Ardmore’s choice of vessel performance technologies

Ardmore Shipping is implementing and trialling a wide range of technologies to improve vessel performance, some not discussed much before, such as ultrasonic cleaning and microboilers.

They gave us an update

Product / chemical tanker operator Ardmore Shipping, based in Cork, Ireland, is using and trialling a number of interesting performance technologies. Ardmore assessed over one hundred technologies during 2022 – and is trialling or fully implementing twelve of them.

Garry Noonan, Director, Innovation at Ardmore, and a former marine engineer onboard vessels with BP Shipping, told us what the company is doing.

Ardmore is exploring using ultrasonics for cleaning propellers, hulls, and speed logs; very low load boilers; and microboilers. It is using or trialling automation to keep the vessel at constant power; variable speed drives; propeller boss cap fins; more frequent speed optimisations; harvesting rainwater; and super-smooth coatings.

Ardmore is also pursuing a unique approach to shipboard carbon capture, where the CO2 rich solvent is kept onboard and separated onshore.

Ardmore takes its ESG (environmental, social and governance) responsibilities so seriously it has created a sustainability committee within its board of directors.

It is chaired by Dr Kirsi Tikka, a former senior executive with the American Bureau of Shipping. The other members are Mats Berglund, former chief executive of Hong Kong bulker operator Pacific Basin, and Helen Tveitan de Jong, CEO of Carisbrooke Shipping Holdings, an operator of thirty-four bulk and project cargo ships.

Ultrasonic cleaning

Ardmore is trialling ultrasonic propeller cleaning. This means using a very high­pitched noise or ‘ultrasound,’ which agitates a material, leading to a cleaning effect, such as particles being shaken off.

It is experimenting with ultrasound around the propeller, which may help prevent a build-up of microfouling on the propeller.

It is exploring the use of ultrasound around the sea chest (where a vessel takes in sea water), to see if it can help prevent fouling taking place. Some countries have regulations requiring sea chests to be kept clean because they are concerned about microbes in fouling being moved around the world.

Ardmore is looking at using ultrasound to try to keep speed log sensors clean. This has an indirect impact on vessel performance, in that accurate speed log measurements are very important in assessing vessel performance. Fouling on the speed log can impact the accuracy of the readings.

With ultrasonics, it is possible to experiment with different frequency sounds, to try to find the frequency which is most effective at stopping the fouling. You may need a diver to visually inspect if it is working.

Low load boilers

Ardmore is looking at ways to run boilers at 5 per cent of maximum load. So far, it has only been possible to run boilers at 20 per cent of maximum load. “We’ve approached boiler manufacturers to see if we can get that down further,” he said.
Currently, if the vessel requires much less steam than a boiler at 20 per cent load produces, the boiler is continually switched on and off. But every time the boiler switches off there is a need to blow cold air through the furnace to make sure there are no products of combustion left in the combustion chamber. So, running continuously at a lower load would be more efficient, Mr Noonan says.
Ardmore is exploring the use of compact marine boilers or “economizers,” which generate steam using waste heat from auxiliary engines when the vessel is stationary. One example is the Alfa Laval Aalborg Micro.

This means that, while the main engine is not running, the micro boiler can supplement the boiler hence reducing the boilers fuel consumption. When the main engine is running, surplus heat from the main engine can generate the required steam.

Ardmore anticipates fuel savings of one tonne to 1.5 tonnes of fuel a day from using microboilers.

Ideally, every generator on a ship could have an associated compact boiler, but there is not enough space. “It is only realistic for one,” he said.

The compact boilers are being installed on Ardmore vessels during dry docks. By the end of Q4 2024, they should be installed on nine vessels, Mr Noonan says.

Constant power

Ardmore implemented Manta Marine’s “FuelOpt” propulsion optimisation technology across its entire fleet during 2023. This is an automation system which keeps the engine operating at a constant power. This means that the fuel supply to the engine does not fluctuate, and the engine is continuously doing the same amount of ‘work,’ which means it is more efficient.

Most engine and propulsion control systems are designed to keep the vessel operating at a constant RPM, like a car always at 70 kilometres per hour. But this means the work done by the engine is always going up and down.
For example, the engine will do more work to keep the vessel at a constant speed if the vessel suddenly faces a strong wind, just as a car engine works harder to get seventy kph speed when going up a hill.

Fuel savings of typically 1-2 per cent over the voyage are typically possible by maintaining constant power, without the voyage taking any longer overall, Mr Noonan says. A computer model of a voyage showed “conservatively” a saving of 2 per cent. So,a small saving, but one achieved at very low cost.

Of course, it is possible to keep an engine at constant power manually, by keeping your eye on the engine power meter. But this requires mental focus and attention, doing a task which can easily be done by machine.

Variable speed drives

Another useful technology is the “variable speed drive,” a system for adjusting the frequency of electricity supplied to rotating equipment such as a pump. In doing so, it can slow the rotating equipment down, and reduce its power consumption.

Much rotating equipment does not have adjustable speed, just an on-off control. Ships are designed with higher power than they need most of the time in case they ever need the full power. But this means they are wasting energy the rest of the time.

It is hard to specify the savings from this because it depends on the environmental conditions the vessel is operating in.

A specific example of where savings can be achieved is on power for the seawater pumps which bring in water to cool the engine. When the vessel is operating in a cold climate, less cooling water is needed, so the pump does not need to run at the same power. There can be savings of “on average a tonne of fuel a day,” he says.

Similarly, less power may be needed at different times of year for engine room fans and air handling units for accommodation.

Propeller fins
Ardmore has installed propeller boss cap fins on the propellers of many of its vessels. This is a physical device which reduces hub vortexes on the propeller and has been proven to lead to worthwhile efficiency savings.

“We would also roll this out across any new vessels we bring into the fleet,” he said.
More frequent speed optimisations
Ardmore is making more frequent optimisations of vessel speed, working together with a company called Deepsea Technologies (

Normally, speed is only adjusted daily. This software generates recommendations on the optimal speed for every 10 minutes of the voyage.

The system takes multiple factors into account, such as the cost of the ship per day when a slower speed makes a voyage longer. If freight rates go up, it makes financial sense to go faster. It also considers the changing cost of bunker fuels. “This is not a revolutionary idea, it is more an evolutionary idea,” he said.

Previously the work was done using Excel, which is labour intensive. “It is about trying to find that optimisation without us doing massive calculations,” he said.


Ardmore is harvesting rainwater for cargo tank washing. If seawater cannot be used to wash the tanks, the ship needs to desalinate water onboard, or purchase water in a port, which all involve more energy and costs.

There are already systems to channel rainwater which falls on the vessel’s accommodation area and send it to drains. Instead, it can be sent to tanks.

“We’re taking rainwater which falls on the vessel, filtering it, and testing it,” he said.



Ardmore is exploring new hull coatings, which are “ultra smooth,” so low friction and very hard for anything to stick to. And because the surface is hard, it is not damaged by cleaning. Conventional anti-fouling coatings are degraded every time they are cleaned, so you might not clean them as often as you would like to for fuel efficiency reasons.

It is looking at a coating called Seacoat which provides this (see separate article).
It is also looking at graphene coating on the propeller, which provides a very smooth, hard wearing surface coating.

Shipboard carbon capture

Ardmore believes shipboard carbon capture, removing CO2 from the ship exhaust and storing it onboard, will be a “prominent part of the energy transition going forward,” he said.

Ardmore’s proposed carbon capture system is different to systems used on land. On land, there are two stages, one where the CO2 is dissolved into an amine solvent, and a second stage, where CO2 is separated from the solvent by heating it, so the solvent can be re-used, and CO2 sent to be sequestered.

Ardmore’s proposed maritime system would only include the first stage, and then store the CO2 rich amine liquid in a tank onboard. The second stage, separating the CO2 from the amine, would then take place on land. This means that the ship does not have to provide the necessary heating to separate CO2 from the amine, or to handle CO2 in gaseous form.

One of the vessel’s tanks would need to be converted to store the amine solvent. This does not require any heating or pressure. “It’s not a massive upgrade - we could do that at sea or in water,” he says.
Ardmore is currently seeking a partner who is interested in developing the necessary infrastructure and systems, he said.

One challenge is that there would need to be a worldwide network of reception facilities for CO2 rich amine. Ardmore’s vessels operate on the spot market, rather than trading the same route all the time, and so it would be very hard to have a reception facility in every terminal a vessel might be using.

How to manage it

To manage and make decisions about all these energy saving measures, Ardmore has a team of staff dedicated to the energy transition drawn from other areas of the company, including legal, commercial, technical, and “everything in between.”

People from different backgrounds bring different perspectives. “We don’t want [only] 10 engineers sitting in the room,” he said.
“It is easy to throw technologies [onboard]. But we need to be conscious when it is enough. If you throw too much at them, stuff starts getting missed.”

There can be a preference for ‘passive’ technologies, which can be operated on ships without the active involvement of crew.

One example is autonomous robots for hull cleaning. “ If we have a resident robot we can clean whenever the vessel is stationary,” he said.




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