English

Optimizing the operations of a HVAC system in response to the dynamic loads and varying weather conditions throughout a year can result in substantial energy savings.  However, the problems related to HVAC system optimization are always discrete, non-linear and highly constrained. So, a simulation-based optimization approach for a HVAC system is proposed.

The present work reports an experimental procedure designed to verify a particular solution for the distri-bution of artificial light sources. The inverse method to illumination by optimization technique, IMIbyOP-TIM, is applied to generate an uniform field of illumi-nation as a result of the free location of purely diffuse light sources. A reduced scale enclosure is build to measure the effectiveness of the method on indoor en-vironments. The illumination field is observed over a work plane placed parallel to the floor and measured by photovoltaic sensors.

Heating and cooling load estimation is based on the heat balance method. Although this method has strong physical basis, it yields an acausal system when the heat capacity of the indoor space is non-negligible. New emergent problems in low energy buildings require time steps significantly smaller than 1 hour, which is usually used by simulation software. Therefore, when the time step tends to zero, the calculated load tends to infinity when the indoor air temperature has an incremental variation.

This paper deals with the global model based antic-ipative energy management system adapted for the CANOPEA building prototype proposed by the team Rhˆone-Alpes for the Solar Decathlon Europe con-test. It presents a practical application of theoreti-cal studies originally developed in Grenoble Research labs (G-SCOP, G2Elab and LIG) and improved by the Vesta-System company.

The objective of this paper is to present a general methodology for the calculation of thermal response factors, known as g-functions, of vertical borehole fields. The methodology accounts for the time variation of the heat extraction rates of individual boreholes. In addition, the original concept of the g-functions is extended to include variable borehole lengths and buried depths. Finally, the methodology is implemented into MATLAB with a convenient graphical user interface which pre-processes the hourly values of the thermal response factors for use in energy simulation programs.  

Retrofitting our current building stock is a vital part of meeting emissions reductions targets, using energy in a more efficient way and creating sustainable lifestyles. However, one of the key barriers identified is a lack of tools to support making retrofitting decisions. In this paper, the creation of a transparent and flexible building energy performance simulation model - SdSAP is reported to assist building owners and investors to make better informed decisions in building retrofitting activities. A case study is provided to demonstrate the benefits of using the SdSAP tool.