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International Energy Agency Energy Conservation in Buildings and Community Systems Programme www.ecbcs.org This is the last issue of the LowEx News the biannual newsletter published during the working phase of IEA ECBCS Annex 49. The main results of Annex 49 are described here together with the formats of the final products of the Annex 49. GUIDEBOOK FOR LOW EXERGY SYSTEMS The results of Annex 49 are presented in the form of a booklet, which includes the LowEx Guidebook in a CD-ROM format. It contains all the material produced within the project: newsletters, publications, the exergy analysis tools and the full version of the guidebook (also as a printable .pdf version). In addition, the same information can be found in the Annex 49 webpage: www.annex49.com. Main objectives and layout of the final report In this context, the main objectives Annex 49 were: 6.1.5. Air tightness 6.1.6. Low-exergy ventilation 6.1.7. Effective fans and pumps 6.1.8. Conversion of fuels to heat and electricity 6.1.9. Heat pump 6.1.10. Daylighting 6.1.11. Conversion of solar energy to heat 6.1.12. Conversion of solar energy to electricity 6.1.13. Control-demand based-IT 6.1.14. Thermal inertia-thermal storage 6.1.15. Ground coils 6.1.16. PCM storage 6.1.17. Cooling beams 6.1.18. Thermally activated hollow core decks (TermoDeck) 6.1.19. Air heating and cooling 6.1.20 Economy and cost effective solutions for low exergy buildings 6.2. Innovative building case studies 6.2.2 Innovative Concepts for Exergy Efficient Airconditioning Systems and Appliances in Buildings 6.2.3. Temperature and humidity independent control (THIC) airconditioning system 6.2.4. Adjustment of the ventilation rates based on the variation in time of the actual needs 6.2.5. Seasonal heat storage with ground source heat pump system 6.2.6. Shallow ground heat storage with surface insulation 6.2.7. Exergy recovery from wastewater in small scale integrated systems 6.3. Conclusions 6.4. References Tool

Exergy analysis is a more powerful tool than mere energy analysis for showing the improvement potential of energy systems. Direct use of solar radiation instead of degrading other high quality energy resources found in nature is advantageous. Yet, due to physical inconsistencies present in the exergy analysis framework for assessing direct-solar systems commonly found in literature, high exergy losses arise in the conversion process of solar radiation in direct-solar systems. However, these losses are disregarded in indirect-solar systems. In this paper, contradictions and physical inconsistencies which result from including the conversion of solar radiation only for direct-solar systems are shown. An evaluation framework physically coherent for systems making direct and indirect use of solar radiation is derived and its physical correctness is thoroughly discussed. Results from case studies using the proposed framework are presented and compared with the conventional approach, enabling their direct comparison and better understanding of the benefits and correctness of the proposed method. The new method allows recognizing clearly the suitability of direct-solar systems, being appropriate for highlighting more sustainable energy supply systems. Although this paper focuses on building systems, the framework might be used for exergy analysis of direct-solar systems in the context of other energy uses

The role of faculty in higher education as knowledge disseminators within the knowledge and digital society can be completely redefined. This paper presents results from a video-based flipped classroom approach combined with a project-oriented learning arrangement. I show that videos combined with a project-based learning setting can be a powerful tool to facilitate the shift from knowledge dissemination to knowledge appropriation. Besides, results show a high level of student's satisfaction and achievement during the course. The competences obtained by the students during the course reach far beyond those possible in a similar course with a traditional teaching approach.