Abstract
This paper presents a short overview of the development of wave energy converters (WECs) since the 1970s where the oil crises raised the interest in renewable power generation. The “small is beautiful” motto is dealt with and dismissed when regarding the commercial viability of utility scale WEC power plants. The potential future developmental pathway towards commercialisation of wave energy is compared to the development of the Danish wind mill sector where the first series production of 22 kW started in 1978 – four years after Prof. Stephen Salter presented his MW sized so called Duck. The paper discusses the capital expenditure CAPEX and operation and maintenance costs (OPEX) for small and large WECs seen over the WEC lifetime and the resulting levelized cost of energy (LCOE) for power plant size wave energy parks. The following statement is taken from the 2014 JRC Ocean Energy Status Report [8]: “Maintenance: small-scale devices are associated with reduced maintenance, since they are designed to operate in farms and a defect to one unit may not affect the overall array performance, hence reducing the time necessary for maintenance.” The paper explains why this is a false statement - maintenance costs will inevitably decrease with increasing WEC size. The paper also justifies that large WECs can obtain relatively low CAPEX and OPEX compared to small WECs, and that large WECs can be expected to match the LCOE for floating wind turbines. Combined offshore wave-wind power plants can be expected to deliver lower LCOE than pure wave or wind parks.