01796nas a2200217   4500008003900000245010600039210006900145260001200214300001200226490000800238520106600246653002801312653001301340653002901353653002001382653001501402100002001417700001901437700003101456856009101487       2015                          d00aEquation-based languages – A new paradigm for building energy modeling, simulation and optimization0 aEquationbased languages A new paradigm for building energy model  c04/2016  a290-3000 v1173 a<p>Most of the state-of-the-art building simulation programs implement models in imperative programming languages. This complicates modeling and excludes the use of certain efficient methods for simulation and optimization. In contrast, equation-based modeling languages declare relations among variables, thereby allowing the use of computer algebra to enable much simpler schematic modeling and to generate efficient code for simulation and optimization.</p><p>We contrast the two approaches in this paper. We explain how such manipulations support new use cases. In the first of two examples, we couple models of the electrical grid, multiple buildings, HVAC systems and controllers to test a controller that adjusts building room temperatures and PV inverter reactive power to maintain power quality. In the second example, we contrast the computing time for solving an optimal control problem for a room-level model predictive controller with and without symbolic manipulations. Exploiting the equation-based language led to 2200 times faster solution.</p>10aEquation-based modeling10amodelica10aMulti-physics simulation10aOptimal control10asmart grid1 aWetter, Michael1 aBonvini, Marco1 aNouidui, Thierry, Stephane  uhttps://simulationresearch.lbl.gov/publications/equation-based-languages-%E2%80%93-new