The Channel Cable interconnector system consists of two (2) power cables and one (1) fiber optic cable that are bundled together. Each power cable is made specifically for High Voltage Direct Current transfer and its strength and flexibility are ideal for a submarine cable. The cable consists of steel armor and solid flexible plastic to protect and insulate the copper wire. It measures approx. 12cm in diameter and contains no insulating and/or cooling fluids.
- Already proven in similar privately owned merchant projects
- No fluctuating electromagnetic field
- Not oil or liquid cooled
- 100% Low environmental and visual impacts
Cable Installation Equipment
For a safe and minimal impact cable installation
How the Channel Cable will be installed on land and under the seabed
Submarine Cable Installation
Tailor-Made Plan for the English Channel
Both cables of the Channel Cable interconnector system are laid together. The submarine cables have steel armouring to help protect them.
Installation of the cables is scheduled to minimise environmental impacts. For example, so as not to interfere with critical fisheries and fish spawning seasons.
How It Is Done
In preparation for cable laying, the seabed is surveyed with a remotely operated vehicle (ROV) to ensure cable lay safety and to confirm the seabed data gathered during the lengthy route planning phase. Additionally, in some locations along the route, the strategic placement of coarse gravel is necessary to create a stable base on which the cable can rest. In some other locations an underwater plough will create trenches for additional cable burial protection. Where additional cable protection is deemed necessary at certain locations along the route, large rock boulders will be placed over the buried cable areas.
Overall the target burial depth for the cables underwater is 1 metre. On board the cable vessels, the construction cycle is made up of several steps including trenching, rock cutting, testing and the lowering of the cable onto the seabed.
There are exact procedures defined for each process to ensure quality and compliance with health and safety regulations. Following the laying and burial process, the cables were again monitored underwater by ROV to ensure correct positioning.
Land Cable Installation
Terrestrial cable routes are subject to a route selection was based on:
- Environmental studies
- Technical feasibility
- Low environmental impact
- Existing utilities
Using areas that are already designated as utility rights-of-way reduces disturbance to the environment. Because the cable will be buried, there is no visual impact and continued transportation, recreation and agricultural usage of the overlying land will be unchanged.
Horizontal directional drilling (HDD) will be used for the transition from the terrestrial to the marine environment. Drilling underneath minimises the disturbance to marine foreshore areas. As a result, the intertidal zone would be undisturbed by cable installation.
HVDC Convertor Stations
Converting AC electricity to DC
Converter Stations will be constructed near the existing substations in Sussex in England and Paluel, Normandy in France to enable the transfer of energy between the DC cable and the existing AC grids. These converter stations require a relatively small area and are easily modifiable to be visually compatible with their surroundings.
A typical converter station consists of an enclosed building for the converters and the control system, AC reactors, a harmonics filter and a cooling system. The converter stations are virtually maintenance free.
Environmental and aesthetic considerations
Noise: The converter station would emit minimal noise and would meet all local statutory requirements for noise. We have experience in designing converter stations to include features that minimise noise.
Construction: Construction would take place during daytime hours to reduce noise impacts, and would last approximately 7 months.
Safety and Security: The converter station site would be fenced and secured during construction and operation. Geotechnical and seismic studies would provide design criteria to meet structural and earthquake standards.
Design: Converter stations can be designed to fit into their surroundings, incorporating features consistent with existing structures in the area.