So to finish off, once all 3 bearings have been replaced, the hub is lifted back onto the back deck, the blades are all reattached in reverse order, like this.
After all blades are attached the nose cone is put on, the HLB attached and the temporarily steps removed, the main lift commences.
Check out the shadow, I like this shot.
Blades attached and the guys have earned a rest, but not a long one, as soon as we jack down and the tides are right we will be moving onto the next turbine.
I would like to thank Fugro Seacore for the hospitality they showed me onboard the Excalibur, a great bunch of hard working guys/Girls and best of all, the food was fantastic.
The Arklow Bank Wind Park is the first offshore wind farm in Ireland and the world’s first commercial application of offshore wind turbines over 3 megawatts in size. It is located on the Arklow Bank, a shallow water sandbank in the Irish Sea, around 10 kilometers off the coast of Arklow with an area of 27 by 2.5 kilometres.
The project is being co-developed by Airtricity and GE Energy. In 2002, Airtricity obtained an offshore lease for a 520 MW offshore wind farm. The first phase of the project, commissioned in June 2004, consists of seven GE 3.6-megawatt generators. They were installed by the Danish offshore wind farms services provider A2SEA. Power cables were laid by Five Oceans Services. All of the turbines have a height of 73.5 metres (241 ft) and height to top of blade of 124 metres (407 ft). The blade length is 50.5 metres (166 ft) and each turbine has three blades. Each turbine weights 290 tonnes.
Now we are at the correct height we can start the lift, Once the GE guys are in place inside the turbine, we connect the heavy lift bracket to the crane hook and it’s lifted to the top of the turbine.
You can just make out the GE guys connecting the HLB, once thats connected they will undo all the bolts holding the blades in place from the inside.
Around the same time a lifting strop is connected to the number 6 blade (think of a clock face) for the other crane.
All nuts removed the blades and hub are slowly removed.
Now a great bit of crane ballet is performed and you can see why the barges have to be positioned so exact.
Blades are manoeuvred between the legs and pedestal with great skill.
The blades are slowly lowered onto a fixed base on a movable deck at the rear of the barge.
This base is used to secure the hub for the removal of each blade.
Success, Mark the project manager is a happy man. 1st stage complete.
I’m back in the land of the internet, no silly limits anymore, I actually got back last week but the wife and I headed off to Bruges for a few days R&R.
So this wind farm business! Why? How? I’ll try and explain.
First of all there are two barges, The Excalibur and the Deep Diver, these have to be positioned in such a way, with about 50cm tolerance so we can use both cranes at the same time, this is very important which will become clear in later posts.
We can only move these barges at slack water (In between tides) as the current is very fast because the water is so shallow, a couple of meters in some places. First we move the Excalibur and about 6 hours later the Deep Diver, we use two boats, the Valiant and the Sergeant Pepper.
Here’s the Valiant.
And the Sgt Pepper.
Photo by Sydney Sinclair
We use the Valiant to tow us close to the location with help from Sgt. Pepper, then the Valiant is released from the tow and with help from Sgt. Pepper we walk the barge onto it’s final location, this is done by placing one leg on the seabed and with the Sgt. Pepper pushing or pulling we swivel around that leg, we will then drop another leg and do the same again, a little bit of tweaking and we are there.
Here is the Deep Diver on location at one turbine, the Excalibur has already been moved off to the next turbine.
Coming alongside the Excalibur for my lift off by Billy Pugh, you can get an idea of the scale of the job at hand.
Now some of you may have noticed the cranes don’t seem big enough to reach above the turbine to remove it, more on that tomorrow.
Well it’s a big day today, Hank gets painted today, and will I be there to see it go down? No, will I check it out tomorrow or the next day? No, you see on Wednesday I had to go to work and as you should know by now it’s not a 9-5 job, so Wednesday morning I catch a plane to Dublin then a hire car to Arklow which is on the east coast of Ireland, I stayed in the Arklow Bay Hotel the night which was very nice. The following morning I was on a boat to my next place of work.
And this is it.
Home for the next 3 weeks or so.
We will be taking the turbine off, then the blades and replacing a bearing and putting it back together again, 7 in total and so far 3 have been done, we have two jack up barges on location and they both have to lift and juggle the turbines into place so ill be taking lots of photos and go through to process later, so watch this space.
The only drawback is they only give me 500mb of data a month and I will be using most of that on this post so you will have to wait until I get back home, I should be out here for about 3 weeks.