*3.3. Uncertainties and Improvement Possibilities*

It is important to be aware that there are uncertainties in all the data handled throughout the calculations. Therefore, there will be uncertainties in the output results.

A quantification of the uncertainties that accompanied the cost assessment of wave energy technologies was proposed in [55]. The quantification depends on the technology's development stage (TRL) and the type of assessment (preliminary, baseline, detailed, etc.) that is carried out. This quantification has been used in [4,29,51], among others, and has allowed us to provide a sensitive evaluation of uncertainties. Table 8 summarises the uncertainties associated to a preliminary cost evaluation.


**Table 8.** The uncertainty of the LCoE estimates as a function of the development stage [55]. Data adapted from [55].

Accordingly, the associated uncertainty to the estimated values at the present development stage of the LiftWEC concept (at TRL 2) is about (−30/%, 50)%. This is an important fact to take into account, as it reflects that there are also lot of uncertainties on the technological side. The end-of-project target LCoE of 120 EUR/MWh (expected at TRL 4) has an associated uncertainty of (−25, 30). This reduction in uncertainty is associated to the advancements of technology development. The first results form tank testing, and refined numerical modeling will be available. Furthermore, annual energy production estimates will include the contribution of a specific-designed control strategy. The inclusion of such a control strategy will also affect the OPEX (to a large extent) and CAPEX, which will be evaluated and examined in detail. At this stage, a more specific description of costs will be drawn.
