The energy consumption demands are in future set mainly on total (primary) energy consumption. Therefore, this must be able to be calculated reliably. Dynamic simulation models of buildings offer a seemingly reliable calculation method. The principles of these programs are, however, very different, and the input data of the programs is different. Therefore, the calculation results of the simulation programs are far not unambiguous. The most unambiguous results of calculations can be achieved when the calculation method is reliable enough and when sufficiently reliable and adequate input data is available. EN and ISO standards, from which the key is EN ISO 13790, provide a reliable and verified ground for the calculation of energy consumption of buildings and their technical systems. Therefore, the implementation of these international standards into Finland and their further development is an important research area.
The European standardisation organisation (CEN) has published the energy package, which includes 43 key standards for the energy performance of buildings, building physics and ventilation and heating systems. This provides a good basis in the future for a reliable calculation of energy consumption of buildings.