atmospheric emissions and the structure of electricity generation some empirical evidence from portuguese case mónica alexandra meireles1 maria isabel soares2 january 2006 1 department economics iscte av forças armadas 1649 026 lisboa portugal e mail monica meireles pt 2 faculty university oporto r roberto frias 4200 464 porto isoares fep up abstract as a small open economy has faced substantial changes in last 15 years however its supply remains extremely dependent on hydroelectric production which turn is strongly linked to hydrological fluctuations then power system main derive combustion plants used dry fulfil demand this paper intends illustrate recent evolution sector eu 25 context together with impact it also aims evaluate major fossil fuel environment analyse correlation between market liberalisation restructuring energy related activities are sources greenhouse gases ghg relative importance total co2