Decarbonizing the global container fleet with heatpower

As capacity grows year-on-year, the race is on to decarbonize the global container fleet. Container shipping remains one of the most cost-effective and environmentally friendly ways to transport goods internationally, but the advent of emissions charges and penalties, in conjunction with a possible ‘carbon tax’, could send prices soaring. 

To mitigate increasing operational costs, operators need to drastically reduce their environmental footprint. Lowering maritime emissions is often seen as cost-intensive, but this isn’t necessarily true. By integrating the right mix of emissions reduction technologies, shipping companies can maximize their ROI and limit carbon tax liabilities, thus offsetting the costs associated with decarbonizing their fleet.

Cost-efficient and effective decarbonization of the shipping industry depends not on integrating as much on-board sustainable tech as possible, nor on relying on a single form of emissions reduction. Instead, operators must assess the impact that sustainable on-board technologies can have based on the type and operational profile of their fleet.  

Here, we examine the applicability of low temperature Organic Rankine Cycle (ORC) waste heat recovery for container shipping and highlight why this form of emissions reduction can be particularly effective and cost-efficient for this segment of the industry.  

What is low-temp ORC maritime waste heat recovery?

In the maritime industry, waste heat recovery (WHR) refers to the capture and repurposing of the waste heat that is produced via a ship’s engines. With an on-board WHR system, waste heat can be converted into clean electricity and used to fulfil some of the vessel’s energy requirements. 

More than 50% of a marine engine’s energy is typically lost as waste heat and the majority of this heat is produced at relatively low temperatures. An on-board waste heat recovery system ensures this energy is not simply lost but is utilized to maximize efficiency.  

Low-temp ORC waste heat recovery refers to systems operating an Organic Rankine Cycle. An ORC enables lower temperature waste heat to be converted into sustainable electricity and, therefore, enables a higher proportion of waste heat to be repurposed into clean energy.  

Crucially, low-temp ORC WHR enables waste heat from a wider range of on-board heat sources to be repurposed. For example, Climeon’s HeatPower technology can generate carbon-free electricity from waste heat at temperatures as low as 80° C and is capable of generating up to 355kW per unit from engine waste heat.

WHR can be applied to most large vessels in theory, but it is the vessel’s operational profile and usage that determines how productive and cost-efficient an on-board WHR system will be. By analyzing the impact of low-temp ORC WHR in relation to different segments of the maritime industry, we can therefore determine whether the potential emissions reductions and ROI make low-temp ORC WHR a viable and cost-effective method of decarbonization. 

Low-temperature waste heat recovery and container shipping 

While each container ship has a distinct operational profile, the global container fleet consists predominantly of medium to ultra large vessels that spend a large amount of time at sea and have relatively low on-board power requirements.  

This overarching profile makes container ships ideally suited to low-temp ORC WHR. The combination of large marine engines and long sailing times ensure that vast amounts of low temperature waste heat is continually produced, which enables on-board systems, like HeatPower, to generate high clean power outputs,

As container ships have relatively low on-board power requirements compared to other vessels, such as cruise ships, the clean electricity generated via the WHR system accounts for a higher proportion of on-board energy requirements and can, therefore, significantly reduce reliance on fuel-powered auxiliary engines used for electricity production and lower fuel consumption.  

As a result, emissions are reduced, fuel costs are lowered and payback times are minimized, delivering both economic and environmental benefits. To find out how the operational profile of a vessel impacts on-board waste heat recovery and clean energy generation, download Climeon’s White Paper now.  

Reducing Scope 1, 2 and 3 emissions with HeatPower 

Environmental regulations within the maritime sector are becoming more stringent and shipping companies will incur increased expenditure if they fail to reduce emissions. Now that EU’s Emissions Trading System (ETS) is applicable to the maritime industry, for example, container ship operators will need to report emissions generated between EU ports and fund the cost of additional ‘allowances’ if they exceed the relevant ‘CO2 eq’ cap. 

However, this isn’t the only way in which container ship operators are affected by stronger environmental regulation. The increasing focus on Scope 1, 2 and 3 emissions and new reporting requirements mean that customers will require data on the emissions generated via shipping too.  

If a retail company uses 7,500 TEUs on a Very Large Container Ship (VLCS) with a capacity of 15,000 TEUs, for example, it must report a substantial proportion of the emissions generated on the voyage under its Scope 3 emissions disclosure.  

Freight customers will, therefore, select providers that offer low-emission shipping in a bid to minimize their own carbon footprint. For container shipping companies, reducing emissions is not just a critical way to reduce their OPEX; it is essential to remain competitive and retain customers.  

Retrofitting the global container fleet 

Container ship capacity may be experiencing record growth but newbuild ships represent a relatively small proportion of the global container fleet. Although the need for emissions reductions has not come out of the blue, retrofitting some types of sustainable technologies to existing vessels will be complex, costly and time-consuming. 

Selecting emissions reduction tech that is well-suited for retrofit applications is critical to minimize operational disruption and associated costs, and low-temp ORC waste heat recovery can deliver on both counts. 

Featuring a robust, standardized design, Climeon’s HeatPower units can offer a simplified installation process and can be adapted for seamless integration in existing engine rooms.  

In addition to this, Climeon’s HeatPower technology can generate clean, carbon-free electricity from a single heat source, such as jacket cooling water. This further simplifies the integration process and ensures an installation can be completed while the vessel is in dock for routine maintenance.

Maximizing the impact of alternative fuels  

Low-carbon, alternative marine fuels offer a route to decarbonization, but they may not provide an immediate solution to the ongoing climate crisis. Bunkering and production limitations are slowing the uptake of low-carbon fuels, for example, while the increased costs associated with alternatives to HFO may dissuade shipping companies from fully embracing this form of low-emission shipping. 

Despite the challenges, low-carbon fuels are likely to play a significant role in maritime decarbonization. Maritime Insight reports 6% of the 9,600 ships forecast to be delivered in 2024-2028 are expected to feature either methanol or ammonia dual-fuel engines, accounting for 11% of installed engine power.  

Dual-fuel or alternative fuel engines remain viable for newbuild ships, but they won’t be solely responsible for eradicating shipping emissions.   

Instead, shipping companies will need to maximize the effects and offset the increased costs of alternative fuels to hit key net-zero targets and maximize profitability.  

Compatibility with alternative fuels should, therefore, be an important consideration when determining what emissions reduction tech to install, particularly if shipowners want to futureproof their fleet and maximize the ROI of sustainable, on-board technology.  

Climeon’s HeatPower system is not only compatible with alternative marine fuels; it also delivers unique additional benefits when paired with alternative and low-carbon fuels.  

Many marine WHR systems use the engine’s relatively high temperature exhaust gases as a source of waste heat. With most future alternative fuels, steam generated by the exhaust gases is not always needed, for example tank heating. Thus, steam will always be available to such an extent as it is today.  

In contrast, Climeon’s HeatPower technology is capable of generating sustainable electricity without requiring the heat input from exhaust gases. Market-leading conversion efficiency at low temperatures ensures HeatPower can deliver optimal performance using jacket cooling water or HT water as a sole source of waste heat.

Safeguarding international trade with carbon-free container shipping 

The shipping industry has been the cornerstone of worldwide trade for centuries and, over time, it has evolved to encompass the latest innovations and meet the changing needs of society.  

Once again, the maritime industry is undergoing a period of transformation as it reduces its environmental impact and charts a course to a more sustainable future.  

Tags: decarbonizing, Heat power, Transport.Goods