|The Wave Hub primarily consists of four Power Connection Units (PCUs) and the Termination and Distribution Unit (TDU). Click to enlarge.|
The UK Government has given planning approval for the Wave Hub Project off the coast of Cornwall in South West England. The £28 million (US$56 million) project, developed by the South West of England Regional Development Agency (RDA), has now cleared its last major regulatory hurdle. Funding for the project has already been approved by the RDA.
The Wave Hub is a sea bed electricity “socket” 16 kilometers (10 miles) offshore connected to an onshore substation via a sub-sea cable. Companies developing wave energy technology will be able to plug into Wave Hub to test their wave energy devices on a large-scale basis before commercialization. Four companies have already been chosen to use Wave Hub.
|Rendering of a PCU. Click to enlarge.|
The Wave Hub consists of a Termination and Distribution Unit (TDU) attached to four Power Connection Units (PCUs, transformers enclosed in protective casing), anchored to the seabed at approximately 50m depth. A single 33kV-20MVA cable will run from the Wave Hub to the shore, buried where possible. The cable will be buried through St Ives Bay into the beach close to Hayle, and then taken under the sand dunes to the substation site by means of directional drilling.
The TDU is a completely passive device. The PCUs contain metering facilities and a low voltage supply from an auxiliary transformer to supply control and signalling equipment. Each PCU comprises:
A 11kV circuit breaker that protects the transformer 11kV winding in the event of a fault on the 11kV cable and protects the 11kV cable in the event of a fault on the transformer 11 kV winding;
A 11/24 kV transformer that steps up the voltage output from the WECs to that suitable for transmission; and,
A 24kV circuit breaker that protects the transformer 24kV winding in the event of a fault on the 24kV cable and protects the 24kV cable in the event of a fault on the transformer 24kV winding.
The four participants already signed up are: Oceanlinx; Ocean Power Technologies Limited; Fred Olsen Limited; and WestWave, a consortium of E.On and Ocean Prospect Limited, using the Pelamis technology of Ocean Power Delivery Ltd.
The Wave Hub could provide an estimated 20 MW or renewable electricity when fully commissioned.
The Wave Hub project will cover an area of sea measuring four kilometers by two kilometers and each wave device developer will be granted a lease of between five and 10 years in an area of approximately two square kilometers.
Up to 30 wave energy devices are expected to be deployed at the Wave Hub and will float on the surface of the sea. The Wave Hub is expected to be operational in 2009.