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ELISA Report Summary

Project ID: 674741


Reporting period: 2015-06-01 to 2016-05-31

Summary of the context and overall objectives of the project

The offshore wind market is a young and rapidly growing market facing technological challenges, as it is set to move into deeper waters further offshore while being able to reduce the costs in order to reach a competitive LCOE (levelised cost of energy). For water depths above 40m (70% of the future market) approximately 40-50% of investment corresponds to the substructure (foundation and tower). Therefore, a significant cost reduction in foundation/tower would drastically improve the overall cost of offshore wind energy.
ELISA project responds to these challenges through the development and construction of the full scale prototype of a revolutionary substructure system for offshore wind turbines to be installed in the Canary Islands. The project brings to completion a 5-year development, which will be pioneer in enabling the craneless and vessel-free installation of complete onshore-assembled wind turbines, a radical step forward for cost-effective and industrially deployable deep offshore wind.
The technology, developed and patented by Esteyco, is based on the use of a self-transporting GBS and a self-lifting precast concrete tower, suitable for depths in the 20-55m range. The main advantage of this technology is that it does not require the very large, scarce and expensive auxiliary means for transport or erection that are needed for alternative solutions, originating significant savings and increasing the scalability of the solution.
The ELISA project covers the design, manufacturing and installation of the GBS in deep waters. The manufacturing will take place at the Arinaga Harbour, where the dry-dock has been built in order to provide the adequate space and conditions for the foundation to be manufactured. Afterwards, the foundation and the bottom part of the shaft will be loaded out in order to install the auxiliary floating system and to perform the ballasting tests prior to the pre-installation of the rest of the tower and turbine on the foundation. The complete structure will be installed at the PLOCAN area, at 30m depth, in the North-East waters of Gran Canaria island.
Overall, the project will result in the first bottom fixed offshore wind turbine in Spain and in all of southern Europe, and the first one in the world ever to be installed with no need for heavy-lift offshore vessels or cranes, in a ground breaking step which paves the way towards new capabilities for low cost deep offshore wind. The main benefits expected are:
• 30-40% cost reduction (both CAPEX and OPEX).
• Large water depth applicability ranges for deep offshore (>45m water depth).
• Supports increased turbine size (5-8MW).
• Allows for large scale fast industrial deployment of foundations.
• Reduces dependence on costly and scarce installation vessels.
• Improved asset integrity (durability)

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

WP1 Project management: Project management activities have been performed to ensure the achievement of the objectives within time-schedule and budget constraints, by planning, organizing and controlling the integrated effort of the consortium and subcontractors involved in the project. The main objectives are to control the project to meet the schedule and deadlines (technical coordination); and to perform the financial and administrative tasks (administrative and financial coordination).

WP2 Design of the prototype foundation: This package covers the entire design of the foundation, following the requirements of the turbine manufacturer and the certification company. The objective is to develop the installation systems and processes, in order to produce a constructive project for the prototype.
The following deliverables have been submitted: D2.1 Design Basis for the prototype foundation; D2.2 Synthesis report of the complete Project for construction of the prototype foundation including Drawings and Technical Specifications. During the first year, the most relevant results of WP2 are summarized in these two reports that describe the design basis to be used for the detailed design of the complete gravity based structure and telescopic tower. The following points are covered by the deliverables: an overview of the foundation and tower, the fabrication process and the installation operations; the turbine design characteristics and parameters; the main properties and designations of the materials; the parameters to define the environmental conditions; and the temporary stages of the installation process and the environmental loads during the service life of the turbine. It provides load definitions for wind and wave actions independently and the set of load combinations to be used for design verifications.

WP3 Design of the auxiliary construction and installation means: WP3 designs the special and/or new equipment and tools required during all the process of manufacturing and installation. This work package runs in parallel with WP2, since both will generate crossed requirements.
The main results achieved so far are described in D3.1. Synthesis report of the complete project for construction of main auxiliary means for construction and installation. This document synthesizes the construction project of the main auxiliary means, describing the project background, the design process and showing the drawings to be followed for the construction. Details are provided for the following means: Dry dock excavation: pumping system installed in the perimeter of the dry dock, to keep the water table low enough; Foundation construction: some small cranes used to move material and to pump the concrete; Tower manufacturing and assembly: the prefabrication of the concrete pieces require steel moulds, as previously done by Esteyco in other onshore concrete wind towers; Turbine installation and pre commissioning: one of these two cranes will install the nacelle and the blades; Manufacturing of AFS: the AFS itself is a mean for the test and installation of the structure; Connection between tower and AFS: some tug boats are going to be required; Installation of the tower: a system of valves and pumps will introduce water inside the cells, to lower the tower to the seabed.

WP4 Construction of the prototype foundation: This covers the manufacturing of the prototype, starting in the dry dock, then placing the tower segments, installing the auxiliary buoyancy elements and finally the turbine. There is also an important part, which includes the manufacturing and placing of the moulds for the tower pieces. This is a key aspect of the project, since these pieces have to be very accurate to allow the telescopic erection. During the first year of ELISA project, the port pier working area has started to be adapted to admit the required cranes and loads that they transmit to the ground, H&S and quality plans have been defined, the earth dry-dock has been built and the first stage of prototype construction on dry-dock has been finished two months ahead of schedule.

WP5 Installation of the prototype foundation: All the processes and equipment needed to place the prototype in its final position will start in year 2.

WP6 Monitoring, data post-processing and certification: WP6 aims to test the process, check the behavior of all involved elements, the time required and, ultimately, generate a valuable demonstration for the market of the reliability and readiness of the prototype. The applied instrumentation will measure the reactions on the guiding system, the geometrical and verticality variations, and the stress on critical elements of the tower structure or the auxiliary buoyancy elements. During the first year, the sensors have been planned to be installed in the prototype foundation

WP7 Project dissemination paving the way to exploitation: This WP provides overall support to the project activities in every aspect that can impact the commercialization and exploitation of the project result through dissemination and communication activities. Specific objectives of this WP are: Communication to target audience in order to establish agreements with strategic stakeholders for exploitation; Dissemination in order to increase awareness on the new product and its functionalities compared to the best available technology (BAT) in order to highlight the significant advantages brought by ESTEYCO. During the first year of the project the following deliverables have been submitted: D.7.1. Communication and dissemination plan - communication plan, targeting the appropriate audience, once ESTEYCO acknowledges that one crucial part of the commercialization of the solution will be the establishment of relationships with the relevant stakeholders – prescriptors, partners and clients. Additionally, a preliminary dissemination plan has been defined be in order to increase awareness on the new solution and its functionalities, including the list of relevant industry events, several publications in magazines and the organization of events during the construction and installation of the prototype in the Canary Islands. In addition, D.7.2. Report on dissemination, communication and IPR actions – year 1 – will be delivered along with the periodic report.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

Europe is currently changing the energy sources, seeking reducing the dependence on fossil fuels. This strategy to increase the use of renewables energies was reflected on the H2020 programme, which provides funding to new technologies and concepts. One of the key technologies in the renewables area is wind energy, already with a large share in Europe´s energy generation. Onshore wind energy is very mature and locations with best wind resources are already occupied. Thus, offshore wind is increasingly prominent, since wind resource is unbeatable and visual impact is non-existent.
However, installation and maintenance costs in offshore wind are not competitive yet, so the market is looking for new solutions and is evolving to bigger and more powerful turbines, 8 MW and aiming to 10 MW in the midterm.
Current installation vessels are expensive and scarce, so the trend is the market is to reduce or even cancel the dependence on them, using concrete gravity foundations that serve as floating platforms. However, once the foundation is placed in the seabed, the large vessel is required to place the tower and the turbine. The concept developed by ESTEYCO goes beyond this point and removes the need of using any heavy vessel. The entire structure, turbine and systems are installed inshore, transported by a regular tug boat and installed by already existing means, with a much lower cost.
The new solution by ESTEYCO provides savings of approximately 30% in the installation costs, reducing the upfront investment for a wind farm. Moreover, it reduces considerably the maintenance costs, since concrete is much more durable than steel, and is a scalable solution, for turbines of any size and for depth range from 35 to 55 m.
All the technologies involved in the project have already been tested and widely used in marine and civil works, but never used in the wind energy sector. For this reason, it was necessary to build a demonstration prototype, in order to obtain the confidence of the industry and enter the construction of a complete wind farm. Furthermore, ESTEYCO’s solution is intensive in local labour and materials, ensuring a good reception from surrounding population.

Project beyond state of the art
ELISA project represents a major step to develop a new solution for the foundation of offshore wind turbines. The new concept is based in a gravity based foundation configured to act as a buoyant platform during the transportation and installation processes. This concept integrates as well a self-installing telescopic tower altogether with the complete wind turbine.
During the first year this unit has started to be fully assembled in folded configuration onshore in order to be towed to the site during the second year of the project. The system allows for an effective installation process inspired on a combination of proven technologies with an extensive track record in other sectors, aiming for a reduction of offshore works and completely avoiding heavy-lift vessels during the complete wind turbine installation process.
ELISA will allow the development of the first self-installing bottom-fixed offshore wind turbine to be commissioned in the world (continued through ELICAN project), which all by itself constitutes a great leap forward in the development and evolution of the offshore wind energy technology:
• Full independence of heavy-lift installation means
No bottom fixed offshore wind turbine has ever been built that did not require a scarce and costly (from 250.000 to 500.000 €/day) heavy lift for the installation of the foundation, tower and turbine in their final position. Some new unbuilt solutions are being proposed to allow for the craneless installation of gravity based solution; however, no substructure technology capable of avoiding the need of heavy lift vessels, not only for the foundation installation but also for the complete structure and turbine, has ever been released on the market. The advantages resulting in terms of savings, logistics and overrun risk in case on contingency or delay are immense.
• Less work offshore, more work onshore
This can be considered a golden rule of any low risk solutions with high capacity for industrialization which intends to be successful and reduce installation costs in the very demanding offshore environment. The present technology allows for a full onshore preassembly of the complete system, including all tower internal elements, and the pre-commissioning of the turbine. This is a key attribute to generate a highly industrialized manufacturing process with high production rates and optimum risk control, particularly when it can be produced with low-draft (<9m) low-height (<60m) low-width (<40m) requirements.
The telescopic configuration not only allows for disruptive advantages in the offshore installation process, but it also greatly eases the onshore assembly works by lowering the working height for the installation of the heavy wind turbine (note that the existing harbour and dry-dock lifting equipment is prepared for large weights but not for large heights). Therefore, the telescopic tower system also overcomes height and size limitations for the onshore assembly of the complete integrated system and ensures the scalability of the technology for the next generation of very large turbines and rotors.
• Profit from the robustness, economy and durability of concrete
The multiple advantages of structural concrete are backed by decades of proven suitability of this material in the Oil & Gas industry and in all types of Civil structures (Ports, Immersed Tunnels, Bridges, floating docks). It is however, a potential yet to be exploited in the wind offshore sector as it moves into deeper locations, with the capacity to provide competitive advantages such as:
• Great economy
• Focus on a strong, competitive and less stressed supply chain
• Pre-casting for high industrialization and production capacity.
• Durability for extended service life of the infrastructure and improved asset integrity

Expected potential impact
When completed, the project shall provide a highly developed solution with the potential of qualitatively reduce the costs of deep offshore wind while simplifying the installation process, avoiding the dependence on any large auxiliary offshore crane or vessel, and allowing for industrialised on-shore focused construction and better risk control and mitigation. The technology can significantly contribute to the industrialization capacity and cost competitiveness of an industry which is key to provide EU with the capacity to generate large enough amounts of locally sourced renewable energy, which improves EU energy security and contributes to the gradual solving of global climate and energy challenges.
• Impacts regarding cost reduction of renewable energy
Decrease costs of production and installation: In terms of cost, available predesigns confirm the potential of the technology to provide qualitative savings, based among others on the reduction of required material and installation means.
Decrease Operation & Maintenance costs and improve Asset Integrity: The concept proposes the use of concrete in the foundation and a major part of the tower as an economic proven material for robust and reliable marine constructions. Based on experiences both in the construction of Oil&Gas floating platforms and an extensive use of concrete as part of wind turbine substructures, both onshore and offshore, concrete has been broadly proven as a durable, fatigue resistant and virtually maintenance-free structural material, specially fitted for the harsh and demanding offshore environment. Using concrete as base structural material for the substructure can be expected to provide a more reliable asset integrity and relevant savings in OPEX costs.
• Reducing life-cycle environmental impact

The concept of substructure to be demonstrated in the project will have direct impact in all the phases of the life-cycle considered:
1. The use of concrete is proposed in the substructure as an economic proven material for robust and reliable marine constructions, leading to a durable, fatigue tolerant and virtually maintenance-free substructure, specially fitted for the harsh and demanding offshore environment. Additionally, LCA2 studies suggest that energy requirements of concrete towers are 20-50% to that of steel towers and that the use of concrete has the potential to reduce the carbon footprint of the solution to target values ranging between 65 and 75% of the carbon footprint of equivalent steel solutions.
2. Greater durability and fatigue lifetime, combined with the floating substructure’s travelling and lowering capabilities, offer the opportunity for lifetime extensions and turbine repowering strategies for increased service life of wind farm’s infrastructure, thus leading to even greater reductions of the LCOE.
The proposed substructure also offers reduced environmental effects, with no noise emissions and simple and vessel free complete full decommissioning with no permanently left piles or similar elements. These sum up with the acknowledged potential of offshore wind to provide large amounts of renewable energy with the corresponding reductions of CO2 emissions.
a) Improving EU energy security
b) Making variable renewable electricity generation more predictable and grid friendly, thereby
allowing larger amounts of variable output renewable sources in the grid
c) Nurturing the development of the industrial capacity to produce components and systems and
opening of new opportunities
Manufacturing strategy of the ELISA technology aims for high levels of industrialisation and promotes local content intensive products, both in raw material and workforce, contributing to European growth, jobs and strengthened industrial technology base. From a regional point of view, all of the above add up with the intrinsic potential of offshore technology to open a competitive market in different regions of Europe, including the Atlantic and the Mediterranean.
• Strengthening the European industrial technology base, thereby creating growth and jobs in Europe
The ELISA results’ manufacturing strategy aims for high levels of industrialisation and promotes local content intensive products, both in raw material and workforce, contributing to European growth, jobs and strengthened industrial technology base. A major part of the substructure shall use precast concrete, allowing for high production rates, as well as high industrialization and quality levels through prefabrication. This is supported by Esteyco’s extensive and virtually exclusive experience in the design, certification, production and erection engineering of over 400 precast concrete wind towers at an industrial scale.

During the first year, the developments of ELISA project have attracted the attentions of local authorities and visit was organized counting with the participation of the Minister of Economy, Industry, Trade and Knowledge of the Government of the Canary Islands, Pedro Ortega Rodriguez, and the President of the Cabildo of Gran Canaria, Antonio Morales. The prototype, named after the Gran Canarian Engineer Mario Luis Romero Torrent (MLRT), is the final demonstrator of the ELISA technology. After the visit to the worksite, the act of homage to Mario Luis Romero Torrent took place, and the book on his biography was released especially for the occasion. The act was held at the premises of PLOCAN. Octavio Llinás, Director of PLOCAN, hosted this ceremony which was conducted by Javier Rui-Wamba, President of Esteyco and Esteyco Foundation (promoter of the initiative).

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