IBPSA2013

The project “Aktivhaus“-residential estate in Kramsach focuses on (1) energetic aspects and measures to reach the “net-zero-energy-building” and (2) avoidance of low indoor air humidity in winter by using the moisture buffer capacity of loam. The latter is discussed in this paper and results are presented. This investigation includes laboratory measurements on material scale for the characterization of the used loam (sorption isotherm, diffusion resistance). Cross-validation of the building simulation model Dynbil with its hygrothermal wall model is conducted.

This paper presents dynamic sensitivity analysis as a novel design analysis tool for dealing with time-varying performance aspects in the built environment. We highlight some of the limitations of conventional sensitivity analyses in building design and present dynamic sensitivity analysis as an alternative solution. The first part of this paper introduces the basic principles of dynamic sensitivity analysis. In the second part, we illustrate its potential in a simulation-based case study of a typical office zone with external solar shading.

An excessive level of moisture in building damages their quality. Key factors associated to the develop-ment of this damages mainly depend on the hygrother-mal fields inside building envelope. These key factors can be associated with HAM models to predict the de-velopment of moisture damages. Different granulari-ties of HAM modelling exist in literature and can be used. In this paper, main advantages and drawback of most common approaches are presented and dis-cussed. A test case is chosen to illustrate the different issues.

Simulation tools are effective for the commissioning of HVAC systems. In particular, such tools are useful not only for simulating the current state of systems but also for simulating the performance of a system provided with efficiency improvements. The Air-Conditioning System Energy Simulation for Commissioning (ACSES/Cx) tool is a software tool developed to provide specialized functions for the commissioning process.

This paper presents a methodology to measure the ef-fect of economic incentives on energy-cost optimal curves. A case-study using a net-zero energy home, located in Montréal, demonstrated the methodology. An EnergyPlus model evaluated the net-energy con-sumption objective function using 17 design variables. The life-cycle cost objective function was evaluated by post-processing energy simulation results. A multi-objective evolutionary algorithm searched the solution space for energy-cost optimal curves.

This paper explores the thermal performance of the Global Earthship design. Earthship is an autonomous earth-sheltered home utilising passive solar principles. Hourly monitoring data of the indoor temperature in such a building in Taos, New Mexico, were used to calibrate a simulation model of the building. Using the calibrated model, the performance of this design is investigated in other locations: Paris, Albacete, Seville, Valladolid, and London.

In this study the coupling of computational fluid dynamics (CFD) differential and human thermal comfort (HTC) integral numerical models is developed and used. The HTC integral numerical model evaluates the thermal comfort in non-uniform environments, while the CFD differential numerical model evaluates the airflow inside the virtual chamber and around the manikins. The numerical simulation, using upper crossed ventilation and made in winter conditions, is applied inside a virtual chamber equipped with two seated manikins, one desk and two seats.

Whole building energy models have found widespread use in estimating the energy consumption of building sys-tems. Within these models, usage profiles are assumed when capturing the influence of processes such as occu-pancy, lighting, and equipment operation. Usage profiles are defined hourly, but are repetitive in the sense that their shapes are periodic, typically, from week to week. When evaluating a design, the use of periodic usage profiles is accepted since detailed knowledge of building operation is usually unknown.