Listening with Light

The need 

Typically, only 30% of oil and gas reserves are recovered from an oil field beneath the ocean floor. Increasing recovery by only 2-3% could be worth more than $1bn for the average field. As we approach the end of easy-to-access oil and gas worldwide, more cost-effective technologies are needed to improve the recovery of existing reserves to 40%, 50% or even 60%.

The results 

To identify untapped oil reserves, companies build detailed 3D images of offshore fields. The seismic data is obtained from sensing systems which measure sound waves. These are transmitted through the earth and reflected back from the various layers of rock. But conventional electrical systems are costly, prone to failure and have high maintenance costs. They can also be a safety hazard. Developed with the help of more than £1m from the Technology Strategy Board, the Fosar® system does not need subsea electrical power and could now provide a more reliable and cost-effective way of maximising oil and gas recovery.

By commercialising a fibre-optic technology first developed in the UK for anti-submarine warfare and security purposes, British company Stingray has shown how operators can ‘listen with light’ to detect levels of oil and gas beneath the sea. The Fosar system consists of a permanently installed network of optical sensors (potentially running hundreds of kilometres across the sea floor) which send signals to recording equipment above. The sensing arrays are small, lightweight and easy to install in deep water and around subsea installations.

A series of successful trials was held in the North Sea which led to the commercial launch of the Fosar system in May 2009. As oil reserves dwindle the race is on to extract what’s left. With the market for permanent oilfield monitoring estimated to be worth between $500m and $1bn a year by 2015 it is no surprise that the venture capitalists and oil companies who have already invested more than £10m in Stingray are watching future product developments keenly.