Carbon Trust: Off shore Wind Accelerator (OWA)
Carbon Trust: Off shore Wind Accelerator (OWA)
Carbon Trust is a UK organization that aims to accelerate the introduction of the low carbon economy by collaborating with industry to reduce the cost of renewable energy technologies.
The OWA is collaboration between the Carbon Trust and originally five a international energy companies with licenses to develop 60% of the UK’s offshore wind capacity. There are four research areas, foundations, access systems, electrical systems and wake effects, and the aim is to reduce the cost of offshore wind by 10%. The foundations competition has the objective of reducing lifecycle costs for offshore foundation structures by 10-20%, bringing it down to £0.4-0.6m/MW. The original five energy companies are: SSE Renewables, Statoil, DONG Energy, RWE Innogy, ScottishPower Renewables. Later Statkraft, Mainstrean and E.ON joined the project.
- Foundations for 30 to 60 meters of water depth
- £30 mio. for demonstration projects
- Manufacturing costs
- Transport and installation costs
- Potential for volume cost savings
- Structural durability
- Maintainability and turbine accessibility
Out of the seven shortlisted concepts, OWA chose four for further development and potential large scale demonstration. The four concepts must further qualify risks, installation, production, and maintenance costs of their concepts.
BREAKDOWN of CAPEX
CAPEX is short for Capital Expenditure. This covers the costs including the wind turbines, foundations, trafo station etc.: 4% development and consent, 15% electrical, 22% integrated support structures, 26% production, installation and commissioning, 33% turbine.
Source: BVG Associates and Carbon Trust.
Collaboration and the sharing of experiences can take wind farms to the next level, according to Helge Gravesen, technical project leader of the Carbon Trust’s Offshore Wind Accelerator (OWA) foundations competition, Stage 1. He has experienced the benefits of cooperation in a sector that is normally marked by protectionism.
By Anne Korsgaard
In the future, offshore wind turbine farms must go deeper and further offshore and they must be cheaper to produce, install and maintain. Experts estimate that between 30% and 40% of the cost of an offshore wind turbine farm goes into the foundations. The Carbon Trust, a UK non-profit funded mainly by the British Governmental, has decided to minimize the cost of offshore wind energy under the slogan: working together to accelerate the development and deployment of new technologies. For Helge Gravesen, who has worked in the offshore sector for 32 years, working together is central in moving towards the best and cheapest solutions.
- It is groundbreaking for this sector to gather some of the world’s largest energy companies and the best designers in a common development process like the one created for the Carbon Trust’s Offshore Wind Accelerator (OWA) foundations competition, he says and continues:
- What we see at present is a sector that is finally maturing through joint industry development projects, which have been a tradition over three to four decades in the offshore oil and gas sector. And it is absolutely crucial for the development of cheaper and more cost efficient foundations that we bring experts together in an atmosphere of openness. Through the Offshore Wind Accelerator initiative (OWA) the Carbon Trust has created a platform for research cooperation between eight of the major energy companies driving the offshore wind development.
Creating opportunities for the sector through synergy
Phil de Villiers is the overall responsible for the Offshore Wind Accelerator activities. In his opinion, one of the big successes of the OWA project is that there has been a very open discussion and exchange of experiences concerning the technical issues, risks and challenges between the energy companies as well as between the designers.
- It makes sense for everybody in the project to share knowledge because there is a common goal: to reduce costs. Each of the 90+ people in the project have different experiences and skills, which means that one person in the room may be able to supply a solution to a specific challenge that an innovator is facing. For example, two of the concepts included suction buckets: MBD Suction Bucket Monopile and the SPT Offshore & Wood Group self-installing tri-bucket (see next pages of this magazine). One of the challenges that they have in common is to determine whether there are boulders in the seabed that could compromise the performance of the suction bucket during installation. One of the designers came up with a technology that could analyze the seabed to identify boulders, which the other concept designer could immediately adopt. They have been able to advise each other and search for solutions together thanks to the cooperation in OWA.
But how is it possible to produce an environment of openness and willingness to share knowledge when competitors are seated around the same table? Jørn Scharling Holm, Technology Development Manager, Renewables, at DONG Energy explains how he sees the success of the competition:
- All the energy companies have similar goals: to reduce costs of offshore installations. If we succeed in attaining that goal, the cake will be larger for everyone involved. So we can all see an advantage in getting wiser. But at first there was a great deal of work involved in creating the right framework for an open coopetition, as we call it, when competitors cooperate. In order to make the involved parties feel safe in sharing their experiences and knowledge there must be signed IPR’s and legally binding agreements on what can be said within the project group and what can be shared outside the project, he says and continues:
- It makes a great deal of sense for DONG Energy to participate in the OWA: Now we have a catalogue of ideas to improve future offshore wind installations.
Helge Gravesen, technical project leader of the Carbon Trust foundation competition, Stage 1
Cooperation out of necessity
The Carbon Trust OWA foundations competition has encountered several situations where the will to cooperate was important. Helge Gravesen explains this with an example:
- Of the 104 competing foundation concepts submitted to the project, two were so alike that they could not be granted separate development funds. We had to find an alternative solution.
The gravitation foundation – submitted by both French Freyssinet and British Gifford/BMT - represented good opportunities for a cost reduction. Carbon Trust decided to grant the gravitation concept funds for the large scale demonstration provided that they work together.
At a larger scale and outside the Carbon Trust’s OWA, joint industry projects within the oshore wind sector are also emerging out of necessity.
- Another example is the grouting problem in monopiles. At several wind farms the concrete grout that is used to join the monopile to the transition piece is developing cracks. This has turned out to be a general problem in many installations and several energy companies such as DONG Energy, Vattenfall, Statoil and E.ON, took the initiative to gather up their specialists in order to analyze the problem jointly. It was crucial to find a solution both for the cheapest way of repairing the offshore installations and for avoiding the problem in new installations. As a result of the joint effort, it turned out that the general design conception used up until now was unsafe and the concrete grout design had to be altered.
The Carbon Trust initiated the Offshore Wind Accelerator in October 2008. The organization is addressing four of the major challenges for third generation offshore wind turbine farms: 1. Electrical systems, 2. Foundation concepts, 3. Wake effects and 4. Access, transportation, and logistics. For the foundations competition the demands are that they must be suited to 30 to 60 meters of water depth and the CAPEX (Capital Expenditure) must be reduced to between £ 0.4 and 0.6 mio. pr. MW.
Helge Gravesen, who also works as Chief Consultant at Grontmij|Carl Bro, ports and marine engineering and loads, gives the status:
- Out of 104 foundation concepts, seven concepts were supported for conceptual engineering. Based on the results of the conceptual engineering including a risk and cost analysis, four concepts were selected for further development. In addition, a “reference 4-legged jacket” was studied to provide a conventional concept cost reference. Instead of initiating installation of test structures after the conceptual stage, the participating energy companies decided to insert a “derisking and detailed installation and fabrication costing phase” for the four concepts plus the reference jacket to further qualify their concepts, focusing on the potential risks and costs of their design, the project leader explains:
- For instance, the bucket suction foundation from MBD has to give additional information to confirm that they can actually safely install the buckets in various types of soil with varying soil conditions over the entire depth.
Mark Riemers, Managing Director of SPT Offshore - one of the winning designer companies - considers joint industry competitions to be a very important factor in creating foundations for the future:- We consider that additional R&D such as the Carbon Trust project is required to go back to basics and to investigate every possible way to reduce costs. Cooperation has been very good and all parties have been very open in explaining their expertise and tricks.
Helge Gravesen is glad to see that the sector is finally maturing to a degree where the parties are starting to cooperate in finding the best and cheapest possible ways of making offshore renewable energy. The potential benefits from the optimization of offshore wind foundations are very large for offshore wind due to the many foundations in each wind farm.
And he makes a final point:
- It is not rocket science to optimize an offshore wind farm, but we are taking on optimizing all design parameters one or two more times to obtain competitive energy prices on offshore wind energy.
Read more about the four foundation concepts on the following pages of this magazine and visit www.carbontrust.co.uk