Growth through Research, development & demonstration in Offshore Wind


GDP DEMO Day Successful

7 November 2019

On Friday the 1st of November the Gentle Driving of Piles (GDP) project hosted a demonstration day of the field tests at the second Maasvlakte in the Netherlands. On that day the use of a newly developed pile installation method based on simultaneous application of low-frequency and high-frequency vibrations was demonstrated. Over 100 visitors witnessed a successful test installation and attended the symposium in the afternoon with technical presentations about GDP and other related subjects within the Offshore engineering research group of the TU Delft.

The field tests are part of the GDP research project that aims to develop a novel pile driving technique that simultaneously improves drivability, reduces noise emission, and ensures that the soil bearing capacity stays intact. In this experimental campaign that is executed from October to December 2019, the newly developed GDP shaker is tested and compared to traditional vibratory and impact hammers. In total eight piles were installed of which four were driven with the GDP shaker, three by impact hammering and one by vibratory driving. At the end of this year the field test finishes, and the piles will be removed.

In the next 2 months the installed piles will be laterally loaded and the behavior of the soil around the piles is monitored. The highly instrumented pile and soil monitoring will provide a unique set of data which will be used to validate three new prediction tools. These numerical models will provide the required tools to be able to predict the drivability of offshore monopiles, the state of the soil during and after driving the piles, and the noise generated during gentle driving of piles. Next step is the development of the GDP shaker in an offshore full-scale test and in stiffer soil types.

GDP is a project within GROW, the joint research program in offshore wind that initiates research and accelerates innovations. Delft University of Technology (TU Delft) is coordinating the project with the following project partners; Boskalis, Cape Holland, Deltares, DOT, Eneco, IHC IQIP, Innogy, Seaway7, Shell, SIF, TNO and Van Oord. This project is funded by RVO and supported by TKI Wind Op Zee. 

Find out more about the project

Gentle Driving of Piles Demoday
Gentle Driving of Piles Demoday
Demonstration of Gentle Driving of Piles
Demonstration of Gentle Driving of Piles

Video of successful decommissioning slip joint connection

19 September 2019

Find out more about the SJOR project and the slip joint connection


After a year of successfully testing the Slip Joint connection, the DOT wind turbine is decommissioned

16 August 2019

With the removal of the DOT wind turbine all phases of this concept’s lifetime are investigated and successfully put to the test. 

Friday morning the 16th of August 2019 the wind turbine, outfitted with a Slip Joint connection, was successfully removed from its monopile foundation. 

The DOT wind turbine was located in Eneco’s Princes Amalia Wind Park off the coast of IJmuiden, the Netherlands. The complete wind turbine was picked up in a single lift from its monopile foundation to be transported towards and backloaded on the quay of Sif Rotterdam for further onshore decommissioning. Same as during the installation, the offshore removal of the wind turbine was executed by Heerema’s DCV Aegir being operated on its Dynamic Positioning System. This way of working in combination with the use of a slip joint connection is noticeably faster than current industry practice.

With the removal of the wind turbine all necessary data regarding the Slip Joint connection is successfully gathered and is now being processed and used for validating by the project partners.

Find out more about the project and the slip joint connection

DOT Wind Turbine
DOT Wind Turbine

GROW side-event at the WindDays - Foundation Innovation: Presentations are available now

13 June 2019

Did you visit our side event on foundation innovation at the WindDays and do you want to have an other look at the presentations? Or were you not in the possibility to attend and want to know more about foundation innovation?

During this side-event, GROW presented several new developments in the field of offshore foundations. The first (intermediate) results of three GROW projects were presented;

Find the presentations here

GROW side-event at the WindDays - Foundation Innovation

12 June 2019, 11.15 – 12.45, WTC Beursplein 37, Rotterdam, Leeuwen Room II

Interested in the developments in offshore wind foundations?

Please be welcome at our side-event on foundation innovation at the WindDays in Rotterdam on 12 June 2019.

During this side-event, GROW presents several new developments in the field of offshore foundations. David the Jager, director of GROW, will lead you through the program. The first (intermediate) results of three GROW projects will be presented;

The presentations will be followed by a discussion.

Find out more about the presentations


Let us know that you want to visit the GROW side-event by registering here.

Please note: You also need to purchase a WindDays Exhibition ticket to enter the GROW side-event. You can buy ticket to the WindDays exhibition here.

Maxim Segeren, Reinder Jorritsma and Ahmed Elkadi
Maxim Segeren, Reinder Jorritsma, Sander Suur and Ahmed Elkadi

Innovation doesn’t stop with subsidy-free tenders

22 March 2019

In the coming years, offshore wind energy in the Netherlands will get a big boost. By 2030, the total installed offshore wind capacity is planned to be 11.5 GW. Where a few years ago, offshore wind was seen by the general public as the most expensive climate solution, it has now become one that needs almost no financial support from the Government. Technological and non-technological innovation have contributed significantly in bringing the cost of offshore wind energy down. With offshore wind being more competitive, do we still need to invest in innovations in this area? The answer is YES!

Wind Energy Magazine spoke to David de Jager, director of GROW, a consortium of about 20 players in the Dutch offshore wind energy industry that work towards bringing down the cost of offshore wind and increasing the role in the energy system by exchanging knowledge and intensive cooperation. 

You can find the complete interview with David de Jager here.

David de Jager
David de Jager

First offshore wind turbine using the Slip Joint connection successfully installed

30 September 2018

SJOR project tests innovative connection offshore: ready-to-use installation within an hour.

This morning the DOT wind turbine was successfully installed on its previously installed monopile using a Slip Joint connection. The Slip Joint is an alternative connection between an offshore wind turbine and its foundation. It works and looks like two paper cups upside down stacked on top of each other. The connection is based on friction, where the weight ensures a firm and stable connection. Installation is done by simply sliding the wind turbine over the monopile without the use of grout or bolts. This simple mechanism allows for cost reduction in material, equipment & personnel as well as allowing for a shorter installation time. It is the first time a slip-joint connection is deployed offshore. 

The DOT wind turbine is located in Eneco’s Princes Amalia Wind Park off the coast of IJmuiden, the Netherlands. The complete wind turbine was picked up in a single lift by Heerema’s DCV Aegir from the quay of Sif Rotterdam and transported towards its designated location. The installation of the wind turbine took within an hour in total, which is noticeably faster than usual installation. Jan van der Tempel, Director of DOT BV: “This offshore installation is a major milestone in the commercialisation of the Slip Joint.” The wind turbine will stay offshore for a year to test and collect data regarding this innovative connection after which the gathered data will be processed and used for validating lab tests by both TU Delft and TNO.

Find out more

Installation slip joint connection magnify
Installation slip joint connection
Installation of turbine with Slip Joint connection

GROW and the Ministry of Economic Affairs and Climate Policy sign collaboration agreement to strengthen innovation in offshore wind energy

22 March 2019

Offshore wind energy is a key technology in the transition of our energy system towards sustainability. This is demonstrated by its dominant position in several energy agreements and reports on the energy transition. Also the draft Climate Agreement is heading in that direction. GROW, the consortium of leading Dutch offshore wind industry and research partners, is working hard on the required innovations to fulfil this important role. The Ministry of Economic Affairs and Climate Policy fully supports GROW. “The Dutch offshore wind sector represented in GROW is leading the way.” said Sandor Gaastra, Director General Climate & Energy at the Ministry of Economic Affairs and Climate Policy. “That is why my ministry signed a collaboration agreement with GROW. With this agreement we will further strengthen the position of offshore wind energy and of the Dutch wind sector.”

GROW is contributing to the energy transition by working on the societal task of making the energy supply more sustainable. It carries out a coherent program of Research, Development & Demonstration (RD&D), ranging from more fundamental research to the demonstration or rollout of offshore wind energy innovations. Research questions within the program include: How can the wind turbine installation process be improved further, at lower costs? How can the environmental impact of noise, for example, be limited or even be prevented? How can maintenance activities be carried out as effectively and efficiently as possible?

Sandor Gaastra: “Due to the intensive cooperation and knowledge sharing within GROW, with parties representing the entire offshore wind value chain, successful innovations can be realised relatively fast. GROW is therefore an interesting discussion partner for us and we are happy to formalise this cooperation.”

Chairman of GROW Peter Terium: “To achieve the energy and climate goals, the government, industry, knowledge institutions and civil society organizations must work together even more. That starts with innovation. This agreement helps us to keep up the pace of innovation. "

Signing of the collaboration agreement
Signing of the collaboration agreement
Signed collaboraton agreement a magnify

David de Jager is GROW’s new Director

15 May 2018

As of today David de Jager succeeded Ernst van Zuijlen as Director of GROW. After being responsible for the programming of RD&D on offshore wind energy for about ten years (as Director of FLOW, TKI Wind op Zee, and GROW) Ernst will pitch into both product- and project development in the same area.

David de Jager comes from consultancy firm Ecofys and has almost 30 years of experience in renewable energy, notably on the interaction of technology development, policy design, and finance. Over the past decade he acted as Operating Agent for the IEA-RETD, an international research program of the International Energy Agency.

David de Jager
David de Jager

GROW consortium officially launched at Wind Days 2016

The GROW consortium was officially launched at the WindDays 2016 conference held in Rotterdam, the Netherlands. This consortium of leading Dutch companies and knowledge institutes involved in the offshore wind industry has created an innovation programme that aims to reduce the costs of offshore wind energy.

GROW launch during WindDays 2016
GROW launch during WindDays 2016