The cost of electricity from offshore wind energy has decreased dramatically over the last decade, reaching even grid parity in favourable cases. Nevertheless, in the context of the energy transition, it is of paramount importance to continue decreasing electricity generation costs.
The CELT4Wind project winner of the WEAMEC Research call 2020 targets the the Cable Electrothermal Management for Offshore Wind Farms.
CELT4Wind is coupled with the OWARD project winner in 2016 and the ORIGAMI project winner in 2019.
Scientific advances and innovation
CELT4Wind: Cable Electrothermal Management for Offshore Wind Farms
The CELT4Wind project aims to contribute to the necessary cost reduction by targeting significant investment savings, focusing in particular on savings on the wind farm export cable. This cable benefits indeed from a very high thermal inertia, i.e. it may take several days or even months of operation at full power before it reaches its maximum allowed temperature, which is the limiting factor for energy transmission.
Hence, few transmission system operators (TSOs), who now have responsibility for the electrothermal management of this cable in more and more countries, wish now to consider the possible exploitation of this phenomenon, thus maximising power generation with an identical electrical infrastructure. Following this, in recent years, some countries have allowed offshore wind farm managers to size their wind farms at a greater power level than the one which can be transmitted through their export cable in steady state. It must be emphasized that wind farms produce at full power only a fraction of their operating time: the export cable temperature increase slowly, thanks to its thermal inertia, and may be kept below its maximum authorized temperature during the period of production at full load which is maintained only temporarily. This “undersizing” of the export cable can therefore lead to very high investment savings. However, exploiting the thermal inertia of export cables involves many scientific and technical challenges.
The optimal electrothermal management in real-time by a TSO of a cable connected to a wind farm controlled by a farm manager requires a dialogue between these two actors, the basis of which has yet to be defined in terms of the type and temporal accuracy of the exchanged information. Indeed, relevant operating conditions, which can be achieved by offshore wind farm managers, must be specified by the TSO in the framework of offshore wind farm tenders. It is this challenge that the CELT4Wind project proposes to consider. It aims to address this bottleneck from a necessarily multi-stakeholder point of view, by including an offshore wind farm developer and manager (WPD), a TSO (RTE), as well as an offshore test site manager (SEMREV). This project must also be multi-disciplinary and therefore combines researchers from electrical and thermal engineering (SATIE and IREENA).
It is based on four pillars:
- the generation of offshore wind turbine electricity production datasets (provided by RTE) based on historical wind meteorological data representative of the conditions in the English Channel/French Atlantic coast, and validated by measured data (provided by WPD)
- the development of electrothermal models of the offshore cable combining precision and computing time compatible with real-time constraints
- the development of an electrothermal management module considering uncertainties, particularly those related to electricity production forecasting
- the drafting of recommendations for technical specifications to be included in future calls for tenders for offshore wind farms
Expected technical and economic impact
The expected impacts within the framework of the CELT4Wind project are:
- a real-time model of optimal electrothermal management of export cable reusable for future projects
- a realistic dialogue protocol respecting the technical requirements and constraints of the stakeholders defined for the electrothermal management of the export cable between the transmission system operator and the manager of the offshore wind farm
Key project milestones
- September 2020 - Kick-Off of the project
- September 2022 - End of the project
Publications and papers published
- 2021-BLAVETTE A.-Upgrading wave energy test sites by including overplanting: a techno-economic analysis-Projet WEAMEC “CELT4Wind”
- 2022 – Daminov, S. Bourguet, A. Blavette, T. Soulard, D. Trichet, G. Wasselynck, H. Ben Ahmed, L. Dupont, A. Godard, P. Warlop, Optimal energy management of offshore wind farms considering the combination of overplanting and dynamic rating – Results of the CELT4Wind project – CIGRE accepted – to be published in 2022
Oral presentations with avec publication
2021-BONNARD C.-H.-Increasing the energy production of a MRE farm considering thermal and techno-economic aspects-Projet WEAMEC “CELT4Wind”
2021 – Ildar Daminov, Anne Blavette, Salvy Bourguet, Projet WEAMEC CELT4Wind, Cable Electro-Thermal Management for Offshore Wind Farms, GDR EOL-EMR, Paris, 27/11/2021