Design of Energy Efficient Buildings. Applied on HVAC Systems in Commercial Buildings

Doctoral thesis, 1996

A methodology for planning and design of energy efficient buildings is presented and analysed. The starting point is the definition that energy efficiency is a question of minimizing the energy end-use within realistic economic frames and fully preserved function. The methodology is based on a systematic approach to the issue of energy efficiency. One element in this is the introduction of a number of energy related ratios, Energy Performance Ratios, that characterise the influence of building parts and the technical systems of the building on the energy end-use of the building as an entirety. These ratios are selected and formulated so that they facilitate a systematic strive towards high energy efficiency when applied in planning and design of buildings. One basic moment is to elucidate the energy interaction between different parts and systems of the building in order make it easier to avoid sub-optimised solutions. This is done by introducing an imaginary division of the building into, from an energy end-use point of view, characteristic system parts on different levels of interaction with other parts. The build up of the Energy Performance Ratios follows this division. Therewith the application of these ratios contributes to a comprehensive view when designing the building. Another basic moment is the setting of Energy Targets to aim at when building parts, technical systems and components are designed and rated. This is done by quantifying the Energy Performance Ratios. A substantial part of the work deals with the quantification of Energy Performance Ratios to realistic Energy Targets. This is done by a combination of analyses of existing monitored buildings and theoretical simulations and calculations. In the present work the methodology is applied primarily on design and rating of heating, ventilation and air-conditioning systems with a focus on commercial buildings. However, the methodology itself is not meant to be limited to these applications. The basic idea is that it should be applied on all the parts of the building that have an obvious influence on the energy end-use.