Since accurate simulation models are important tools for solar system designers, IEA SHC researchers devoted most of their efforts to the assessment and improvement of computer models used to predict the performance of active solar heating systems. First, the results obtained by each country's computer code when predicting the performance of two hypothetical systems were compared. This was followed by validation studies which compared the results of model predictions to measured data from actual solar systems.

Other Task 1 activities included a review of different methods employed for designing optimized systems and the development of a uniform system performance reporting format to facilitate information exchange.

Some work was also undertaken on solar assisted low energy dwellings; however, that work was soon transferred to a new task on passive systems (Task 8).


  • Model Comparison and validation
  • Performance measurement procedures
  • Reporting format for system performance
  • Optimization procedures
  • Solar-assisted low energy dwellings