Shipowners can find more efficiency and reduced emissions from their two-stroke engines by applying the latest turbocharging technology
Tankers and bulk carrier tonnage will have to shoulder most of the added pressure stemming from the introduction of the IMO Energy Efficiency Index for Existing Ships (EEXI) and the as-yet undefined Carbon Intensity Index (CII), according to Oliver Riemenschneider, president of ABB Turbocharging.
Speaking to Marine Propulsion, Mr Riemenschneider explained that tankers and bulk carriers will be the most challenged of all vessel types by the new regulations because they operate at the highest speeds of comparison maximum continuous rating (MCR). EEXI limits the amount of CO2 emitted per unit of transport supply. Both regulations would be implemented by 2023 to support IMO’s 2030 carbon intensity targets.
Looking at the container shipping sector, Mr Riemenschneider said container ships would be less exposed to the index-driven requests to be more carbon efficient, given that they are already slow steaming on their routes.
To support shipping’s efficiency and CO2 reduction ambitions, ABB Turbocharging has developed a number of upgrade options and products, some co-developed with the OEMs. “In recent months, we have seen a real interest and received a number of requests from shipowners on increasing the efficiency of the engine, reducing emissions and applying the latest turbocharging technology to installed engines,” said Mr Riemenschneider.
In one interesting case, ABB Turbocharging worked with Norwegian tanker owner Odfjell; Mr Riemenschneider explained that ABB Turbocharging looked at the whole engine setup to provide Odfjell with an opportunity to optimise the engine to meet new power demands, lower emissions and provide improved fuel consumption.
Initial work was performed on the chemical tanker Bow Sun, changing the design of the ship’s propeller and retuning its engine for low-load optimisation and to meet IMO NOx classification. ABB Turbocharging modified the engine’s shims, exhaust, fuel-cam position, VIT parameters, cylinder liner insulation, and upgraded turbocharger components including the nozzle ring and compressor wheel.
Derating the engine for optimal power with the new propeller, along with engine retuning and turbocharger upgrades for optimal performance, has helped Odfjell save money on operating costs and to reduce emissions. CO2 emissions have been cut by 3%, while NOx is down by 20%, helping Bow Sun to maintain IMO compliance and meet IMO Tier I regulations.
Bow Sun is one of eight Polish vessels in the Odfjell fleet, and the success of the overhauls means Odfjell will continue to partner with ABB Turbocharging over the next few years to upgrade the remaining ships.
Turbochargers and alternative fuels
As part of a wider discussion with MP, Mr Riemenschneider discussed the critical link alternative fuels will play in shipping’s decarbonisation and how the leading marine turbocharger company is supporting the industry’s transition. ABB Turbocharging is working closely with OEMs on the development of engines and components that will underpin shipping’s adoption of low- or zero-carbon alternative fuels.
“With alternative fuels like ammonia or hydrogen, for example, the flame speed in the combustion process is totally different than what we have with today’s fuels,” noted Mr Riemenschneider. “With today’s fuels, like diesel, LNG or even methanol, the flame speeds are pretty similar. However, if you look at ammonia – it burns very, very slowly – while hydrogen is an immediate explosion. This requires different combustion systems and different methods to control the combustion process. This will put different requirements on the turbocharger regarding efficiency and pressure ratio. That’s a real fundamental technology development.”
ABB Turbocharging is working on a development for a two-stroke, dual-fuel, ammonia engine. Plans call for the first such engine to be delivered to shipyards in 2024.
Mr Riemenschneider said ABB Turbocharging can lean on its previous experience with alternative fuels in shoreside applications. For example, a power plant operating in Hamburg has the capability to operate on various mixtures of LNG and hydrogen. “This provides us with a wealth of experience on how to run the engine and combustion process in real operating conditions and with the different blends,” he said.
“We have received a number of requests from shipowners on increasing the efficiency of the engine”
Turbochargers will play a critical role in the transition to cleaner fuels and the overall efficiency of a ship’s engine. ABB Turbocharging is supporting the use of alternative fuels for use in small- and medium-bore, two-stroke diesel and gas engines, too. It introduced two new turbocharger models for smaller engines in response to the implementation of the IMO 2020 0.50% sulphur cap.
“They are the so-called ‘small babies’ of our lineup,” Mr Riemenschneider said. “They bring exactly the same efficiency and pressure ratio we have for our larger designs. The new models are aimed at improving the performance of smaller engines to a level which we have seen only in larger engines.” He said the advantages of the new compact turbochargers are lower capex, lower opex and a smaller footprint.
Scaled down from its proven A100-L and A200-L designs, the new turbocharger models offer a smaller size, incorporating the latest rotor component technologies. Their compact design allows installation flexibility in modern, space-optimised enginerooms.
The A255-L and A260-L turbochargers can be used on low-pressure, dual-fuel engines to optimise combustion, improving engine efficiency and allowing for the reduction of greenhouse gas (GHG) emissions. Providing high turbocharging efficiency, the A255-L and A260-L turbochargers ensure that a high air-fuel ratio is maintained in high-load operation, reducing the tendency for fast combustion which can adversely affect operation and emissions. The A255-L and A260-L turbochargers also facilitate the utilisation of emission-abatement technologies for NOx and SOx reduction.
ABB Turbocharging says that due to the significant efficiencies achieved, the A255-L and A260-L turbochargers can reduce the IMO Energy Efficiency Design Index (EEDI) of smaller cargo vessels in the size range of 10,000 to 40,000 dwt that make use of small- and medium-bore two-stroke engines. These will typically include vessels such as bulk carriers, tankers, container feeders and car carriers.
Data-driven maintenance decisions
For turbocharger maintenance and repair, ABB Turbocharging launched last year its Turbo MarineCare data-enabled service agreement programme to support shipowners operating vessels with two-stroke engine turbochargers. The idea behind the programme, explains Mr Riemenschneider, is to use operational data to understand the exposure of the rotor and make a judgement as to whether it is ‘good to go’ for another period. This allows owners to use real operational data to make condition-based maintenance decisions, instead of fixed interval-based decisions on operational hours.
“We perform data analysis and physical inspection of the rotor,” said Mr Riemenschneider. “Based on this, we provide a warranty. This provides the owner with the benefit of not being exposed to any unbudgeted or unpredicted costs. That’s the mechanism of the financial side. This offers a flat fee for the overhaul. Anything that happens between drydocks, we take the risk,” he said.
There has been strong interest in the market, with a number of vessels running under the plan, according to Mr Riemenschneider.
In the case of implementing the Turbo MarineCare programme for older vessels, the data quality has to be built up to create an operational history. “We work with owners on identifying the right sources and cleaning the data sets to create a ‘pocket picture’ of what the operation was like, in order to make the right judgements on the material properties based on our experiences and the data we have,” explained Mr Riemenschneider.
“What’s interesting now,” he said, “is that owners looking at newbuilds are interested in doing it from the hour zero. We can then cover two dry docks as the engine and the turbocharger are young.” This provides quality data from the beginning of the vessel’s life.
When the physical inspection is performed, ABB Turbocharging technicians will use handheld devices to record data and take images to collect information to make a sound judgement on the condition of the turbocharger. Additionally, this provides evidence to the owner of the condition of the product if there are any questions from class or an insurer.
Mr Riemenschneider said the data from the Turbo MarineCare programme is aggregated and anonymised. The owner of the data is the customer. The data is used by ABB Turbocharging in order to improve the product and improve its offerings to the customer.
“Sharing data is to the immediate benefit of the respective customer. That’s a general trend across industries and we are just beginning to see [it] in the marine industry,” he said.
“New regulations on emissions, CII, on the operational reporting will support the use and implementation of more digital-based functionalities onboard and shared with shore, so that we have this seamless information and accurate decision-making,” he said.
Digital tool usage increases
As is increasingly the case, digital tools are being implemented in the marine industry to improve efficiency, provide more transparency and insight and to lower operational and maintenance costs. “Covid is driving digital interaction with customers,” said Mr Riemenschneider. “There is much more awareness and readiness to use digital tools in the marine environment with regard to maintenance.”
Using a new app developed by ABB Turbocharging, the crew can use a handheld device to receive maintenance and repair instructions on how to disassemble a product and make judgements on whether to use, reuse or replace parts based on measurements.
“With alternative fuels the flame speed in the combustion process is totally different than what we have with today’s fuels”
“This is a hands-on support of the operator,” noted Mr Riemenschneider. “This helps the operator make a sound judgement and also identify exactly what part is needed. This avoids ‘hiccups’ in identifying or ordering wrong parts. That is a seamless connection from the product installed to what part is needed. This can then be communicated to the purchasing department, which requires higher quality and accuracy of what needs to be done in a repair,” he said.
This service is being tested on small turbochargers for auxiliary engines, with the first commercial deliveries in 2021.
The future is happening
Additive, or 3D printing, and delivery of spares by drone are coming into use to support ship maintenance and repairs. “Part of the future is happening already,” said Mr Riemenschneider. “We are seeing parts delivered by drones. We have started using – not in a lab, but in manufacturing – 3D printing for a few component ranges. These parts have a high variance. At the end of the day, it is more cost efficient and it is also [better] from the perspective of ESG. You have a circular economy, where you try to make best use of materials, or reduce the use of materials as much as possible” he said.
This goes hand-in-hand with giving digital tools to the crew to support maintenance and repair decisions onboard, providing error-free data transfer to shoreside purchasing personnel. “You can really deliver what is needed and you avoid expensive spare parts docking and stocking levels. This will also provide efficiencies in transactions, making them more direct and less time consuming,” he pointed out.
Mr Riemenschneider sees alternatives fuels as the continuing ‘big topic’ and a big challenge for the industry, as they must be viable both from a technical and commercial standpoint. “If you look at a big container ship carrying goods from Shanghai to Europe, it emits about 9,000 tonnes of CO2e. If you value that CO2 at US$60 to US$70 per tonne – which is what it is being paid in Europe – then you end up with about half a million dollars surcharge on CO2 emissions for that journey. However, if you look at the value of the entire load … it means you might pay six cents more for a pair of jeans. I think this industry is really in a spotlight and has a huge change in front of it. The impact for the larger society, commercially, is absolutely digestible. It’s a very difficult transformation, but somehow, we have to find a decent way, supported by good regulations, to drive this.”
He also feels in order to achieve true sustainability, shipping stakeholders much look at emissions in a holistic manner.
“There’s a discussion whether well-to-wake or tank-to-wake (emissions) is the right approach. We are of the opinion that well-to-wake is the comprehensive view. For example, if a battery (used on ship) is charged on land, that’s a positive impact for the operational index. However, it really depends on what is the CO2 footprint of electricity. In some countries in Europe, electricity has a larger CO2 footprint than when you run on a diesel engine. We need to take a broader view. If people want to drive sustainability long term, it needs to be steered by the right regulation,” concluded Mr Riemenschneider.
Based in Baden, Switzerland, Mr Riemenschneider was appointed president, ABB Turbocharging in 2011, previously serving as senior vice president sales and marketing and member of the executive board since 2003. He joined ABB Turbo Systems AG in 1991 and has worked both in Baden and Japan, including periods as director and vice president of ABB KK, Tokyo, senior vice president of Turbo Systems United Co, Ltd, a joint venture between ABB and Japanese turbocharger specialist IHI, and manager of the Turbocharger Division at ABB Industry KK, Kobe, Japan.
He holds a Master’s Degree in Mechanical Engineering from the Swiss Federal Institute of Technology, Zurich, and an MBA from the Zürich Campus of the City University, Bellevue, Washington.