The cost of the energy extracted by ocean surface waves depends on many technological-physical factors like conversion principle, wave energy potential, water depth, shore distance, and ocean floor characteristics. Economic factors, like assumed discount rate, cost reduction due to technological improvement and fiscal incentives, are extremely important too. The Mediterranean Sea and the Tyrrhenian Sea in particular, possess an interesting energy potential. At some locations offshore Sardinia and Sicily the wave energy density is of the order of 10kW/m. In this paper the energy production has been computed for three different wave energy converters (AquaBuOY AWS and Pelamis), at two promising locations in the western Italian seas.. The energy cost has also been computed for the Pelamis device at Alghero site which has the highest wave energy potential. The results indicate that the existing Pelamis converter is oversized with respect to the typical wavelength of the investigated sites After proper scaling of the device, the performance in the energy conversion could become economically attractive also for Italian seas.