Optimal energy system sizing with independent load and weather time series

To size an energy system under uncertainty, hourly energy demand and weather data over multiple years is required. To overcome a potential data shortage, the use of time series generators is becoming a common practice. This practice disconnects the data, breaking natural correlations. The consequences on the modeling results have not been addressed and quantified. This work studies the influence of uncorrelated weather and building electric loads on optimal energy system sizing. The results show large variability in cost and technology capacity estimations for low carbon emissions levels. Correlation is however not the main cause of the observed variations.