Performance Analysis of Solar Combi-system in a Swedish Demonstration House

Abstract: Global energy demand is increasing every year dramatically, which results global warming due to increased greenhouse gas emissions. So, to be environmentally friendly and sustainable, Sweden’s energy policy targets to reach 100 % renewable energy share in 2040. Already, Sweden achieved 50 % renewable energy share in 2012 which was targeted to achieve by 2020. Integration of solar heating system in residential sector, for space heating (SH) and domestic hot water (DHW), was one of the reasons for this achievement. Considerably, several numbers of solar heating systems were installed in houses until 2011. Thus, solar heating system could be a step towards to reach 2040s target. In 2011, detached Swedish house was installed with solar combi-system (SCS) which was designed to use 53% of solar energy. The main aim of this thesis is to analyze the thermal performance of SCS and correlation with its simulated system performance which is done in five steps.First step is the collection of measured data from the system for specific period one year from April 2019 to March 2020 and determined other unknown energy values in that data. In the second step, unknown data are calculated using scientific equations with information from users and reliable assumptions. Consequently, the analysis of measured data shows huge uncertainties. It follows to the third step as sensitivity analysis to enhance the assumption values. Thus, analyzed results are tabulated with reliable parameters and solar fraction (SF) of the measured data is calculated. In the fourth step, SH of the house is considered as reference to build a system model in Polysun simulation software, and the modelled results are verified with analyzed results. In the final step, system model is simulated by changing one-year weather profile to 10 years average weather profile. Thus, analyzed results and simulated results are compared to evaluate the performance. The real system has the SF of 52 % after sensitivity analysis whereas the simulated system showed the SF with percentage difference around 15 %.