About one year ago I wrote an article on fuel options and other ways ship owners could reduce fuel costs in the face of the IMO’s 2020 Sulphur Cap. Since then, fuel prices have gone up and down, but with a clear indication that that they will increase post 2020. Ever since the IMO’s confirmation that the Sulphur Cap will be enforced as of January 1st 2020, speculation on alternative fuels has ramped up. Especially since the IMO raised the bar with an even more ambitious goal to reduce 50% of CO2 emissions by 2050. However, the marine fuels that were chosen will not help the industry reach the 2050 target. As the industry continues to search for the “holy grail” fuel, they face more short-term challenges with the upcoming Sulphur Cap, forcing shipowners to look at fuel-saving alternatives to avoid negative financial impact. With less than one year to go, I’d like to share my view on some of the options for fuel-saving technologies that could be deployed now.

Fuel Alternatives

While parts of the industry seem to have decided on LNG as the next maritime fuel, I see a huge risk with the potential consequences – not to mention the challenge of cutting CO2 emissions. LNG does cut CO2 reductions by ~10% but there is also a corresponding methane slip – methane is ~30 times more aggressive than CO2 (some claim it is even higher).

Biofuel has also been raised as an option but there’s a big question mark for the environmental impact of the supply chain and that most biofuel actually leaves an even larger CO2 footprint than the conventional options that we have today.

The only theoretical alternative that could decarbonize the industry is hydrogen in combination with fuel cells. Lately there’s been some great progress in this area, and I sincerely hope that R&D and industry experts will find a way to overcome the well-known challenges of hydrogen as a marine fuel.

Batteries & Fuel Cells

If you look at how Tesla and Toyota are disrupting the auto industry, it seems likely that these developments will impact fuel cell and battery use in the maritime industry. Production of battery-operated ferries for use in near-coastal waters is ramping up in Norway, Netherlands and Belgium. This is still not an option for large transport and cruise ships in the foreseeable future but the improvements in battery technology will continue and that will only push the development in the right direction.

When it comes to fuel cells, on the other hand, they have the chance, theoretically, to replace combustion engines in the long term if hydrogen can be used as the main fuel. Not least because it’s possible to combine fuel cells with other fuel types like methanol. There are some projects underway such as the Golden Gate Zero Emission Marine’s hydrogen-powered ferry by the end of 2019, Royal Caribbean has two cruise ships in the works, and Belgian shipowner CMB Group just announced its plans to launch the first hydrogen-powered bulk carrier. We’re still far off from seeing how well they will perform and what kind of supporting infrastructure there will be, but I sincerely hope that they will succeed for the sake of the industry.

Focus on Fuel Savings

Regardless of the current or future fuel mix, the quickest way to reduce emissions is to invest in fuel efficiency and fuel-saving technologies. More importantly, these types of alterations will continue to yield a return on investment – regardless of which fuel type is used in the future.

Savings through Waste Heat Recovery 

In my opinion by far the biggest potential cost savings and fuel savings lies in waste heat recovery – and there are several technologies out there:

#1. Conventional Waste Heat Recovery
We’re all familiar with how jacket water from engine cooling is typically used for fresh water generation, potable water and pool heating. These are all great ways to reuse waste heat, but with the technology that exists on the market today, that heat could be turned into something more valuable and be used much more efficiently.

#2. Heat to Power 
This is where my company’s technology comes in, and the potential here is significant. Climeon’s Heat Powersystem is turning waste heat from ship engines into clean electricity and save fuel at the same time. The technology is a low temperature ORC technology with a compact and modular design, built to fit in places with limited space. One of the top benefits with electricity is that it is flexible and can be used for many purposes, i.e. to reduce the hotel load or for propulsion.

Steam turbines is another option to utilize the waste heat from ship engine exhaust. Thermodynamically, steam turbines achieve an isentropic efficiency of 20% to 70%. Economically, however, the turbine generates power at the efficiency of the steam boiler. Steam to power is not really a new application and have been deployed on several ships. On a large cruise ship a steam turbine could generate large amounts (MW) of electricity, however, one of the biggest challenges has been to maintain a high efficiency when the engine load is constantly changing.

#3. Heat to Cooling 
Absorption chillers are becoming more and more interesting to ship owners despite the history of several failing projects in the past. The cooling demand in tropical waters, such as the Caribbean, is very high and absorption chillers tend to have a high efficiency. Johnson Controls have had great success re-introducing the absorption chillers to the industry and I think this is a great option for efficient heat recovery. However, what many tend to miss is that they can also be combined with other WHR technologies that are using the same heat source (i.e. low temp ORC technology). Electrical chillers are becoming more and more efficient and soon they will reach a COP (Coefficient of Performance) where it will make more sense to generate cooling from electricity than to use an absorption chiller. However, I would like point out the possibility of running both technologies in serial connection to optimize the energy efficiency.

#4. Waste to Energy
There are technologies that can take onboard waste (food, garbage, etc.) and turn it into useful energy, similar to a small biomass plant. The Norwegian company Scanship is a great example where they are working on how to maximize the use of this energy. This application should be a great opportunity to connect H2P (heat-to-power) technologies for direct use, but also for more conventional use, i.e. to boost existing heat sources (i.e. the HT circuit) that already have several heat consumers.

Is all this enough to comply with 2020 and future regulations?

Right now, the industry is mostly looking to fuel solutions to help reach this target and also overlooking the impact that fuel efficiency measures could have on both their current and future operations. The main purpose of the 2020 regulation is to reduce harmful emissions in sensitive areas and near coastlines where people live.

However, the more challenging long-term goal is still to reach a 40% reduction in CO2 emissions by 2030, and a 50% reduction by 2050. While scrubbers (in particular) and LNG are ways to comply with the Sulphur Cap, in my opinion they are not the solution that will help the industry reach a 50% reduction by 2050. There are viable technologies that can help ship owners reduce fuel consumption and cut emissions now, but none are enough. The industry needs more sustainable fuel options that will have a larger decarbonizing effect to be able to reach the 2050 target.

We must start thinking in synergies

I am also convinced that stand-alone green technologies are not the answer. From the perspective of a clean-tech provider, I know we can make a bigger impact on fuel efficiency and GHG reductions by finding ways to make different technologies work together. If we recognize that we are all working toward the same end game – we can share knowledge across the spectrum and make the industry more sustainable. In fact, I’m already working on another article about this – so if you have any ideas, please reach out!