Our project

Our method

Distributed Temperature sensing (DTS) in deep ocean is executed using an armored fiber -optic cable in combination with an onshore facility that measures and processes data.

For a measurement, a pulsing laser light is emitted into the fibre optic cable. Throughout the cable the laser light is reflected by imperfections in the glass fibres. The reflected signal is analyzed for Raman backscatter. Raman scattering produces two broadband

components, the so called Stokes and anti- Stokes emissions, at higher and lower frequencies than the main reflected signal. The ratio of the temperature- sensitive anti –Stokes intensity to the insensitive Stokes intensities is the basis of the DTS temperature measurements. These temperature measurements are needed to investigate the potential and rendement options for a OTEC system.

Our project

The project is focussed on the design of a suitable fibre optic DTS configuration used for ocean thermal energy conversion. DTS uses the backscatter of light sent through a fibre optic to infer temperature variations along the cable. This cable need to be deployed at the desired location. In this project the whole DTS system will be designed.

A team consisting of 5 students will go to location to acquire necessary local information. This information, combined with the information gathered from many different instances in the Netherlands, will result in a complete installation plan. The 2 months at location will be spent gathering missing information, engaging with local stakeholders and tackling technical challenges. To come to a complete design- and installation plan research needs to be done. Some aspects that needs to be investigated are: The dynamics of the buoy and mooring line considering all the load cases and different forces, the dynamics and forces on the cables and boat during installation, logistics, an economical-, risk- and multi criteria analysis, stakeholder mapping, local permissions, planning and guidelines for installation, planning for removing the equipment.

As can be seen this project has several interesting technical challenges that need to be tackled. The most interesting challenges are summed up below:

In which way will the cable come to land in rough conditions at the coast?
How to determine the exact location of the cable during its lifetime?
What are the environmental, static, accidental, installation and extreme loads on the system?
What are the horizontal deviations of the vertical mooring line due to the current?
How long will the system be operational?
In which way could this system be removed safely?
What are the risks during the installation of the cable and during the operation?
Is the installation worth the investment?

When the design phase is ready and the configuration of the DTS system is known, the mobilisation, installation and operation of the DTS system is prepared. Thereafter, the equipment will be installed on site with the help of Bluerise BV and local technicians. Then the actual measurements will be performed and verified. The experiences and results gained from this study are crucial for a feasible and ecologically safe implementation of ocean thermal energy solutions.