One company with a healthy track record of using data and analytics to its advantage is Solstad Offshore ASA, which has utilised a software platform developed by Yxney Maritime to reduce fuel consumption and emissions over the course of the last few years.
As Solstad Offshore showed at April’s Middle East Offshore Support Journal conference in Dubai, there are prospects for robust future growth in digitalising the Offshore Support Vessel (OSV) fleet, using big data and analytics to optimize fleet operations.
Having begun its Solstad Green Operations programme in 2009, Solstad Offshore has some 10 years of experience in working with its clients to reduce emissions and save on fuel costs. However, when a recent merger saw the company’s fleet more than quadruple in size, Solstad was faced with the challenge of continuing to effectively manage its fleetwide energy consumption while not adding to its administrative costs onshore.
The solution, for Solstad, has been to implement Yxney´s Maress software. Presenting on the initiative, Solstad showed that the company has seen fuel savings of 18% fuel across its fleet of 147 OSVs by focussing on efficiency improvements. In 2018 alone, the project reduced CO2 emissions by almost 20,000 tons, according to Svein Erik Isaksen, Health Safety Environment Quality engineer at Solstad.
A key component of the programme is optimising propulsion and Dynamic Positioning (DP) operations to reduce fuel savings.
Monitoring fuel efficiency measures in an offshore fleet can be challenging due to the complexity of operations and operational patterns vessels undertake. To account for the variable conditions, the Maress software creates a historic baseline for all the operational modes of each vessel, according to Mr Isaksen. A vessel’s performance is compared against the baseline, which is adjusted for the actual operational pattern in order to identify deviations and sub-optimal operations.
Initially, data from 13 vessels was analysed to identify the fuel efficiency of the vessels in various operation modes. The analysis was used as a foundation to come up with new fuel saving initiatives, which Solstad calls Solstad Green Operations (SGOs), where 1 SGO equals 500 litres or 0.5 m3 of saved fuel. Some of the new SGO benchmarks identified with Yxney’s Maress software include more efficient operational methods of waiting out poor weather conditions; more efficient thruster biasing in calm weather; and lean initiatives such as actively coordinating with clients for best speeds.
No additional hardware or software were installed in the vessels as part of the project, says Yxney Maritime CEO Gjord Simen Sanna, but each vessel has a dedicated person responsible for finding SGOs.
Close coordination between the crew and the data development team helps to facilitate these data-driven decisions to save fuel and emissions, according to Mr Isaksen. Inferences from the data are shared with the crew of the vessels, regularly, helping them come up with operational measures that will cut fuel usage.
Mr Isaksen explains in detail some of the changes in vessel operation have come as a direct result of inputs from data analytics. The following are some of the measures that vessel crews have come up with to reduce fuel consumption:
Onboard Normand Naley, which has four main engines, the crew, while waiting for bad weather to turn calmer, run only one main engine and one aft thruster. The DP system is activated to control the vessel’s heading to keep it against the wind. In sway, the vessel is allowed to move sideways, but this outcome is limited by the DP’s heading control. When the vessel is in surge, the joystick is used in environmental compensation mode to maintain a steady rate. This allows the engine to work under constant load, eliminating peaks that demand high fuel consumption and increase noise and vibration.
In layman’s terms, the vessel’s hull is riding the waves, rather than pushing against them to stay in the same position. During this wait on weather (WOW) operational mode, fuel consumption is minimized. And there is also a benefit to crew from these operations. It is more comfortable for the crew when the vessel is allowed to move aft and fore with waves.
Other sea conditions in which it is challenging to operate include when weather forces (wind and waves) are acting from several directions simultaneously, as Mr Isaksen explains. Examples include different wave layers acting on the vessel from multiple directions or sea currents flowing perpendicular to predominant wind direction. Of course, these environmental forces are not constant, but regularly shifting and difficult to predict.
Typically, when crews work to counteract the multidirectional nature of these shifting forces, thrusters are pressed into service and the engine power curves fluctuate. To create a more efficient power usage in these conditions, the crew of Normand Naley set up the aft thrusters in biasing mode, 45 degrees outwards from aft on their respective sides. The thrusters are not ramped up, taking only a small load to keep the force constant. This operational setting allows the engines to operate with smoother power curves and higher efficiency. And for sway movements, no time is spent waiting for the thruster to start rotating and ramp up. The vessel can be instantly moved in the direction desired by stopping the thruster on the opposite side.
These types of joint endeavours between data monitors and crew are proving valuable for Solstad clients. Fuel consumption is being reduced, and operations such as biasing typically improve the vessel’s reaction time and safety in bad weather. And, as Yxney Maritime CEO Mr Sanna explains, a focus on efficiency can not only bring down operational costs but can also facilitate chartering for OSV owners.
“During the chartering process, shipowners today have to demonstrate that their vessel is being operated in the most efficient way possible,” he says, leaving clear the implication that dedicated software and careful monitoring of operational data and manoeuvring are the basis for that demonstration.
Solstad’s energy efficiency projects have been partly financed by the Norwegian Ministry of Climate and Environment. On the Yxney Maritime project, Solstad worked with Enova SF, whose mandate is to reduce greenhouse gas emissions and develop technology to combat and cope with climate change.