  The offshore oil and natural gas platforms, mostly powered by diesel or gas
generators, consume approximately 16TWh of electricity worldwide per year,
which emits large amount of CO2. To limit their contribution to climate change,
a proposed solution is to replace the traditional fossil fuel based energy
resources with offshore clean energy. One of the main challenges in designing
such a system is to ensure that energy demand is met while minimizing cost and
reducing environmental impact. To address this challenge, several strategies
including microgrid systems consisting of offshore wind turbines, wave energy
converters, tidal energy converters, floating photovoltaic systems and battery
energy storage systems are being proposed. In this paper, cost optimization for
sizing these renewable energy sources is investigated. A cost optimization
renewable sizing (CORS) model is proposed to optimize the sizes of the
generation and storage resources. The proposed CORS model considers the
variability of the power outputs of various renewable energy sources and load,
as well as the cost of different generation technologies and the energy storage
system. Simulations conducted on three test systems show the proposed resource
sizing method significantly reduces the total lifetime cost of energy while
maintaining a high level of reliability and sustainability.
