Techno-economic analysis

Techno-Economic Analysis

Techno-economic analysis of Offshore Wind Farms

The development of marine energy technology finds itself at a crossroads: a few developers have been starting full scale testing programmes but the economic feasibility of marine energy farms is not yet ascertained and, more importantly, it is not clear which scale and which concept would be feasible at different locations.

It is clear, however, that decisions should be based on economic performance so that an understanding of the economic implications that a specified configuration determines is always required, even if carried out at a very preliminary level.

There might be different objectives for a global economic assessment, depending on the stage and on the kind of evaluation: Device optimization, design of the infrastructure, components design (i.e. PTO, moorings), site selection, technology selection, or long-term global assessment (macro-economic outlook). The difference between those objectives usually depends on the stakeholders interested in the analysis.

Techno-economic models are aimed at optimizing the design and reducing the cost of offshore renewable farms, by analyzing different key aspects such as (Farm lay-out, electrical, PTO, mooring, structure components). Models are based on classical distinction between capital expenditure costs, operational costs and the estimation of the incomes of energy production.

The results of the models show NPV (Net Present Value), CAPEX and OPEX cost breakdown for a specific farm definition (Nominal power, Number of devices, Distance to shore, Distance to harbor), taking into account all the costs contributions such as: Structure, Mooring, electrical devices, PTO, Balance of plant.

O&M

The operational models focus on the cost of offshore operations, analysis and optimisation of maritime methods as an aid in decision making. Modelling site accessibility assessment with estimation of weather windows and validation against real sea operations realistically helps in the reduction of the waiting time and costs.

Models can be detailed in terms of cost breakdown of vessels, personnel, equipment and consumables required per operation as well as device availability. Each maintenance operation can be classified as corrective or preventive depending on the uncertainties in estimating component failure rates. As a main conclusion, these models identify the critical costs associated to O&M activities and help to improve OPEX strategies.

Life Cycle Assessment Studies

This type of studies is focused on the environmental impact assessment of farms, in order to identify potential areas of improvement. Life Cycle Assessment (LCA) are carried out in order to provide quantified impacts of electricity generated to compare these results with other energy generation technologies in terms of kgCO2 eq/kWh, Energy Payback Time (EPBT) and Energy Return Of Investment (EROI), followed by a sensitivity analysis.

Contact and more information: Vincenzo Nava