Kondili E., Kaldellis J.K., 2004, "Incorporating of Sustainability Considerations into the Industrial Operational Planning Systems", ESCAPE 14 International Conference, 16-19 May 2004, Lisbon, Portugal
Chalvatzis K.J., Spyropoulos G.C., Kaldellis J.K., 2004, "The Contribution of the Greek Electricity Generation Sector on the Global Climate Changes", International Conference of Protection and Restoration of the Environment VII, July 2004, Myconos, Greece
Kaldellis J.K., Spyropoulos G., Chalvatzis K.J., Vlachos G., 2004, "Estimating the Energy Related Nitrogen Oxides Production in Greece, for the Next Decade", 7th Hellenic Conference in Meteorology, Climatology and Atmospheric Physics, Univ. of Cyprus, 27-29 September, Nicosia, Cyprus.
Kaldellis J.K., Chalvatzis K.J., Spyropoulos G., Paliatsos A., 2004, "Transboundary Air Pollution in Greece. Economic and Political Aspects", 7th Hellenic Conference in Meteorology, Climatology and Atmospheric Physics, Univ. of Cyprus, 27-29 September, Nicosia, Cyprus.
Kaldellis J.K., Kavadias K.A., Korbakis G., Vlachou D.S., 2004, "The Impact of Local Ambient Conditions on the Energy Production of Contemporary Wind Power Stations", 7th Hellenic Conference in Meteorology, Climatology and Atmospheric Physics, Univ. of Cyprus, 27-29 September, Nicosia, Cyprus.
Καλδέλλης Ι.Κ., Κονδύλη Αιμ., Κορμπάκης Γ., 2004, "Διαχείριση Υδάτινων Πόρων στα Νησιά του Αιγαίου: Αξιολόγηση Εναλλακτικών Λύσεων", 7ο Πανελλήνιο Γεωγραφικό Συνέδριο, Μυτιλήνη, Οκτώβριος 2004.
Καλδέλλης Ι.Κ., Καββαδίας Κ., Παλιατσός Αθ, 2004, "Προβλήματα Χωροθέτησης Εγκαταστάσεων Ηλεκτροπαραγωγής: Η Περίπτωση των Αιολικών Πάρκων", 7ο Πανελλήνιο Γεωγραφικό Συνέδριο, Μυτιλήνη, Οκτώβριος 2004.
