OPTIMIZING THE BUILDING ENVELOPE AND HVAC SYSTEM FOR AN INPATIENT ROOM USING SIMULATION AND OPTIMIZATION TOOLS Vojislav Novakovic 1 , Johnny Normann Holst 2 , Milos Kostic 3 Keywords: Thermal comfort, Simulation, Optimization Abstract Integrated design is recognized to be a very promising procedure to obtain sustainability throughout the lifetime of a building. The fundamental preconditions for successful integrated design are: a collaborative design team, a flexible computer model, and a systematic approach to evaluating design strategies. The simulation and optimization tools are crucial elements of this process. Even though simulation is being increasingly used in design of modern buildings, the full potential of simulation is usually not achieved. To improve building and HVAC system performance, designers usually guess different values of building and system parameters based on their own experience. Then they redo the simulation without knowing if the guessed values will lead to improvement. This approach to evaluate design strategies is inefficient and labor intensive. In addition, if the number of parameters being varied exceeds two or three, the designer can be overwhelmed in trying to understand the nonlinear interactions of the parameters. However, techniques exist that allow automatic, multidimensional optimization of a simulation model, leading to better design with less effort. In this paper, we will describe how such optimization can be done using the simulation program Energy Plus and the generic optimization program Gen Opt. We will show an example of how to use these two programs to design an inpatient room at the St. Olavs Hospital in Trondheim, Norway. The optimization goal is highest possible thermal comfort achieved for the bed-ridden inpatient besides the minimal source energy consumption for heating, cooling, and lighting with respect to the selected design parameters. Two different methods for predicting of the thermal comfort sensation will be elaborated and compared. 1 Norwegian University of Science and Technology, N-7491, Trondheim, Norway, Vojislav.Novakovic@ntnu.no 2 Norwegian University of Science and Technology, N-7491, Trondheim, Norway ,johnny.n.holst@ntnu.no 3 Mechanical engineering faculty of Belgrade University, 11000 Belgrade, SCG, kocta@eunet.yu The 2005 World Sustainable Building Conference, Tokyo, 27-29 September 2005 (SB05Tokyo) - 478 - 01-069