MAY 3, 2016 — Wind power could play a role as a power source in offshore oil and gas operations. For the past year, participants from both the renewable and oil and gas industries have been cooperating in a joint industry project led by DNV GL to develop the concept of using floating wind turbines to power a water injection system and assess its technical and commercial feasibility.
The WIN WIN (Wind powered Water Injection) project has been looking at a use case involving a system located in the North Sea, 30 km from the production host and 30 km from shore, at 200 m water depth. The reservoir consists of two injection wells, with normal injectivity, and a target injection rate of 44 000 barrels of water per day.
The system specified features a 6 MW wind turbine mounted on a spar foundation, with two 2 MW injection pumps, capable of a maximum of 80,000 barrels of water per day. The process equipment is located top-side. Water treatment includes filtration and chemical injection with chlorine.
The JIP partners include ExxonMobil, ENI Norge, Nexen Petroleum UK Ltd., Statoil, VNG Norge, PG Flow Solutions and ORE Catapult.
DNV GL says that the JIP study has identified no major challenges. Analyses of system performance examining site specific cases from JIP partners have shown that WIN WIN is able to meet key performance requirements such as injection volume targets, as well as reliability and minimized downtime.
"For the first time we can now see renewable energy as a large scale source of power to offshore oil & gas operation,s" says Remi Eriksen, Group President and CEO of DNV GL. "By utilizing the recent developments of floating offshore wind turbines this concept can offer a clean, reliable, and cost effective alternative for powering water injection in offshore locations."
"We are encouraged by recent advances in wind technology, particularly for niche applications such as offshore oil and gas operations," says Sara Ortwein, President of ExxonMobil Upstream Research Company. "Such technological advances improve the economic feasibility for wind to contribute to the overall energy supply mix."
"Supplying clean power to oil & gas installations was part of the original idea behind Statoil's Hywind concept", says Hanne Wigum, Head of Renewable Technology Development in Statoil. "The WIN WIN concept represents an alternative source of electricity and has the potential to open up new opportunities for field development."
The costs for wind powered water injection have been compared with a conventional alternative where water is injected via a flow line from the host platform. While the WIN WIN technology has higher operational expenditures (OPEX) compared to a conventional alternative, the significantly lower capital expenditure (CAPEX) means that it compares favourably over the long term. WIN WIN is therefore seen as a commercially competitive alternative in a range of cases, particularly when host platform capacity is limited or injection wells are located far away.
"For the specific example case assessed in the report, we are looking at a potential cost saving of approximately 20 percent compared to a conventional solution. This will of course vary greatly between cases, " says Johan Sandberg, project sponsor and segment leader of floating wind turbines at DNV GL. "To develop the concept further, a next step would be to test critical subsystems in a small scale physical set-up. The key objective would be to gain assurance that the components integrated in this configuration will offer satisfactory performance over time with a variable power input. A potential phase 2 of the JIP is being explored with some of the current JIP partners."