process. The EEMs improved all aspects of building design that are traditionally defined to be within the scope of energy codes, including, opaque envelope and fenestration, air leakage, interior and exterior lighting power, occupancy sensors, fan power, HVAC equipment efficiency, HVAC controls, service hot water waste heat recovery, plug load control, daylighting, and others.Energy savings from the chosen EEMs were estimated using PNNL-developed prototype building models, which are whole building energy models built using DOE's EnergyPlus software. Five prototypes were selected for this analysis based on the typical proportion of building types in U.S. cities: High-rise Apartment, Large Hotel, Large Office, Secondary School, and Stand-alone Retail. These prototypes were simulated in six climate zones: 2B (hot, dry), 3A (warm, humid), 3C (warm, marine), 4A (mixed, humid), 4C (mixed, marine), and 5A (cool, humid). Individual EEMs were applied separately to the selected prototypes and climate zones to determine energy savings. EEMs were then combined into bundles to incorporate interactive effects and to determine the total impact of all EEMs.The results show that with the group of EEMs described in this report, it is possible to achieve 20% energy savings over Standard 90.1-2013 in nearly all building types and climate zones analyzed in this study. v

Energy Savings Analysis of the Proposed NYStretch-Energy Code 2018

“…The stretch code measures were developed by PNNL, New Buildings Institute (NBI), and NYSERDA with several rounds of reviews discussions with the stretch code advisory group, commercial working group, and multifamily working group members. Several sources contributed to the compilation of the EEM list, (Athalye et al 2017). Recommended EEMs are listed in Table 5.…”