The cornerstone of the work of the Sustainable Urban Development research group at the LESO / EPFL is the development of LESO-SUNtool. A successor to the EC project SUNtool, this software is conceived to simulate energy, water and waste flows at the scale of the urban district and beyond. The purpose of this software is to support urban planning and policy decision makers to optimise the sustainability of new and existing urban settlements. For this the core modelling capability includes a thermal model, HVAC models, energy conversion system models, an integrated radiation model and a family of stochastic behavioural models. The key aim of the work described in this seminar is to develop techniques to support the optimisation of the modelled urban resource flows. Given the vast number of variable permutations involved, it is highly unlikely that a user would be able to find an optimal solution by trial and error. Instead, we proposed efficient computational techniques that are adapted to the non-linearity of the models and the non-continuity of the input data. For this a hybrid of two methods ”Covariance Matrix Adaptation Evolution Strategy” and ”Hybrid Differential Evolution” is proposed. This new evolutionary algorithm has been initially tested against standard benchmark functions and in conjunction with the ray tracing software Radiance to optimize urban geometric forms for the utilization of solar irradiation. The next and final stage in this work is to apply the algorithm to optimise the set of modelled resource flows for the district of Matthaeus (in the city of Basle, Switzerland) using LESO-SUNtool.