Why is the Spotlight on Methanol?
With the advent of new and troubling climatic phenomena, governments and international organizations all across the world are scrambling for solutions to the increasing carbon and GHG content in the atmosphere. The spillover of this is being felt in the marine industry as well, such as IMO’s 2030 and 2050 goals. Methanol is shaping up to become a promising alternative fuel, as it ticks most of the boxes that shipping operators desire in a fuel of the future. And acceptability of methanol is increasing probably due to the consideration that a perfect fuel that solves all our problems may never be discovered in time.
What Boxes Does Methanol Tick on the Perfect Fuel List?
Methanol has many things going for it but indisputably the most important factor in its favor is the maturity of the technology in handling methanol. Methanol has many uses in production and manufacturing other than it being used as a fuel, such as being used in the production of polymers namely, plastics, paints, varnishes, and cleaning products. All this has put methanol on the list of top 5 transported commodities in the world already, with a remarkable base of knowledge regarding the handling and transport of methanol present. This is a considerable edge over competitors such as Hydrogen and electricity used to drive ships as there is a well-developed infrastructure and supply chain already available for the production and transport of methanol.
When deciding upon a fuel’s future, logistics plays a key role and here methanol scores well over its competitors. Methanol is liquid at room temperature which makes it much easier and less energy-intensive to store than its cryogenic counterparts such as ammonia, LNG, and Hydrogen. Not to mention that the already existing technology and infrastructure need only slight modifications to be repurposed to accommodate methanol. This can be extrapolated from the fact that there has been considerable success and acceptance in other sectors for methanol, such as in China where methanol is aggressively promoted, with global consumption of 57% methanol coming from the country alone, used in vehicles, heating equipment, etc. Europe is also promoting the use of methanol as a fuel, even high-powered engines such as those in drag racing have found methanol to be a replacement for gasoline.
The biodegradable nature of Methanol gives it a very clear edge over fossil fuels and some other energy alternatives. Being biodegradable simply means that even if there is a case of methanol slip or leak, methanol being highly biodegradable, its traces are removed naturally in about 7 days.
As of now, the cost of methanol per GJ is higher than not only the conventional fuels, but the cost of methanol produced from organic feedstock is more than that of fossil feedstock. The cost of the plant and the production capacity are the primary factors affecting the price but the encouraging fact is that big-name players such as Maersk are pursuing methanol as their choice of green fuel. And with others following suit, the price of methanol going down has essentially become a self-fulfilling prophecy.
The ultimate goal in the evolution of the production process of methanol would be to produce it completely from renewable sources. The carbon is obtained through carbon capture from the atmosphere and hydrogen is obtained via renewable sources such as wind and solar power. But in transition, for the next few decades, the methanol produced from biomass, especially the abundance of it in southeast Asia (Indonesia, Malaysia, etc.) namely the oil palm fronds are a viable alternative. The yield is high enough and overall there is no GHG emission.
Penetration of Methanol in the Industry
The induction of methanol into the marine sector has been going on for quite some time, with the Green pilot project, a retrofit of a vessel built in 1996, One of the two Cummings engines was replaced with a Weichai or Scania diesel engine to burn methanol. With passing time retrofits have become more streamlined than the complete replacement of engines.
The first major name in the list of conversions is the Polish Stena Germanica, its retrofitting started in 2015 and later all 4 of its engines were converted to dual-fuel, with the option of using recycled methanol and since it was one of the initial conversions, it retained the ability to use conventional fuels for reliability. Recently Stena has joined hands with Proman, the world’s largest producer of methanol, to develop retrofitting and supply chain solutions for existing vessels to assist them to adapt to methanol in the future.
There are many ways for the conversion of an engine to use methanol and each has its challenges, the Green pilot project changed the fuel injectors and remapped the engine ECU. The fuel composition was also changed to add a 5% combustion improver to ensure reliable combustion. The fuel injectors and atomizers have to be changed to compensate for the fact that methanol has a lower energy density than heavy fuel.
MAN’s B&W ME LGI two-stroke engine powered by methanol is being used in ships that transport methanol and is increasingly finding use in other ships with the change in economy regarding methanol.
The most recent additions are the ones from Mitsui O.S.K lines (MOL) which has the most advanced methanol combustion system. MOL’s recently inducted vessel, Capilano Sun is able to achieve Tier III NOX requirement even without a scrubber. This has been achieved by injecting water along with the methanol. The water injection along with methanol in general provides multiple benefits. The temperature of the entire cylinder remains more uniform as the water vaporizes in the cylinder preventing the formation of “hot spots” which reduces engine performance and life. The vaporization of water also reduces the temperature thereby allowing for a greater air-fuel ratio, in turn allowing for more aggressive ignition timings and greater turbocharging. The water vaporizes and creates pressure driving the piston rather than the energy being wasted generating heat.
Challenges With Methanol
The largest challenge associated with methanol on its way to take over as the fuel of the future is the low energy density. Heavy fuel oil has 2.5 times the energy density per unit volume than methanol. This means that larger tanks and more volume of fuel will be required for the same journey. Most of the ships accommodate methanol by converting the ship’s ballast tanks to store methanol. The unfortunate result of this is that vessels that undertake long voyages and deep-sea shipping such as bulk tankers (VLCC / ULCC) or dry bulk vessels will be unable to convert to methanol at all for the foreseeable as there will be no bunkering options or ports readily available.
The next challenge at hand is the method of production of methanol, which for now is a net polluter of the world. The production which, at the time, is done by fossil feedstock contributes to GHG emissions even more than the direct burning of fossil fuels. Achieving economies of scale on its production in a carbon-neutral manner is imperative.
Methanol produces formaldehyde upon incomplete combustion which is a known pollutant and carcinogen, but this problem does not occur in high-temperature diesel engines (greater than 1500 degrees).
It’s not that methanol is the ideal fuel of the future with no drawbacks or risks associated. Methanol has inherent challenges associated with its use, such as it being poisonous. A dose as low as 10ml can cause enough damage to the optic nerve to cause blindness and a dose of about 30ml can cause death. Absorption of methanol on the skin, inhalation of vapors, eye contact, or ingestion can cause methanol poisoning. The flame of methanol may not be visible under daylight as it burns at a colder temperature than fossil fuels. So appropriate gear such as protective and flame retardant gear is required, along with breathing equipment as only a dangerous dose of methanol is detectable by smell.
The next negative side of Methanol is its corrosive nature. Methanol corrodes certain metals such as carbon steel and aluminum, so the design of tanks, hoses, storage, engine components, and supply line has to be designed with this in mind. For example, the hoses and the storage tanks are double-walled to prevent leakage. The international code of safety for ships using gaseous or other low flashpoint fuels is known as the IGF code. This provides the regulatory framework for the implementation of alternative fuels on ships. This code entered into effect on 1st January 2017. By imposing mandatory measures for installing, operating, and monitoring machinery and systems this code aims to minimize risk to the environment and crew.
In terms of investment, methanol-powered ships are comparatively expensive than traditional fossil-fuel-powered ships. Maersk has placed an order for 8 dual-fuel ships with Hyundai Shipyard of South Korea. These ships have a price tag of $175 million each, which accounts for 10-15% more than the traditional bunker fuel ships. High initial investment often becomes the major challenge for any new technology in finding adaptability across the industry.
Looking to the Future
Methanol shows great potential as a fuel of the future as it has favorable traits of reducing GHG emissions, has low emission, and is easy to handle but at the same time, the fuel is also highly corrosive in nature and requires a huge investment in transforming the propulsion systems on ships. Even though methanol is a cleaner-burning fuel than conventional fuels like marine diesel, presently methanol is predominantly being produced in a carbon-intensive manner. Since the change to greener fuels is non-negotiable, and it’s unfortunate that none of the options on the table is mature enough to take on the mantle of being the new fuel. The choice right now is more inclined towards what limitations we can tolerate rather than the merits a fuel has. However methanol, like only a few others of its ilk, shows promise, that one day its advantages will outgrow its limitations.