Scandia foundations, turbine assembly and deployment
David Roseman, MD
August 18, 2010


The following is my understanding of Scandia's proposal for building and deployment of the foundations and turbines, and of the problems related to Lake Michigan.

Scandia has consistently said that they plan to avoid the Jones Act, a federal act requiring ships carrying goods between US ports to be US-built. They would do this by avoiding the need for offshore cranes to rig the turbines. As I understand it, in order to lift turbines and blades offshore, it is necessary to use jackup ships, which have legs that sit of the bottom. I don't think any of these exist that will work in greater than 40 meter depths [1] [2]. Perhaps one could be constructed, but it would be extremely expensive. At the August 4, 2010 meeting at Hart Middle School, Mr Dirdal confirmed that he did not propose using a jackup ship.

Scandia has consistently said that it proposed using concrete and steel foundations based on the technology of a Norwegian company named Vici Ventus. The foundations are poured from a floating platform, and lowered into the water as they cure. The turbines and blades are then attached to the base. Since the platforms are hollow, they float. The entire assembly is then towed to its destination, flooded, and ballasted.

To do this requires very special construction conditions. The body of water needs to be deep enough to accomodate the full height of the foundation, and sheltered enough to allow crews to work for substantial periods of time. The technique is well suited for Norway, and the company says on their website that its technology is meant for the Norwegian fjords. In Vici Ventus' words "...the turbines can be mounted in a fjord before it is towed to the site where it is installed using ballasting." [archived]


From Scandia's June 16, 2010 Powerpoint presentation, slide 21


The following further substantiates Scandia's intention to use the above approach.


Havgul Clean Energy, is taking a different tack altogether and purports having found a solution that eschews the need for new or retrofitted specialists vessels entirely.

"The Jones Act is a killer for current technology in the US, but that doesn't mean it kills offshore projects - it just means you have to move towards more economically feasible solutions," says Dirdal.

Havgul Clean Energy proposes complete wind turbine assembly onshore before tugging the entire structure offshore - using Jones Act compliant barges - and completing the installation process using ballasting.

The concrete foundation technique, developed by fellow Norwegian company and inveterate oil and gas industry trailblazers Vici Ventus, is applicable at depths between 30-100m.

According to the company, it significantly reduces risk and costs associated with transport (no heavy vessels, no cranes, no lock system nightmares), and seabed preparation, while the installation itself allegedly has minimal impact on marine life.

As the foundation cost is fixed, the solution also favours big turbines.

"We believe that our proposed approach is the future, not just in the Great Lakes but anywhere in the world - it doesn't make sense to put the turbines on top of the foundations at the final site," says Dirdal.

At the August 4 meeting, I asked Mr Dirdal where he proposed building the platforms. The problem is that Lake Michigan has no place with conditions like the fjords. Our harbors are generally fairly shallow. They are conected to the Lake by channels that are fairly narrow, and less that 30 feet deep.

At the August 4 meeting, Scandia and POWER had placed laptop computers on the stage. The facility's projector was used, and whomever was presenting would attach the video cable to their computer. I had put my laptop on the stage, and was projecting a few slides which helped to illustrate my questions. I had just projected a chart of Muskegon Harbor, taken from NOAA chart 14934. The purpose was to show that the maximum depth is about 79 feet, and that the channel is about 220 feet wide and 26 feet deep. Mr Dirdal grabbed the cable from my computer, and attached it to his. He said that the foundations would be built "up north" in "Kalamazoo."

This raises several problems. First, Kalamazoo is not north of Hart. Second, it is inland, and connected to Lake Michigan by a narrow river. He obviously misspoke. But where "up north" could he have meant? The only place I can think of is the Manitou Islands, since Manitou rhymes with Kalamazoo. There is some deep water west of the Manitou Islands (see NOAA chart 14902), but it is certainly not sheltered. Perhaps he had another location in mind. After the meeting, I asked Mr Warner if he could email me the name of the proposed construction site before the Planning Commission meeting the following day. He said that he didn't think that he could. To the best of my knowledge, no site was sent to the County before the August 12 Board of Commissioners' meeting, and none to date.

Finally, the Manitou Islands are part of the Sleeping Bear National Lakeshore. This might pose some problems for a major, multi-year construction project.

To give some perspective, I had planned to show a Google Earth view of the Muskegon channel


and a Tom Sturr drawing showing the difficulty of floating a 90 story tall structure through the channel.

The specks on the base are scaled to represent people. The structure, of course, would be stuck on the bottom.

There are two important issues. First, it is possible that the project that has been proposed, and which has cost our area so much to oppose, could never have been constructed. Second, Scandia promised 2 million man-hours of local labor to construct the platforms. From their May 2010 Powerpoint presentation, Slide 20:



These jobs were to have been in Ludington, then Muskegon. Where now?

Scandia made a comment about "armchair engineers." It wwill be interesting to see the response from their "real" engineers. Armchair or real, we are all constrained by the same laws of physics.