The company’s Aeolus installation vessel placed the first of 150 foundations at the project site, located 85km off the coast of Groningen.
The monopiles change in length from 59m to 73m depending on water depth,.
Van Oord CEO Pieter van Oord said: "We are pleased that after fourteen months following the financial close, the first Gemini monopiles are being hammered into the seabed, exactly as per the original planning."
The project, which is expected to be commissioned in 2017, is owned by a consortium consisting of Northland Power (60% stake), Siemens Wind Power (20%), Van Oord (10%) and HVC (10%).
It will feature 150 Siemens 4MW offshore wind turbines that will provide enough energy for 1.5 million people in the Netherlands.
Upon completion, the facility will yield 2.6TWh of electricity a year and reduce 1.25 million tonnes of CO2 emissions.
Gemini CEO Matthias Haag said: "The installation constitutes a milestone in the construction phase and has been realized as planned through close collaboration with our project partners."
The project will play an important role in achieving European Union’s Renewable Energy Directive, which calls on all member states to reach a 20% share of energy from renewable sources by 2020.
Image: Installing the first monopile by the Aeolus on 1 July 2015. Photo courtesy: Koolen Photography/Gemini wind park.
