This beta release is just like the 1.0 version with the addition of links to DOE-2.1E. Five DOE-2 output parameters at the building. DOE-2.1E Simulation.
Abstract This report documents many of the validation studies (Table 1) of the DOE-2 building energy analysis simulation program that have taken place since 1981. Results for several versions of the program are presented with the most recent study conducted in 1996 on version DOE-2.1E and the most distant study conducted in 1981 on version DOE-1.3. This work is part of an effort related to continued development of DOE-2, particularly in its use as a simulation engine for new specialized versions of the program such as the recently released RESFEN 3.1. RESFEN 3.1 is a program specifically dealing with analyzing the energy performance of windows in residential buildings. The intent in providing the results of these validation studies is to give potential users of the program a high degree of confidence in the calculated results. Validation studies in which calculated simulation data is compared to measured data have been conducted throughout the development of the DOE-2 program.
Discrepancies discovered during the course of such work has resulted in improvements in the simulation algorithms. Table 2 provides a listing of additions and modifications that have been made to various versions of the program since version DOE-2.1A. One of the most significant recent changes in the program occurred with version DOE-2.1E. An improved algorithm for calculating the outside surface film coefficient was implemented. In addition, integration of the WINDOW 4 program was accomplished resulting in improved ability in analyzing window energy performance. Validation and verification of a program as sophisticated as DOE-2 must necessarily be limited because of the approximations inherent in the program.
For example, the most accurate model of the heat transfer processes in a building would include a three-dimensional analysis. To justify such detailed algorithmic procedures would correspondingly require detailed information describing the building and/or HVAC system and energy plant parameters. Until building simulation programs can get this data directly from CAD programs, such detail would negate the usefulness of the program for the practicing engineers and architects who currently use the program. In addition, the validation studies discussed herein indicate that such detail is really unnecessary. The comparison of calculated and measured quantities have resulted in a satisfactory level of confidence that is sufficient for continued use of the DOE-2 program. However, additional validation is warranted, particularly at the component level, to further improve the program. A study is described which collected data developers can use to validate the algorithms used by building energy analysis computer programs to model system and central plant performance of typical heating, cooling, and ventilating (HVAC) systems.
Building energy analysis programs compute (1) loads imposed on building environmental control systems for each zone, (2) loads imposed on central equipment (using the zone loads and system performance algorithms), and (3) the primary energy demanded by the central- and zone-specific components. The information collected during this study made it possible to compare actual system performances with computer-generated results of system performances. In addition, this study identified some problems common to HVAC systems, including (1) often unreliable controls performance such as drifting away from calibration and poor repeatability, and (2) as-delivered components which do not operate at manufacturers' specifications. This document describes the Army's energy criteria (prescriptive standards and energy budgets) and compares them with the information contained in a BLAST input deck.
DOE-2
Since most of the information needed to review a new design for compliance with energy criteria is in the BLAST input deck, a special BLAST Design Review Summary report was developed which provides, in an easy-to-read standard format, the information needed to check a design for energy criteria compliance. This document also describes how the BLAST Design Review Summary report can be used by U.S.
Army Corps of Engineers districts to review the energy effectiveness of new facility designs submitted by architect/engineer firms. The pros and cons of alternative methods for doing design reviews which do not require the use of BLAST are also discussed. The purpose of this study is to evaluate and validate the effects of SECP on energy consumption.
The evaluation and validation of a State's energy conservation plan require an in-depth examination of all phases of the plan. A workbook and a set of questions for each State were prepared and presented to DOE in January 1979.
This workbook details our understanding of the 1979 and 1980 energy savings estimation methodologies, data sources and assumptions as of that time was prepared as a focal point for further study. Portions of New York's SECP workbook entitled Primary Program Measures of the New York State Energy Conservation Plan are attached to this executive summary. Bell Hall (Building No. Leavenworth, constructed in 1957, has undergone one major addition completed in 1986.
Comparison Of Doe-2.1E
Bell Hall is primarily used for officer training, which was its original intent. Over the years, equipment loads within the facility have increased, mainly due to increased computer usage. The original construction of this facility did not anticipate the additional computer load and the present mechanical and electrical systems are undersized. The systems are not capable of providing cooling all year; which is a requirement for the new computers. Since it`s implementation, the HVAC systems have had problems maintaining environmental control.
Saving energy and improving environmental control at the same time for this facility will be a difficult task. Many of the systems don`t maintain the minimum temperature and ventilation levels in the building and are shut down most of the time. Modifying these systems to use less energy will require construction modifications to allow proper operation. This increased the cost of the EGO`s and made reasonable paybacks difficult to achieve.
This section deals with the determination of heating equipment efficiencies, thermal distribution (air or hydronic) efficiencies, infiltration, and thermostat management. The energy consumption for most types of heating and cooling equipment is estimated using the DOE-2 building simulation program (version 2.1E), developed by the U.S. Department of Energy (Birdsall et al., 1990). A companion report (Warner 2005) describes the thermodynamic modeling of the home, and the relevant characterizations of the building’s thermal envelope (windows, insulation, etc.) The program performs a sophisticated series of calculations, modeling the energy consumption in the user’s house in a full annual simulation for a typical weather year (involving 8760 hourly calculations).
Users can choose from approximately 293 weather locations around the United States. More details about the DOE-2 model and documentation of the current input file are provided Energy use for some heating and cooling equipment types are estimated independently of DOE-2 and are documented in this report. Interactions between space-conditioning equipment and the waste heat from occupants and appliances are also treated in the modeling process. User inputs (or defaulted values, where user-entered values aren’t available) are gathered together and sent to the DOE 2.1E model to calculate the heating and cooling (and water heating if user specified that water heating was tied to a central boiler system) energy consumption.