Offshore wind capacity around the world is exploding in size as different territories set stringent renewable energy goals. 

It is a core part of the European Green Deal, and investment is increasing massively. Forecasts suggest the EU needs to build an average of 30GW a year to meet its 2030 targets, which is placing a great deal of pressure not only on manufacturing facilities and supply chains, but  on available assets needed to maintain and repair this capacity.

Peter Burger

Peter Burger, global director Sustainability with Fugro

This Operations and Maintenance (O&M) phase of a wind farm’s lifecycle – typically around 25-30 years – relies a great deal on marine logistics between the shore and the wind farm. Currently, most of these vessels are using marine diesel, with an accompanying carbon emissions impact. As projects have tended to become larger and further offshore, combined with pressures to reduce operating expenditure, we have seen a tendency for larger vessels.

These can operate in a wider array of weather conditions, provide optimal cargo capacity, and are powerful enough to spend minimal time in transit. When you consider the number of vessels in operation to maintain the hundreds of offshore wind farm sites across Europe, the choices that are made here have a huge impact. Everything from the fuel sources, hull and propeller designs, to operating timetables and behaviours all play their part.

Practical and scalable solutions

Of course, marine vessels aren’t only used in wind farm deployments – everything from sea defences, port infrastructure, wave and tidal energy projects, and all manner of other offshore infrastructure rely on regular marine vessel access for maintenance. During the O&M phase – the longest part of a typical offshore wind project – service operation vessels (SOVs) are deployed, meaning that decarbonisation of these vessels specifically is likely to have the greatest impact in accelerating to a clean maritime future.

Methanol is a product that has already been used as a marine fuel source for a number of years. Transported as cargo in maritime environments for decades, it is essential in the production of many kinds of plastic packaging, paints, coatings and building materials. Green methanol offers CO2 emissions reductions of as much as 95% compared to traditional marine fuel, depending on how it is produced. Methanol-fuelled ships have been in operation for several years in select contexts, and availability of the fuel at ports is increasing. Converting vessels to run on methanol is also more of a straightforward process than for the likes of LPG fuelling.

Industry collaboration

Fugro is leading a maritime consortium on a programme called MENENS (Methanol as an Energy Step Towards Zero-Emission Dutch Shipping, abbreviated from the Dutch), which is working on making methanol a commercially deployable, low-carbon marine fuel.

Fugro Pioneer 02

Fugro Pioneer 

This isn’t just about fuelling the engines – aspects like ensuring a ship’s electrical system can handle changes in engine performance, storing the fuel safely onboard, as well as the lower energy content per volume of the fuel itself, must be considered. Operational safety is clearly of paramount importance and compared to alternatives such as LNG, hydrogen and ammonia, methanol poses the least overall risk. In time, it is the aim of the Dutch maritime masterplan to have 30 zero-emission ships in operation by 2030, and at Fugro we are aiming for our Fugro Pioneer survey vessel to be sailing on methanol by 2024.

It is likely to be the less complex vessels in terms of engine and fuel systems that will initially lead the way with practical use cases, before solutions become more scalable. Vessels also have a long lifetime, with those being commissioned today having the potential to be operational well beyond 2030. Operators therefore need a detailed retrofit programme in place, both for current fleet and for vessels being designed today so they are retrofit-ready for the future.

For certain use cases, traditional crewed vessels can be removed entirely from deployment. Advances in connectivity and technology are making autonomous and remote inspection projects a reality, made possible by uncrewed surface vessels controlled remotely. They are not only safe because they don’t need crew, they also have significantly reduced fuel needs.

It will take a combination of clean technology in newbuild vessels and retrofitting, alongside infrastructure portside and more remote operations to make full decarbonisation a reality. No single option will likely provide a complete solution, and industry and governments alike need to keep an open mind to all possible solutions. As standards are developed and commercially viable frameworks become clearer, the next few years look set to be exciting.