IBPSA2009

Solar shading can be used to decrease the cooling power demand and cooling energy use but that also reduces the possible benefit for heating with the incoming solar radiation when there is a heating need. The apparent solution is to shade when there is a cooling need and allow solar gains when there is a heating need. This paper presents energy use simulations on such a system set up in a theoretical office cell and a theoretical apartment in southern Sweden showing remarkable decrease in energy use for heating and cooling, or too high over indoor temperatures.

In non-residential buildings, comfort and energy demand for heating, cooling and lighting are significantly influenced by the façade.  Up to now, only non-weighted luminance-based methods for calculating and evaluating annual daylight glare exist (Lee et al., 2005; Mardaljevic and Lomas., 1998). Within this paper, different methods based on the daylight glare probability DGP (Wienold and Christoffersen, 2006) for a dynamic calculation of glare are discussed and evaluated: 

1. Timestep by timestep calculation –RADIANCE reference method.

This paper proposes an interactive goal-based method for designing daylit buildings.  The lighting simulation tool which supports this process is a hybrid global illumination rendering method which efficiently computes annual daylighting metrics.  The goal-based method uses a knowledge base populated using a set of previously completed simulations that quantify the effects of various façade design modifications.  The knowledge base guides a simple algorithm over an iterative design process.

This paper provides an overview of a new method for modelling the total solar energy transmittance. It is implemented in the ESP-r building simulation program to model complex façades such as double glazed façades with external, internal or integrated shading devices. This new model has been validated and tested for several cases.

Fenestration and its design have a significant impact on the energy use associated with the artificial lighting, heating and cooling of a building. To date, research into window optimization has been for windows that are constrained to have a regular geometric shape and position. This paper describes an approach in which a building façade is divided into a number of cells, each cell having one of two possible states, a solid wall construction, or a window.

The objective of this work is to evaluate the quality of the predictions of the indoor airflow behaviour by the zonal method in comparison to the CFD results. The isothermal airflow of the International Energy Agency Annex 20 test cell was chosen to perform the proposed comparative analysis. This cell represents a rectangular room where the air is supplied horizontally on the upper left and is exhausted through an opening located on the lower right on the opposite side.

We introduce a framework and proof of concept for estimating building energy consumption that probabilistically combines a model of building physics with observed occupancy and detailed operations data, automatically learning a physically plausible model of the energy consumption. Our framework has several desirable properties: data about one building can automatically be used to improve energy use estimates for other similar buildings; input fields can be left blank or specified approximately; and the output of our model is not only an estimate of energy usage, but a probability distributi

This paper compares the energy performance of three office buildings as predicted by building simulation (using only the information typically available at the design stage) with the measured energy consumption of the same buildings in operation for a twelve-month period. The buildings are located in Canberra, Australia.

Damage to human health as a result of exposure to contaminants emitted to indoor air is poorly addressed in life cycle assessment tools for dwellings. A new model is available to calculate damages to human health caused by contaminants emitted from building materials, using a multizone indoor airflow and exposure model. Ventilation rates and radon concentrations have been simulated for the Dutch reference dwelling and are compared with measurement data from the Dutch Ecobuild houses and from average ventilation rates and radon concentrations in dwellings in the Netherlands.

Although simulation has traditionally been cast as a comparative tool, there is an increasing drive for  simulation to provide information on absolute performance. In this paper, key requirements are outlined for the credible prediction of absolute performance, including reporting, energy coverage, separation of behavioural and technical influences, modelling HVAC control, risk analysis and the use of simulation to generate energy targets for operation and commissioning. It is identified that the best outcomes are likely to be achieved if changes are made to design process and the role of t