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WAPS

retrofitted with larger systems that may obstruct tion as a proxy. According to IEA stats, each
lines of sight, then the use of cameras and sen- tonne of steel emits 1.4t CO2 during production.
sors will enable these systems to be deployed Though the weight of wind propulsion systems
safely. If a ship has a hybrid diesel-electric drive varies, if we estimate that a fairly large-sized
train, then this may also afford more control over wind propulsion system weighs 200t (including
engine efficiency, as adjustments to the variable the foundation), then the total CO2 emissions
amount of wind energy delivered to the vessel from the production of that system are 280t
can be made more readily. EMS developers are CO2, along with a small amount from the trans-
increasingly taking wind propulsion into account port and installation at the yard. On the other
in standard direct propulsion systems. hand, the system delivers 10% of the propul-
sive energy required for a ship burning 5,000t
❺ Does wind-assisted propulsion have an VLSFO per year. Therefore, it reduces fuel con-
expiration date? Once the fuel indus- sumption by 500t per year, which corresponds
try achieves large-scale production and to decreasing emissions by 1,550t CO2 per year.
widespread distribution of zero-emis- Thus, in this case, the WAPS would offset the
sion fuels, will wind-assisted propulsion carbon emissions from its construction in
become obsolete once again? roughly two months.
The short answer is no. The longer answer covers
the three main aspects of wind propulsion. ❼ Wind-assisted propulsion benefits
Firstly, in terms of emissions, we need to remem- largely depend on a vessel’s route.
ber that wind propulsion energy is the only energy Therefore, in theory, they are a great
source that has absolute zero emissions, meaning fit for vessels involved in liner ship-
neither carbon emissions (GHG) nor black car- ping (e.g., containerships, vehicle
bon, particulate matter, VOCs, fugitive hydrogen, carriers, and large-sized bulk carriers
underwater radiated noise, etc. It generates no and tankers that call on specific ports)
well-to-tank emissions and has a very low tank- or for vessels chartered on long-term
to-wake impact from the systems themselves. contracts dictating their routing.
Therefore, as regulations for these other emis- However, the bulk carrier and tanker
sions are enacted, the incorporation of wind pro- spot markets are volatile regarding
pulsion will help reduce exposure. the vessels’ destination and routing.
Secondly, regarding economics, using a zero-cost Will this prove to be a challenge for
energy source that is already competitive with fos- the adoption of wind-assisted pro-
sil fuels means that replacement fuels will need pulsion?
to be even cheaper than existing fuels in order There are a lot of variables at work when it
to make wind power redundant. Currently, huge comes to getting the most out of wind instal-
subsidies (direct and indirect) and costs are exter- lations, and routing is certainly a critical one.
nalised in fossil fuel provision and this approach While predicting long-term benefits for liner
is being mirrored in the new, alternative fuel mar- services will be easier, the available routing
kets. Thus, wind will remain competitive unless we software along with machine learning advances
choose to subsidise other energy options. means that hundreds of routing simulations can
Thirdly, wind propulsion provides resilience in be made in a matter of hours to maximise the
several ways. There is no price volatility and no benefits for vessels operating in tramp shipping.
supply issues in port. At the same time, wind is Of course, certain routes will offer better wind
resilient against new emissions regulations. A conditions at different times of the year, but
wind-installed vessel is a hybrid by nature, pro- most operational profiles will still deliver signif-
viding redundancy with an additional propulsion icant wind energy contributions when averaged
system. Finally, it is a range extender, allowing lon- over a year of operation. Thus, we do not view
ger routes to be completed with far less fuel or this as a substantial issue for the further uptake
increasing the vessel’s options for bunkering ports. of the systems.
Additionally, a future alternative could involve
❻ Focusing solely on environmental deploying a modular system or moving a sys-
impact, how long does it typically take tem from one ship to another that will operate
for a WAPS to offset the carbon emis- on a more favourable route. Once a foundation
sions released during its construction? has been installed, the actual rig can be fitted
This varies depending on the size of the system, or removed in a few hours to a day. This is not
the materials used in construction, etc. However, a common practice as yet, but it is certainly a
we do a simple calculation using steel construc- feasible option.

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