THIS PROJECT RESPONDS TO FOUR MAIN NEEDS EMERGING FROM A THOROUGH ANALYSIS OF THE SPECIFIC LITERATURE:-INDIVIDUATION OF A STANDARDISED ACCOUNTING METHOD FOR ENVIRONMENTAL COST, RESOURCE ALLOCATION AND THE OVERALL IMPACT OF AN ENERGY SYSTEM. VARIOUS METHODS HAVE BEEN PROPOSED, BUT CONSENSUS ON THE MOST APPROPRIATE RESOURCE COST ACCOUNTING SCHEME IS STILL NON-EXISTENT,-CARATING OF ENERGY RESOURCES. THE EXERGIA Ê IS IDENTIFIED AS A COMPLETE THERMODYNAMIC METRIC FOR THE QUANTIFICATION OF BOTH PRIMARY RESOURCES AND END-USES,-VALUTATION OF THE EFFICIENCY OF ENERGY SYSTEMS FROM A LIFE CYCLE PERSPECTIVE (CONSTRUCTION, OPERATION AND DISPOSAL, INCLUDING SITE RECYCLING AND RESTORATION). MOST OF THE PERFORMANCE INDICATORS CURRENTLY AVAILABLE FOR ENERGY CONVERSION SYSTEMS USING TRADITIONAL FIRST AND SECOND LAW INDICATORS NEGLECT INDIRECT EFFECTS.