Methodology to calculate the costs of a floating offshore renewable energy farm

Abstract

This paper establishes a general methodology to calculate the life-cycle cost of floatingoffshore renewable energy devices, applying it to wave energy and wind energy devices. It isaccounts for the contributions of the six main phases of their life-cycle: concept definition, designand development, manufacturing, installation, exploitation and dismantling, the costs of which havebeen defined. Moreover, the energy produced is also taken into account to calculate the LevelizedCost of Energy of a floating offshore renewable energy farm. The methodology proposed has beenapplied to two renewable energy devices: a floating offshore wave energy device and a floatingoffshore wind energy device. Two locations have been considered: Aguçadoura and São Pedro deMoel, both in Portugal. Results indicate that the most important cost in terms of the life-cycle ofa floating offshore renewable energy farm is the exploitation cost, followed by the manufacturingand the installation cost. In addition, the best area in terms of costs is the same independentlyof the type of floating offshore renewable energy considered: Aguçadoura. However, the resultsin terms of Levelized Cost of Energy are different: Aguçadoura is better when considering waveenergy technology and the São Pedro de Moel region is the best option when considering floatingwind energy technology. The method proposed aims to give a direct approach to calculate the mainlife-cycle cost of a floating offshore renewable energy farm. It helps to assess its feasibility andevaluating the relevant characteristics that influence it the most.