Sustainable Building Technical Manual - Etn-presco.net

ASHRAE STANDARDS UNDER REVISIONEnergy-Efficient Design of New Buildings—90.1-1989The new version of this standard entails a complete revision that will incorporate life-cycle factors. Two tiers ofenergy design are included. Tier 1 is more conventional and will provide for approximately 25 percent higherenergy efficiency than the 1989 version of the standard. Tier 2 is for utility rebate programs and higher-thancodeperformance levels and will provide for 50 percent higher energy efficiency than the 1989 version. Therevised standard was scheduled to be issued for public review in early 1996.Ventilation for Acceptable Indoor Air Quality—62-1989.Ventilation rates in this updated standard will be revised for densely and sparsely occupied spaces. Ventilationcalculations will take into consideration the number of occupants and building components that contribute tosource contaminants. The standard was expected to be issued for public comment in spring 1996.Thermal Environmental Conditions for Human Occupancy—55-1992A standing standard project committee (SSPC) has been recently formed for the purpose of maintaining andrevising the standard to conform with new technology as it develops.Figure 3tion of the effect of architectural design on energy use, peak loads, and other performancevariables. The goal is to determine design and system solutions that yield energy savingswithin project budgets, and thus provide positive cash flows over the life of the incrementalinvestment.During the previous decade, energy software development concentrated on upgradingexisting algorithms to properly model solar energy systems, daylighting, thermal storage,and other emerging technologies and systems. 12 More recently, load-calculation softwarehas replaced the utilization of tables. The increased capability of computers is enablingthe use of hourly energy simulation software and sophisticated analysis for all buildingtypes. Energy software tools have moved away from line input-based user interfaces toWindows-based interfaces, and computer-assisted design (CAD) systems now includeextensive databases and object-oriented graphics. The following sections describe severalsoftware programs currently in use or under development. (Additional information is providedin the “Resources” sections of Chapters 9, 10, 11, and 12.)DOE-2.1EDOE-2 is a public-domain computer program for energy analysis developed byLawrence Berkeley National Laboratory (LBNL), a DOE laboratory operated by theUniversity of California. Well-suited for large commercial buildings, the program calculatesa building’s energy use and life-cycle costs based on its location, construction,operation, and HVAC systems. It is useful in evaluating building system design, buildingretrofits, energy budgets, and life-cycle costs and benefits. The program can exploretrade-offs between design alternatives and allows for performance of detailed parametricstudies of building system variations to allow designers to increase savings andreduce first costs.DOE-2.1E, released in January 1994, includes four main calculation sections: loads, systems,plant, and economics. The program calculates the hourly heating and coolingloads for up to 128 zones. It uses hourly weather data and incorporates thermal-storageeffects of building elements. It also simulates select daylighting systems and electriclightingcontrols.