Solar power: An approach to transformity evaluation

The current challenge concerning renewable energy sources resides in making them efficient and competitive in comparison with traditional ones without neglecting the appraisal of environmental performances. In particular, envisaging a sustainability perspective, this task must be accomplished from a wider, and then holistic, viewpoint. For this purpose, authors identified emergy analysis as a valid approach. Actually, during the implementation of a previous work, authors found incomplete (for the attainment of their aims) the information concerning emergy evaluation of energy production by sunlight. This study represents an attempt to fill this gap, aiming at supplying a starting basis to evaluate these technologies. Emergy parameters were then calculated for two suggested plants (a thermal and a photovoltaic one) and results were compared with traditional energy production systems. This comparison revealed that solar technologies imply a remarkable emergy saving (5.72E+15 sej/year for thermal and 4.77E+15 sej/year for photovoltaic). These evaluations make solar power technologies advisable in order to save non-renewable resources. Moreover, the analysis demonstrated recent and remarkable improvements in photovoltaic electricity production efficiency. This condition sets a positive scenario considering the expected and outstanding further improvements in solar technologies.