Applying uncertainty considerations to building energy conservation equations

When applying simulation tools in practice uncertainties abound, for example in material properties, casual heat gains and infiltration rates. To facilitate the quantification of the effects of uncertainties, the differential, factorial and Monte Carlo methods have been implemented within ESP-r. An alternative approach is to embed uncertainty considerations within a simulation tool's algorithms. The principle advantages of this method are that the uncertainty is quantified at all times and therefore requires only a single simulation. Coupled with this, it is possible to take control action based on the prevailing effects of uncertainties. This paper details the mathematical techniques required to integrate uncertainty considerations within the full set of building energy conservation equations. A comparison is made between the use of this novel approach and traditional mechanisms of assessing uncertainty. Finally, the advantages and disadvantages of the new approach are discussed.