Energy efficiency vs subjective comfort: a multiobjective optimisation method under uncertainty

A multiobjective optimisation methodology is proposed to optimise building design against both physical performance (such as energy efficiency) and psychophysical performance (such as occupant comfort). The originality of the method is 1) the integration of subjective data obtained from psychophysical tests in multiobjective optimisation method and 2) the management of uncertainties inherent to subjective data through a Monte Carlo process. The methodology was developed through a case study of office lighting optimisation.

Feed-forward air-conditioning control using a weather forecasting data in school building in heating season

To achieve the low-carbon society, Japanese government has conducted; 1) to revise “Laws Concerning the Rational Use of Energy”, 2) to manifest reducing 25 % of CO2 emission, and 3) to participate COP15 as international activity. Various techniques have been applied for energy conservation of building individually.

Energy saving by cooperative operation between district heating and cooling plant and building HVAC system

District heating and cooling (DHC) systems show a great potential for energy saving. However, a number of problems related to heating, ventilation, and air conditioning (HVAC) systems within a building resulted in an increase in energy consumption. The main reason is that the DHC plant and the building air conditioning systems are operated separately. This study proposes a new energy service in which the operator of the DHC plant controls air conditioning systems in the buildings simultaneously.

Numerical study on the carbon dioxide distribution in a naturally ventilated space

Carbon dioxide concentration is often taken as an indicator of indoor air quality, especially in spaces where human beings are the main contaminant source. Therefore this CFD analysis focuses on the CO2 dis-tribution in a sports hall, representing large and high enclosures. A buoyancy driven natural ventilation sys-tem prevails in the absence of wind, so that a pol-lutant stratification can be expected corresponding to displacement ventilation.

From technical to usage energy efficiency in buildings: application to a heated room

 In the context of more and more efficient building research, as passive house or Energy plus building, the occupants have become a central actor of building system. In order to integrate them in the design phase of a building, it is proposed to complete the classical definition of “energy efficiency” with the concept of “usage energy efficiency”. This concept integrates the notion of satisfaction and energy consumption which are summarized in a compromise decision plane.

Development of the automatic optimization and degradation detection tool for hvac primary system

Automatic optimization and degradation detection tool for HVAC primary system was developed. It synchronizes with Building Energy Management System (BEMS), and it does optimization and degradation diagnosis automatically. Generally, the tools based on the simulation are low generality because of the complex input. Therefore, the targeted system of this tool is limited to the primary system that is specific standard configuration to reduce the input data. The optimization function outputs the best set point according to the outside temperature and the load etc.

Energy use of buildings at urban scale: a case study of london school buildings

The diversity of non-domestic buildings at urban scale poses a number of difficulties to develop building stock models. This research proposes an engineering-based bottom-up stock model in a probabilistic manner to address these issues. School buildings are used for illustrating the application of this probabilistic method. Two sampling-based global sensitivity methods are used to identify key factors affecting building energy performance.

Spatial distribution of pressure drag acting on rectangular block arrays with various layouts

This study reported a series of wind tunnel experiments on the spatial distribution of the pressure drag acting on the walls of rectangular block arrays, which were arranged in staggered, square, and diamond layouts under the conditions of different packing densities. The obtained bulk pressure coefficients of a block located in various staggered arrays showed clear dependency of packing density.

An approach for a statistical model for the user behaviour regarding window ventilation in residential buildings

In this paper a user model for the use of windows based on measurements in residential buildings is developed. Detailed literature review provides an overview of existing user models. Most of them base on measurements in office buildings and their validity for residential buildings is questionable. All models are based on different kinds of statistical methods.  After detailed assessment of these methods and the analysis of their applicability to the measurements, a new methodological approach is applied, to take the auto-correlation in the longitudinal data into account.

Effect of envelope properties and thermal adaptation on energy consumption and comfort conditions through simulation of various ECMs

The study, conducted in composite climate of India, exhibits improvement in energy efficiency of a conditioned building block with the use of energy conservation measures (ECMs) recommended by National Energy Conservation Building Code (ECBC). In first part of it, subject building model was individually applied with five ECMs and two combinations of these ECMs by using constant thermostat settings. Similarly in second part of the study the same was done with adaptive thermostat settings.

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