Performance-based design: HVAC systems

摘要

At its essence, all engineering design is performance-based. If we don't have a performance goal, what are we aiming for? Measuring our success against? How do we even start without such a goal? What are we getting at within the topic of performance-based heating, ventilation and air conditioning design? In current parlance, performance-based HVAC design covers three broad spectrums: 1. Design solutions that do not meet prescriptive code/standard approaches or requirements; e.g., energy cost budget design under ASHRAE 90.1: Energy Standard for Buildings Except Low-Rise Residential Buildings. 2. Design to specific metrics that may be viewed as nonstandard; e.g., designing to meet specific indoor air quality criteria. 3. Operational performance targets; e.g., designing to a specific energy use intensity target. The first spectrum is likely the one most engineers are familiar with - at one time or another most mechanical, electrical or plumbing engineers have either done this or run into it as a potential hurdle in design aspirations. Energy code prescriptive requirements are generally the most common aspect that warrants exploration of performance-based alternatives.