Service vessel operations in offshore wind farms account today for around 15 – 20 pct. of the GHG-emissions during the life cycle of an offshore wind farm.

The GHG-emissions are due to the use of fossil fuels – typically marine gas oils – for the vessel operations throughout the life span of 25+ years for an offshore wind farm. 

GHG-regulation is tightening in the shipping sector with the latest developments in IMO as well as EU ETS/UK ETS and FuelEU regulation. Being dependent on fossil fuels creates therefore a clear risk of increased cost of fuels to the extent that international GHG-regulation increases the costs of burning fossil fuels. This regulatory cost comes on top of the geopolitical risk of fossil fuel supplies and prices.  In addition to GHG-emissions, vessels burning fossil fuels will also emit SOx, NOx and other particles which directly impacts sea life and if close to shore, the coastal communities as well. 

Stillstrom has developed an end-to-end offshore charging solution, that will enable charging of battery-powered vessels – like service operation vessels – using the wind farm’s production of renewable electricity. 

The Stillstrom Offshore eCharger is a 6 MW charger which will allow a battery powered SOV (E-SOV) with e.g. 25 MWh battery capacity to charge from 20 – 90 pct. in 4-hour incl. connection and de-connection. Charged to 90 pct. the E-SOV will be able to operate for 18 – 19 hours in the offshore wind farm fully on batteries and thereby removing the need for fossil fuels or other fuels for standard operations in the offshore wind farm. 

Direct electrification of service vessel operations in offshore wind farms will itself contribute to: 

• Remove the daily need for 4 – 5 tons of marine gas oil 
• Reduce the offshore wind farm’s life cycle GHG-emissions with 15 – 20 pct. 
• Cost savings on fuel 
• Minimising the regulatory risk of increasing GHG-emission costs through mechanisms like IMO, EU ETS/UK ETS and FuelEU 
• Minimising geopolitical risks impacting global supplies of and prices for fossil fuels 
• Lowering energy import costs for energy import dependent countries by using domestic energy sources 
• Positive impact on marine and sea life as well as the crew due to no emissions as well as lower noise/vibration levels when the vessel is operating on batteries