This report is the result of a study on the future digitalization of inland waterway transport. Digitalization is affecting many sectors and industries. In transport and logistics the use of digital technologies is essential to streamline business processes between shippers and logistics actors. Several modes of transport have adopted different kinds of intelligent transport systems and are investigating the possibility of using (semi-)autonomous vehicles. Rapid technological developments have reduced the implementation barriers for such approaches. Public authorities are responded by providing the necessary regulatory frameworks and through specific digitalization initiatives. In a European context this includes the Digital Single Market initiative and the Digital Transport & Logistics Forum.
Methyl and ethyl alcohol fuels, also referred to as methanol and ethanol, are good potential alternatives for reducing both the emissions and carbon footprint of ship operations. As they are sulphur-free, use of methanol and ethanol fuels would ensure compliance with the European Commission Sulphur Directive. The European Maritime Safety Agency (EMSA) commissioned this study to gain more information about the benefits and challenges associated with these fuels and to evaluate their potential for the shipping industry.
Previous and current projects
Methanol has been investigated as a marine fuel in a few past research projects, two of which involved pilot test installations on ships. The Swedish EffShip project identified methanol as a promising marine fuel after studying alternatives and carrying out laboratory testing on a diesel concept engine. This led to further testing and development within the SPIRETH project, which led to the world’s first methanol conversion of main engines on a passenger ferry, the Stena Germanica, in 2015. Waterfront Shipping has commissioned seven new chemical tankers with dual fuel methanol engines to be delivered in 2016. New research projects underway or recently started include a German Project, Methaship, to develop designs of methanol passenger vessels, and the EU Horizon 2020 project LeanShips, which includes a work package to test a marine methanol engine in a laboratory. These new projects demonstrate the growing interest and potential of methanol as a marine fuel. No projects have been identified for ethanol on ships, but it has been used in diesel engines in road transport for many years.
Properties, safety and regulations
Methanol and ethanol are both colourless, flammable liquids. Methanol is the simplest of alcohols and is widely used in the chemical industry. It can be produced from many different feedstocks, both fossil and renewable, with the majority produced from natural gas. Renewable methanol is produced from pulp mill residue in Sweden, waste in Canada, and from CO2 emissions at a small commercial plant in Iceland. Ethanol is also an alcohol and is mainly produced from biomass, with the majority on the world market produced from corn and sugar cane. Both methanol and ethanol have about half of the energy density of conventional fossil fuels, which means that more fuel storage space will be required on board a vessel as compared to conventional fuels. They can also be corrosive to some materials, so materials selection for tank coatings, piping, seals and other components must consider compatibility. Methanol is classed as toxic so requires additional considerations during use to limit inhalation exposure and skin contact. Ethanol is not classified as toxic to humans.
The flashpoints of methanol and ethanol are both below the minimum flashpoint for marine fuels specified in the International Maritime Organizations (IMO) Safety of Life at Sea Convention (SOLAS). This means that a risk assessment or evaluation must be carried out for each case demonstrating fire safety equivalent to conventional fuels for marine use. Guidelines are currently in draft for the use of methanol and ethanol fuels on ships, for future incorporation in the newly adopted International Code of Safety for Ships Using Gases or Other Low-Flashpoint Fuels (IGF Code). This will facilitate the use of these fuels on board ships. The previously described Stena Germanica and Waterfront Shipping chemical tanker projects both carried out risk assessments and were approved for installation, demonstrating that safety considerations are not a barrier to the use of methanol fuel systems on ships.
Methanol is widely available as it is used extensively in the chemical industry. There are large bulk storage terminals in both Rotterdam and Antwerp, and it is transported both with short sea shipping and by inland waterways to customers. Ethanol is the most widely used biofuel in land based transportation and can be found at most large chemical storage hubs in Europe.
Methanol and ethanol both have many advantages regarding environment impacts as compared to conventional fuels – they are clean-burning, contain no sulphur, and can be produced from renewable feedstocks. Emissions of both methanol and ethanol from combustion in diesel engines are low compared to conventional fuel oils with no aftertreatment. Particulate emissions are very low, and nitrogen oxide emissions are also lower than with conventional fuels, although the amounts depend on the combustion concept and temperature. If a pilot fuel ignition concept is used with methanol and ethanol there will be a very small amount of sulphur oxide emissions which will depend on the amount and sulphur content of the pilot fuel.
The environmental impact of production and use of methanol “well to wake”, using greenhouse gas equivalents as an indicator of global warming potential, varies according to the feedstock. Methanol produced using natural gas as a feedstock has “well to tank” emissions similar to other fossil fuels such as LNG and MDO. Bio-methanol produced from second generation biomass such as waste wood has a much lower global warming potential than fossil fuels and is lower than ethanol by most production methods. “Well to wake” emissions from ethanol are lower than fossil fuels but the amount varies with production methods and feedstock. For example the ethanol produced in Brazil and in Sweden has much lower “well to tank” greenhouse gas emissions than that produced from corn in the US.
The behaviour of methanol and ethanol fuels when spilled to the aquatic environment is also important from an environmental performance perspective as ship accidents such as collisions, groundings and foundering may result in fuel and cargo spills. Both methanol and ethanol dissolve readily in water, are biodegradable, and do not bioaccumulate. They are not rated as toxic to aquatic organisms.
Cost and economic analysis
Prior to the recent oil price crash, methanol prices were below the price of low sulphur marine gas oil (MGO) on an energy basis for two years from 2011 to 2013, making it an attractive sulphur compliance option. With the low oil prices in 2014 and early 2015, methanol was comparatively more expensive but in late 2015 the price of methanol has started to move closer to the levels of MGO again. Cheap natural gas, a primary feedstock for producing methanol, contributes to lower production costs and thus methanol may be economically attractive again compared to conventional fuel alternatives. Ethanol prices have been higher than MGO traditionally, similar to other types of biofuels. Fuels from non-fossil feedstock, including bio-methanol, tend to have a higher price than fossil fuels.
Investment costs for both methanol and ethanol retrofit and new build solutions are estimated to be in the same range as costs for installing exhaust gas after treatment (scrubber and SCR) for use with heavy fuel oil, and below the costs of investments for LNG solutions. Operating costs are primarily fuel costs. The payback time analysis carried out for this study indicate that methanol is competitive with other fuels and emissions compliance strategies, but this depends on the fuel price differentials. Based on historic price differentials, methanol will have shorter payback times than both LNG and ethanol solutions for meeting sulphur emission control area requirements. With the current low oil prices at the end of 2015, the conventional fuel oil alternatives have shorter payback times.
Disclaimer: The content of this report represents the views of the authors only and should not be taken as indicative of the official view of the European Maritime Safety Agency (EMSA), or of any other EU institution or Member State. EMSA, SSPA and Lloyd’s Register assume no responsibility and shall not be liable to any person for any loss, damage or expense caused by reliance on the information or advice in this document.
The aim of the study is to explore the existing knowledge regarding the transportation of LNG and the use of LNG powered vessels on the waterways as well as to determine the possible scenarios involving an LNG leak that an incident response team could face.
Incident response is defined as the response required by local authorities, such as fire brigade, police, ambulance and harbour/river authorities, to deal with situations which have escalated outside the capability of initial responders, such as the ship’s crew, operators etc.
The information gained as a result of the study will be used to increase awareness in handling such incidents, make recommendations concerning the resources required for a response and provide guidelines for the training required for incident response.
The study provides an overall picture outlining the incidents that could emerge in dealing with LNG in inland navigation and how to respond to them. The study focuses on:
Much is already known regarding LNG specifically in shipping; however, that is relevant to sea-going transportation on a bulk scale – the emphasis of this study is “small scale”, which is reflected in the reduced quantities and limitations of inland shipping.
Air pollutant emission reduction, Alternative fuels, Energy consumption
Full electric vessels sail using only electrical energy stored in batteries/power packs. By definition a full electric vessel does not use a fuelled power source. This may be called ‘Battery electric’. Another definition is that a full electric vessel does not use an internal combustion engine (ICE). In that case fuel cells may be added to the system to generate electric power for sailing (Fuel cell electric).
A full electric propulsion system without an on-board fuel cell is charged by cold ironing, meaning the vessel needs regular re-charging time at shore. Due to the limited capacity of the battery pack, only short sailing distances are possible. This may not be an issue for ferries, but it is a hindrance for inland waterway transport vessels that are intended to cover large distances without the interruption of regular breaks to re-charge batteries.
Air pollutant emission reduction
Natural gas emits lower levels of nitrogen oxide (NOx) and also emits lower levels of particulate matter (PM). Compressed natural gas (CNG) is made by compressing natural to less than 1 percent of the volume it occupies at standard atmospheric pressure. It is stored and distributed in hard containers at a pressure of 200–250 bar usually in cylindrical or spherical shapes.
Liquefied natural gas or LNG is natural gas that has been converted to a liquid form for the ease of storage or transport by cooling natural gas to approximately −162 °C. Afterwards, it is stored at essentially atmospheric pressure. Liquefied natural gas takes up about one six hundredth the volume of natural gas in the gaseous state at atmospheric pressure or about 2.5 times less volume than CNG at 250 bar pressure.
Dual fuel engine: 80% LNG and 20% diesel:
These Dual-Fuel engines are based on diesel engines. The engines have been converted so they can also be powered by LNG fuel. The fuel is a mix of 80% LNG and 20% diesel.
Dual fuel / pilot diesel engine: 99% LNG and 1% diesel:
In this case the engine is fully optimized for natural gas combustion. This LNG Dual-Fuel system has already been in use for more than 10 years in coastal and ocean shipping. The engines are now also supplied for inland shipping. The LNG Dual-Fuel engines are specifically designed as Dual-Fuel systems so only a limited quantity of pilot fuel is required. The Dual-Fuel engine can nevertheless run fully on diesel. This involves proportions of 1% diesel and 99% LNG.
Air pollutant emission reduction
With the concept of fuel-water emulsion an add-on system emulsifies and mixes fuel with water, resulting in a homogeneous emulsion. This emulsion consists of oil droplets with a water nucleus, which is injected into the engine. A ‘micro-explosion’ divides each fuel oil droplet in numerous smaller fuel oil droplets, as these smaller fuel oil droplets ignite and burn easier than the bigger droplets. This results in the reduction of potential particle matter and soot creation zones, a cooling down of the combustion chamber temperature and a reduction of fuel consumption.
The share of water in diesel fuel usually ranged from 10% to 20%. The water used for the emulsion can be obtained from the conventional water tank in the vessel, but it is preferable to install equipment to obtain desalinated and demineralised water. The effectiveness of FWE is due to the quality of the emulsion, most efficient is an electronic control determining the required share of water. The fuel injection settings should be adjusted, to avoid a reduced power output. Although FWE has already been used in road vehicles and other mobile machinery, there is currently just one supplier (Exomission) installing this technology on inland vessels and there are only a few inland vessels with this system on board.
Air pollutant emission reduction, Alternative fuels, Energy consumption
Hybrid vessels may sail with the use of two or more energy sources. Main engines and generators using a fuelled power source are combined with an integrated electrical energy storage in the form of batteries/power packs, to hybridize either the energy production to ease up the main engine optimization. A way forward to full electric sailing (future) the electrical energy may be generated from fuel cells.
Sailing may be achieved by direct propulsion and/or electric propulsion.
Direct propulsion: The fuelled power source is the only source for propulsion and is directly connected to the propeller through the clutch.
Electric propulsion: Electricity is the only power source for propulsion. The electric energy may come from the battery/power packs and/or the generator sets. The power packs may be used for load levelling or peak shaving or for full electric propulsion, e.g. in areas where zero emissions is required.
The benefits of hybrid propulsion:
• improved vessel flexibility and performance;
• lower fuel consumption, optimise engine performance;
• reduced emissions due to lower fuel consumption;
• lower operating costs due to lower fuel consumption;
• lower maintenance costs;
• reduced noise levels.
Hybrid propulsion makes it possible to use the fuelled power sources more efficiently, by switching the source on only when needed. The fuel power will perform in a higher fuel efficiency area. This is also very beneficial to a proper operation of engine emission control systems such as an SCR catalyst and a DPF. In case the fuel power source is used to generate electricity, energy losses occur due to conversion from mechanical to electric power and from electric power back to mechanical power to generate the propulsion. For that reason it is very important to know the sailing profile in detail before fitting a hybrid system into a vessel.
Air pollutant emission reduction
Selective Catalytic Reduction of NOx (SCR deNOx) is a technology applied on diesel engines to reduce the NOx emissions, by injecting a urea-water solution (AdBlue) into the exhaust gas upstream of the SCR catalyst, generating ammonia (NH3). This is absorbed onto the catalyst, converting NOx in diatomic nitrogen (N2) and water (H2O).
A Diesel Particulate Filter reduces the particulate matter emissions from the engine exhaust gases. The most efficient DPF is the wall flow DPF, commonly made from ceramic materials with a honeycomb structure with alternate channels plugged at opposite ends. According to the Manufacturers of Emission Controls Association (MECA), particulate matter is captured by interception and impaction of the solid particles across the porous wall. The filter is designed to hold a certain quantity of soot. During the course of its operational hours, it gets loaded due to the high deposition of soot. This can result in increased back pressure on the engine and when not properly acted upon may lead to clogging of the filter. Therefore, it is important to maintain a sufficiently high average temperature such that the stored particle matter is regenerated (converted to CO2) and the filter is kept clean. This is needed to prevent it from becoming blocked and its function thereby being affected. Alternatively a special active regeneration system can be installed, which increases the filter temperature periodically to high temperature for fast filter regeneration.
SCR and DPF are often combined because then all gaseous as well as particulate emissions are reduced (by 70% or more) and usually the most stringent (future) emission legislation can be met. SCR and DPF often work together nicely leading to an increased SCR efficiency. One of the technical options is the “SCR on DPF technology”, where the DPF part acts as an SCR catalyst as well. This can lead to a more compact configuration.