Zero net energy (ZNE) buildings of different types have been designed and verified in various climates. However, as California, New York, and other states and jurisdictions march towards commercial new construction ZNE goals, for most buildings this target remains illusory. While state energy codes have taken great strides in improving energy efficiency requirements for buildings, efficiency levels are reaching an asymptote under today's prescriptive compliance path. To accelerate adoption of best practices, energy codes should provide compliance paths for newer technologies that offer performance improvements under an integrated design strategy as opposed to the traditional approach of incorporating the lowest common denominator. Energy codes should focus on whole building performance while permitting, if not promoting, high performance designs that go beyond component efficiencies. While impacts of climate on building design are embedded in code requirements, energy codes do not often incorporate design requirements and constraints of specific building types into required efficiency levels. Energy efficiency criteria for specific building types can help promote cost-effective improvements better aligned with industry practices. For example, warehouse buildings offer tremendous opportunities to achieve ZNE in the near term, but there is little direction for designers to achieve such targets. Recent ASHRAE Advanced Energy Design Guides for ZNE buildings highlight the importance of providing guidance for specific building types. Stretch Codes, such as recently developed by New York, provide enforceable mechanisms for higher building performance levels. Progressive cities can adopt them to serve as "proving grounds". They provide forward-looking steps that states may take one or two code cycles ahead of current requirements, acting as a signal to industry. Zero net energy buildings require concrete energy performance targets, and focusing on building types most feasible for zero net energy will help move ZNE out of the niche realm and closer to code.

Author(s): Nordman, Bruce; Kloss, margarita; Kundu, Bijit; Dewart, nate; Prakash, Anand; Wong, laura; torres, Alanna; Levine, Rachel; Pritoni, Marco; Shackleford, Jordan; werner, Heidi; Athalye, Rahul; Khandekar, Aditya; Clark, Callie; uraine, Chris; Aviles, Rebecca | Abstract: Energy reporting is the principle that all energy-using devices in buildings should be able to track their own energy use and report this to the local network. Energy reporting can provide building owners with easy access to highly granular energy use data. This report makes the case that energy reporting should become a free basic feature of all devices, and reports on a project intended to move us towards that goal. The project collected a set of demonstration devices with energy reporting features, including products that were modified by the project team or the manufacturer, or are already available for sale. To show these devices operating live at meetings and conferences, the team created a management system that queries the energy reporting devices for their data, stores the data, and displays it in compelling visualizations. The devices covered a wide range, including heating, ventilation, and air conditioning (thermostat and air purifier); lighting (individual bulb, task light, and auto-dimming overhead light); a vehicle charger; a water heater; electronics (notebook personal computer and universal serial bus charger); and three external meters (one integral with a dimming light switch). The demonstration uses a variety of communication protocols. The report reviews existing communication protocols that support energy reporting and describes how to use them with a proposed reference data model for energy reporting. It also assesses ways that energy codes and standards processes can be leveraged to drive energy reporting technology into the market. Energy reporting could ultimately save California on the order of 2.5 terawatt-hours per year and about $0.8 billion per year. Energy reporting is a highly practical technology with minimal (sometimes no) cost to consumers and manufacturers. This report discusses creation of the energy reporting devices themselves, analysis and recommendations for data models and protocols for energy reporting, and energy codes and standards implications of energy reporting technology. While energy reporting does not directly save energy, it provides information for better decision-making to save energy in changing equipment operation, maintenance, and replacement.

ANSI/ASHRAE/IES Standard 90.1 is the U.S. national commercial building model energy code and it has a significant impact on many programs and policies that impact energy savings across the United States and the world. Determining the energy savings from the latest edition of Standard 90.1 relative to previous editions is critical for beyond code programs and for others setting energy performance targets. Pacific Northwest National Laboratory developed prototype building models to determine the energy savings from 90.1-2016 standard. This paper presents the rigorous modeling and development process that PNNL has established and its applications. In addition, the energy savings results of Standard 90.1-2016 are described.

This report describes and analyzes a set of energy efficiency measures that will save 20% energy over ASHRAE Standard 90.1-2013. The measures will be used to formulate a Reach Code for cities aiming to go beyond national model energy codes. A coalition of U.S. cities together with other stakeholders wanted to facilitate the development of voluntary guidelines and standards that can be implemented in stages at the city level to improve building energy efficiency. The coalition's efforts are being supported by the U.S. Department of Energy via Pacific Northwest National Laboratory (PNNL) and in collaboration with the New Buildings Institute.

To meet statutory requirements, DOE conducted an analysis to quantify the expected energy savings associated with Standard 90.1-2016. This report documents the methodology used to conduct the analysis. Based on the analysis, DOE has determined that the 2016 edition of the ANSI/ASHRAE/IES Standard 90.1 would improve overall energy efficiency in buildings subject to the code compared to the 2013 edition of Standard 90.1.

Depending on the application, the complexity of an HVAC system can range from a small fan coil unit to a large centralized air conditioning system with primary and secondary distribution loops, and central plant components. Currently, the taxonomy of HVAC systems and the components has various aspects, which can get quite complex because of the various components and system configurations. For example, based on cooling and heating medium delivered to terminal units, systems can be classified as either air systems, water systems or air-water systems. In addition, some of the system names might be commonly used in a confusing manner, such as "unitary system" vs. "packaged system." Without a systematic classification, these components and system terminology can be confusing to understand or differentiate from each other, and it creates ambiguity in communication, interpretation, and documentation. It is valuable to organize and classify HVAC systems and components so that they can be easily understood and used in a consistent manner. This paper aims to develop a systematic classification of HVAC systems and components. First, we summarize the HVAC component information and definitions based on published literature, such as ASHRAE handbooks, regulations, and rating standards. Then, we identify common HVAC system types and map them to the collected components in a meaningful way. Classification charts are generated and described based on the component information. Six main categories are identified for the HVAC components and equipment, i.e., heating and cooling production, heat extraction and rejection, air handling process, distribution system, terminal use, and stand-alone system. Components for each main category are further analyzed and classified in detail. More than fifty system names are identified and grouped based on their characteristics. The result from this paper will be helpful for education, communication, and systems and component documentation.

The U.S. Department of Energy (DOE) Building Energy Codes Program (BECP) periodically evaluates national and state-level impacts associated with energy codes in residential and commercial buildings. Pacific Northwest National Laboratory (PNNL), funded by DOE, conducted an assessment of the prospective impacts of national model building energy codes from 2010 through 2040. A previous PNNL study evaluated the impact of the Building Energy Codes Program; this study looked more broadly at overall code impacts. This report describes the methodology used for the assessment and presents the impacts in terms of energy savings, consumer cost savings, and reduced CO2 emissions at the state level and at aggregated levels. This analysis does not represent all potential savings from energy codes in the U.S. because it excludes several states which have codes which are fundamentally different from the national model energy codes or which do not have state-wide codes. Energy codes follow a three-phase cycle that starts with the development of a new model code, proceeds with the adoption of the new code by states and local jurisdictions, and finishes when buildings comply with the code. The development of new model code editions creates the potential for increased energy savings. After a new model code is adopted, potential savings are realized in the field when new buildings (or additions and alterations) are constructed to comply with the new code. Delayed adoption of a model code and incomplete compliance with the code’s requirements erode potential savings. The contributions of all three phases are crucial to the overall impact of codes, and are considered in this assessment.

The Energy Policy Act of 2005 (EPACT 2005) required energy use in Federal buildings to be metered. Since then, the US Army has installed electricity and natural gas meters on new and many existing facilities. A centralized Metering Data Management System (MDMS) was put into place to collect and store metered data from Army installations. Benchmarks are needed to characterize energy performance using the metered data. The US Army Corps of Engineers (USACE) in collaboration with Pacific Northwest National Laboratory (PNNL) developed energy consumption benchmarks to put metered performance into context. The intent was to help energy managers, who are often short on resources while managing hundreds of buildings, to understand the performance of their buildings. This paper describes the methodology behind the development of energy consumption benchmarks for five common Army buildings. Calibrated energy models are used to develop the benchmarks. By using calibrated models the actual operation of buildings for a given location is captured. The paper describes the advantages and disadvantages of the approach, and summarizes ways in which baseline models can be used and how they can benefit MDMS users.

Editor's Note: ANSI/ASHRAE/IES Standard 90.1, Energy Standard for Buildings Except Low-Rise Residential Buildings, has been a benchmark and national model code for commercial buildings for over 35 years and indispensable for engineers and other professionals involved in the design of buildings and building systems. Now, with well over 100 addenda incorporated since the 2013 edition, Standard 90.1-2016 will significantly change the way buildings are built as these new modifications find their way into the world's energy codes.

A more recent period of weather data published in the ASHRAE 2009 Handbook of Fundamentals was used in developing ASHRAE Standard 169-2013. The new Standard remapped counties to climate zones based on the new weather data. More than 400 counties out of a total of over 3,000 in the U.S. were reassigned to different climate zones and most of the counties were reassigned to warmer climate zones. Many code requirements, such as for wall insulation, are less stringent in warmer climate zones. Thus, when a county is reassigned to a warmer climate zone, new buildings built in that county are likely to be less energy efficient than before. The new county-to-climate zone mapping in ASHRAE Standard 169-2013 has been adopted by Standard 90.1 and may be adopted by other codes and standards as well. In this paper, we present the impact of changing the county-climate zone mapping on energy codes and building energy efficiency in the country. The analysis shows that adopting the new county-to-climate zone mapping in ASHRAE Standard 169-2013 results in an overall weakening of ASHRAE Standard 90.1-2013 at the national level while the impacts at the state level can be dramatic, as there are several states where large population centers are reassigned to a warmer climate zone.

Building energy codes have significantly increased building efficiency over the last 38 years, since the first national energy code was published in 1975. The most commonly used path in energy codes, the prescriptive path, appears to be reaching a point of diminishing returns. The current focus on prescriptive codes has limitations including significant variation in actual energy performance depending on which prescriptive options are chosen, a lack of flexibility for designers and developers, the inability to handle optimization that is specific to building type and use, the inability to account for project-specific energy costs, and the lack of follow-through or accountability after a certificate of occupancy is granted. It is likely that an approach that considers the building as an integrated system will be necessary to achieve the next real gains in building efficiency. This report provides a high-level review of different formats for commercial building energy codes, including prescriptive, prescriptive packages, capacity constrained, outcome based, and predictive performance approaches. This report also explores a next generation commercial energy code approach that places a greater emphasis on performance-based criteria.

Moving to the ASHRAE Standard 90.1-2013 (ASHRAE 2013) edition from Standard 90.1-2010 (ASHRAE 2010) is cost-effective for the District of Columbia. The table below shows the state-wide economic impact of upgrading to Standard 90.1-2013 in terms of the annual energy cost savings in dollars per square foot, additional construction cost per square foot required by the upgrade, and life-cycle cost (LCC) per square foot. These results are weighted averages for all building types in all climate zones in the state, based on weightings shown in Table 4. The methodology used for this analysis is consistent with the methodology used in the national cost-effectiveness analysis. Additional results and details on the methodology are presented in the following sections. The report provides analysis of two LCC scenarios: Scenario 1, representing publicly-owned buildings, considers initial costs, energy costs, maintenance costs, and replacement costs—without borrowing or taxes. Scenario 2, representing privately-owned buildings, adds borrowing costs and tax impacts.

The purpose of this analysis is to examine the cost-effectiveness of the 2013 edition of ANSI/ASHRAE/IES Standard 90.1 (ANSI/ASHRAE/IES 2013). PNNL analyzed the cost-effectiveness of changes in Standard 90.1 from 90.1-2010 to 90.1-2013, as applied in commercial buildings across the United States. During the development of new editions of Standard 90.1, the cost-effectiveness of individual changes (addenda) is often calculated to support the deliberations of ASHRAE Standard Standing Project Committee (SSPC) 90.1. The ASHRAE process, however, does not include analysis of the cost-effectiveness of the entire package of addenda from one edition of the standard to the next, which is of particular interest to adopting State and local governments. Providing states with an analysis of cost-effectiveness may encourage more rapid adoption of newer editions of energy codes based on Standard 90.1. This information may also inform the development of future editions of Standard 90.1.

Advanced Energy Design Guides (AEDGs) were originally developed intended to provide a simple approach to building professionals seeking energy efficient building designs better than ASHRAE Standard 90.1. Since its first book was released in 2004, the AEDG series provided inspiration for the design industry and were seen by designers as a starting point for buildings that wished to go beyond minimum codes and standards. In addition, U.S. Department of Energy’s successful Commercial Building Partnerships (CBP) program leveraged many of the recommendations from the AEDGs to achieve 50% energy savings over ASHRAE Standard 90.1-2004 for prototypical designs of large commercial entities in the retail, banking and lodging sectors. Low-energy technologies and strategies developed during the CBP process have been applied by commercial partners throughout their national portfolio of buildings. Later, the AEDGs served as the perfect platform for both Standard 90.1 and ASHRAE’s high performance buildings standard, Standard 189.1. What was high performance a few years ago, however, has become minimum code today. Indeed, most of the prescriptive envelope component requirements in ASHRAE Standard 90.1-2013 are values recommended in the 50% AEDGs several years ago. Similarly, AEDG strategies and recommendations have penetrated the lighting and HVAC sections of both Standard 189.1more » and Standard 90.1. Finally, as we look to the future of codes and standards, the AEDGs are serving as a blueprint for how minimum code requirements could be expressed. By customizing codes to specific building types, design strategies tailored for individual buildings could be prescribed as minimum code, just like in the AEDGs. This paper describes the impact that AEDGs have had over the last decade on the design industry and how they continue to influence the future of codes and Standards. From design professionals to code officials, everyone in the building industry has been affected by the AEDGs.« less