There are a number of ways vessel managers can reduce the impact their fleet has on the environment. Better vessel behaviour, sustainable fuels and electrification upgrades can all help reduce emissions.
Spinergie’s Enviro Score system aims to provide a clear indicator of which vessels have the best performance in terms of emission reductions. Marked out of 100, the enviro score calculation is based on both the emission reduction technologies on board as well as behaviour analysis of the vessel, taking into account overspeeding for example.
Here, Spinergie examines the impact enviro upgrades have already had within the fleet, how Spinergie’s enviro score provides a strong market indicator, and developments are next on the horizon.
Key emission reduction technologies
The most mature emission reduction technology upgrades in place within the fleet today are Energy Storage Systems (ESS) and Shore Power.
ESS is the presence of a battery system on board the vessel which will improve fuel efficiency in operations with power load variabilities such as DP or transit in rough conditions by peak shaving and load levelling. It can also be used for spinning reserve and battery backup power. While exact levels of fuel saving vary, the industry estimates that having an ESS on board saves approximately 15-20% on average.
The inclusion of shore power capabilities on board a vessel allows for the diesel engine to shut down while the vessel is in port and connected to the main onshore power grid. Spinergie estimates that shore power connection reduces fuel consumption by around 10%.
A clear link between high enviro score and high utilization in the PSV fleet
There are currently 73 Platform Supply Vessels (PSVs) in the global fleet equipped with an ESS including the 61 PSV conversions which have been recorded since 2016. The use of hybrid batteries/energy storage systems is proven to be an effective solution within the PSV sector. In addition, Spinergie analysts have observed a strong correlation between vessels with high enviro scores - being equipped with ESS brings vessels to an enviro score of 75 on average - and high utilization.
High utilization is particularly clear to see in the North Sea. Overall, ESS-equipped PSVs in the region have had an average utilization rate of 85% since 2020, compared to an average 63% for non-ESS-equipped PSVs. With ESS impacting overall utilization by up to 20%, this correlates to an increase of 72 working days over the course of a year which in turn increases revenue.
Tidewater boosts its ESS-equipped PSVs
In March, it was announced that Tidewater had purchased Solstad’s entire fleet of 37 PSVs and its entire ESS-equipped fleet. This strategy has also made Tidewater the foremost global player in ESS-equipped PSVs. With 13 such vessels in total (from the Solstad fleet acquisition) - it is highly likely the market will see its utilization numbers increase in line with the general trend as previously witnessed with Solstad frequently hitting 100% PSV utilization since the ESS-upgrades of its fleet in 2021.
Upcoming developments in emission reduction technologies
ESS is currently the most mature emission reduction technologies, mainly due to its relatively easy implementation meaning there is no need for long vessel immobilization. Looking forward, however, there are a number of emerging technologies which are predicted to have an impact in the near future. Most notable are the new low-emission fuels under development which the use of will also have a positive impact on a vessel’s enviro score.
The three main fuels to watch are Hydrogen, Methanol and Ammonia. Compared to conventional Marine Gasoil (MGO), these three fuels can reduce Well-to-Wake (WtW) emissions by up to 90% if produced by renewables. Moving forward, the industry will need to heavily rely on these new fuels in order to achieve net-zero targets and drastically reduce emissions. Already, some offshore vessels are using these new fuels in testing and development including Fortescue Future Industries’ (FFI) Green Power, the first PSV with ammonia notation, which has just finished conversion in Singapore and will soon be ready for operations.
In the interim, however, global fuel supply chains are not yet mature enough to supply large quantities of these fuels and costs are prohibitively high. As it stands, greenhouse gas emissions from alternative fuels are highly correlated with the processes in place to produce the fuel. Therefore, in the short-term, emission reduction from fuels will rely on multiple different types of fuel being used.
In essence, in order to continue improving enviro scores and reducing emissions, the industry cannot solely rely on either the inclusion of emission-reduction technology or new fuels. Both will be required to tackle the challenges of reducing carbon footprints while vessel managers also ensure their fleets maintain high utilization. Spinergie’s enviro score makes it clear that these factors, in combination with reducing vessel speeds, having better energy management systems in place, and improving vessel design, are all key to matching net-zero challenges.
Contact Spinergie today for a demo to discover how our dynamic Enviro Score tracks the efficiency of offshore vessels in reducing air emissions while operating.
