Lupus Engineering Services Ltd
Specialists in Marine Renewable Energy
Novel Solutions for Installation & Retrieval
The following examples were developed by Lupus Engineering in conjunction with Tadek Offshore and Dynamic Marine Systems as robust, yet novel, installation and retrieval solutions for the tidal energy industry that do not rely on jackups and DP vessels, and also minimise the need for ROV intervention.
A lift frame with controllable buoyancy tanks enables the required offshore crane capacity to be vastly reduced. In theory this could mean that nacelle installation and retrieval could be done with something the size of a Multicat.

This solution would likely work best if there was an available shore-side slipway to enable the transfer of the turbine between land and sea to be undertaken without the aid and expense of a heavy lift shore-side crane.

In the absence of such a slipway - the lift frame here would have to be strong enough to also take the dry weight of the nacelle and lift frame which would not be so attractive.

This idea gave birth to another idea, see below, whereby the lift frame and buoyancy are seperable.
Alternative Buoyancy Solution
In this solution the buoyancy is provided by a raft built using caged air-bags. The lift frame that sits in the middle is detachable so that a shore-side crane capacity does not need to include the weight of the buoyant elements.
The raft solution shown here is designed to be used with nothing more than a multicat. A sheave block arrangement on top of the lift frame gives sufficient mechanical advantage - that a multicat winch has sufficient capacity for raising or lowering the nacelle with the raft.