Building shape optimisation to reduce air-conditioning needs using constrained evolutionary algorithms

The purpose of this paper is to analyse the optimal three-dimensional form of buildings that minimise energy consumption due to solar irradiation. We use an evolutionary algorithm (hybrid CMA-ES/HDE algorithm) already applied to maximise solar energy utilisation (Kampf and Robinson, 2010), which uses a cumulative sky model approach for the computation of incident irradiation on the building envelope. Various families of possible building forms are investigated with this methodology to find the optimal building form, in two locations with radically different climatic conditions, showing the features that a building should posses in order to optimise its energy performance with respect to the solar irradiation. (C) 2015 Elsevier Ltd. All rights reserved.

Air-Conditioning Energy Production through a Building Shape Optimization

Gianpiero Caruso, Jérôme Henri Kämpf

The air-conditioning energy consumption, for cooling or heating, has currently a growing trend. The purpose of this work is to develop a method suitable to design optimal threedimensional building forms to reduce air-conditioning needs in a chosen location by using weather data. The method exploits in particular both diuse and direct solar radiation; not independently but rather in relation with the external temperature. For this reason this method could be applied in any climatic region. In fact the warmer the region is the more negative the contribution of the solar radiation is in terms of building energy balance. Hence in this case the problem tends to be equivalent to the one of the annual solar irradiation minimization. On the contrary, in the case of cold regions, the problem tends to be equivalent to the one of the annual solar irradiation maximization. The final aim is to guide designers to reduce energy consumptions in buildings, since the first stages of the design process of future buildings. To achieve that aim, an algebraic cumulative sky is introduced for the computation of the annual useful incident solar irradiation on the building envelope. The methodology consists in using weather data to define in which case the solar irradiation on the envelope gives a positive or negative contribution depending on the external temperature in order to maintain internal comfort of the occupants. The contribution is further associated to the data of the solar irradiation for each hour of a typical year. The algebraic cumulative sky constructed on that basis has the advantage to present particular zones where the solar radiation is useful all year long. Finally we use an hybrid evolutionary algorithm (CMA-ES/HDE algorithm) already applied to maximize solar energy utilization to explore the optimal building forms maximizing the annual useful solar irradiation on the envelope.

EPFL Solar Energy and Building Physics Laboratory (LESO-PB)2013

Optimisation of buildings solar irradiation availability

Raffaele Bolliger, Josep Bunyesc Palacín, Jérôme Henri Kämpf, Marylène Montavon, Darren Robinson

In order to improve the sustainability of new and existing urban settlements it is desirable to maximise the utilisation of the solar energy incident on the building envelope, whether by passive or active means. To this end we have coupled a multi-objective optimisation algorithm with the backwards ray tracing program RADIANCE which itself uses a cumulative sky model for the computation of incident irradiation (W h/m2) in a single simulation. The parameters to optimise are geometric (the height of buildings up to their facade and the height and orientation of roofs), but with the constraint of maintaining an overall built volume, and the objective function is heating season solar irradiation offset by envelope heat losses. This methodology has been applied to a range of urban typologies and produces readily interpretable results. The focus of this work is on the design of new urban forms but the method could equally be applied to examine the relative efficiency of existing urban settlements, by comparison of existing forms with the calculated optima derived from relevant specifications of the building envelope.

2009

Air-Conditioning Energy Production through a Building Shape Optimization

Gianpiero Caruso, Jérôme Henri Kämpf

EPFL Solar Energy and Building Physics Laboratory (LESO-PB)2013