February 2017

Thermal Energy Recovery System

Exnics has successfully developed and tested a subsea Thermal Energy Recovery System, a completely new product class for subsea production systems. The system is currently TRL6 (API17N) and field testing is ongoing on a North Sea oil well, 160km off the coast of Aberdeenshire, gaining field history every day.

The nonintrusive technology fits around subsea production flowlines as a two piece ring. It harvests geothermal heat from produced fluids and converts this heat to DC electrical power. The product is standardised to suit nominal pipe sizes and is compatible with subsea paint/coating specifications.

The technology has no moving parts and runs in a steady state thermal condition. It includes the ability to track any transient changes in the heat source and heat sink and will adjust itself accordingly to maintain peak power output in all conditions.

The technology is packaged in a building block product design lending itself to fully scalable systems; any number of units can be connected together providing for a wide range of applications from mW to kW, from sensors to electric valve actuators. Larger systems can be connected as electrically parallel clusters providing inherent redundancy with no single point failure.

The products:

Hot Rings (greenfield solution)

Hot Rings are the world’s first Subsea TERS. They are installed onto subsea production flowlines whilst onshore, prior to the flowlines being deployed, so the TERS is installed and commissioned with the flowline without the need for additional deployments [once at sea]. Multiple Hot Rings can be connected together providing a truly scalable solution with a single standardised product.

Talon (brownfield solution)

The Talon is an ROV / diver deployable tool that delivers TRS to brownfield projects. Once installed onto a subsea flowline Talon generates DC power and can be supplied with an integrated rechargeable battery. This tool provides a deployment and power platform for the installation of remote sensors and wireless communications. Talon provides an important step towards the subsea internet of things.

Rechargeable Subsea Battery

Energy storage solution, our subsea battery system is built on the latest rechargeable battery chemistry, LiFePO4, this chemistry is more stable and safer than Li-Ion, resulting in 10x the cycle life. The ability to recharge subsea batteries in-situ allows for much faster sample rates and real time monitoring.