In the discussion on practice-oriented measures to reduce the CO2 emission, one measure most demanded is the development of zero heating energy houses. The technology applied and investigated in the first pilot projects seems to indicate a possible future without any CO2 emission with respect to residential building. What is really hidden behind this technology and whether it is feasible to introduce it into construction practice, is to be discussed in this contribution with regard to practical experiences.

Pilot houses with solar air heating systems were and are being erected in Hungary by the ''THERMO Ltd." Company. This project had two goals: to adapt the OM concept as a whole, including the thermal properties of the building itself, and to check the performance of the elements of the OM system applied on houses, built according to the local standards and practice. The experiences of a building, built according to the local standards and practice are briefly presented in the paper.

The OM solar system is one of various passive systems. As is in the general passive system, the technique in the OM solar system works with the designing and architectural space as a unity. In other words, the technique is a part of the designing. Nowadays a lot of new technique have been developed and all kinds of related technology are born. During the past nine years, the system has been already employed in about eight thousand homes and sixty public buildings all over Japan.

The paper is the second in a series of four which describe a three-year research project into advanced fabric-energy-storage (FES) systems. It presents the construction and validation of a computational-fluid-dynamics ( CFD) model of the 'FES-slab' which is subsequently used to investigate the slab's behaviour under a variety of boundary conditions and with modified air paths. Similar models are used to compare the FES-slab with the competing 'generic slab' and 'hollow-core screed' advanced FES systems.