WINNER! Best Offshore Renewables Innovation at the 2017 UK Energy Innovation Awards. Synaptec beat the largest ever entry field to win this prestigous award for our Refase™ product.
By their nature, offshore windfarms are hard to reach so when something goes wrong it costs millions to locate and repair faults. And when we say Millions, we really mean it – a recent Carbon Trust OWA report cited an average repair cost of £12.5m and 105 days for the last seven UK offshore windfarm outages, suspected to be caused by faults in submerged cables. These cables are at risk because the seabed is a harsh and dynamic environment – tidal and sand movement, erosion, water ingress, and impacts are real factors in cable damage. The consequence is that entire ‘strings’ of turbines feeding substations out at sea, or indeed the whole offshore array, can be taken out of production for long periods of time while engineers are sent out to sea to find where the fault is, and then organise how to fix it. Any technology which helps to reduce that outage time and cost even by one day will represent a significant saving.
This is where Refase™ comes in; there are fibre optic lines already embedded within all the cables which link together all the turbines to their substations, and those substations back to the mainland. We use these fibres to bring back measurements from lots of remote, small, sealed and completely passive sensors installed in every turbine and all their connecting cables. This means Refase™ can spot faults up to 100 km away in a few milliseconds, isolate only that section of cable showing a fault and then permit any unaffected turbines to come back onstream. This is all done automatically in well under a second, compared to a typical response time of between 12 hours and several days taken by engineers sailing out to the offshore substation and manually finding faults.
This automated response and remote monitoring is all done thanks to a unique and patented combination of lower-cost monitoring technology, scalability and software;
Refase™ PCTs (Photonic Current Transducers) provide lower-cost monitoring for each intra-array cable by eliminating the power supply, copper, and telecommunication expense traditionally incurred at every sensor location.
Refase™ uses revolutionary photonic multiplexing to remote-monitor as many as 50 of these low-cost PCTs through only one standard, singlemode fibre – even if that fibre is already being used for telecommunications. This effectively creates up to 16 distinct protected sections per string at a lower cost than ever before.
Refase™ software instantly sends digital fault reports which refer to a specific intra-array cable. This enables controllers to focus on repairing faults, rather than finding them, resulting in greatly reduced outage costs and faster repair times.