This article handles one of the biggest problems the maritime industry has to face now and in the future: reducing the carbon and other air emissions to limit the industry’s impact on climate change. The paper discusses the following topics: the decarbonisation of the maritime industry in general; biofuels use for the transition phase, alternative biofuel conversion technology, advantages and disadvantages of biofuels and hemp as an alternative biomass resource to produce biofuels and how their properties can overcome the critics against a biofuel implementation into the shipping industry.
The first part of the article discusses the decarbonisation of the maritime industry in general. This part will describe the current state, in respect of, e.g., laws, regulations and rewards. The second part discusses biofuel uses for the transition phase to a more carbon-neutral shipping industry in regards to infrastructure & storage, energy density, maturity of technology, green credentials, independency, availability, flexibility, price and different qualities and characteristics of the biofuels. The second part will also illustrate why biofuels can play a significant role in the shipping industry’s future, especially in the transition phase to a more sustainable shipping industry with many different alternative energy sources. The third part will mention an alternative biofuel conversion technology, which has a promising potential to produce biofuel more profitable. Finally, the last part will discuss the advantages and disadvantages of biofuels and hemp as biomass resources. Currently, there are still many critics regarding biofuels. One of the biggest concerns is that the production of biofuels will use a lot of agricultural lands to produce biomass, whereby the land would be otherwise used to produce food and feedstock. Subsequently, the supply of food and feedstock would be limited, and the price of such products would be higher, which would hurt the whole society. The last part of the paper discusses what benefits hemp as a biomass resource could bring to the biofuel industry.
1.1 Research Objectives and Research Question
1.1.1 Research Objectives
This research aims to examine how biofuels can be implemented into the shipping industry in an economically feasible and, most importantly, sustainable way. Preliminary research indicates that biofuels have great potential in the shipping industry but are facing challenges. Previously, many articles were written explaining the current state of biofuels in general, but also, especially in the shipping industry. This paper will use the previous articles’ findings to build on them.
1.1.2 Research Question
The article will be discussed in the first section how biofuels can help decarbonise the maritime industry and how they can potentially benefit the shipping industry to transition into a more sustainable industry.
In the next section, the article will handle the matte that right now, biofuels have limited economic usability and what could be a potential alternative to produce biofuels more economically to become a real alternative to other fuels made from hydrocarbons. The last part of the article will handle the question and concerns the society has against the production of biomass for biofuel production. The results could then open up new debates for further research topics.
As a research philosophy, the article focused on Interpretivism, which underlies the research philosophy of qualitative studies. Furthermore, since the research performs an observing role of the current state of biofuels in the shipping industry with a focus on implementing the findings of other industries apart from the shipping industry, this research philosophy was chosen since most used articles to conduct this article were qualitative researches. The research type which was chosen for the article is deductive since it starts with an established theory of other previous articles and builds onto it. This research type was selected because an inductive research type would be difficult to conclude from the ground up without sufficient resources. The data for the study was collected through multiple articles written at various points in time, making this paper longitudinal. The methodology utilised in this study is collecting necessary data qualitatively based on a review of relevant scientific papers and reports from the shipping industry and other relevant industries (Mardan, 2015). Considering that biofuels for shipping are viewed as a potential alternative fuel after the introduction of the Paris agreement, research in this area was done, but is still very limited generally due to that shipping experts are not experts in other fields, so their approach in doing research is limited to what they are experts in (Mardan, 2015). The data analysis method used in the paper mentions the assumptions extracted from research papers and compares them with other research papers from different industries. The scope of this research paper is limited to the study of research papers from different sectors and has to compare them (Mardan, 2015). Additionally, the paper used hemp-based biofuel in shipping to discard the critiques of other research papers and the introduction of another biofuel conversation process. Therefore, aside from the advantages and disadvantages, this report deals strictly with introducing hemp and another biofuel conversion process. Furthermore, since it is indistinct that hemp is rarely used as biomass to produce biofuel right now, the availability, capacity, scalability, cost projections and adoption are not discussed in this paper.
2. Decarbonisation of the maritime industry
The shipping industry needs to work on its overall carbon footprint to comply with, for example, the Paris agreement and the European green deal. Moreover, the IMO established a Greenhouse Gas Reduction Strategy in 2018 as the global regulatory authority (DNV, 2021). One of the objectives is to reduce carbon intensity by 40% by 2030 compared to 2008 (DNV, 2021). The target is to reduce GHG emissions by improving vessels’ energy efficiency and introducing new technologies and low or zero-carbon fuels. In June 2021, the International Maritime Organization (IMO) adopted extensive new CO2 regulations applicable to existing ships, whereby the Energy Efficiency Existing Ship Index (EEXI) addressed the technical efficiency of vessels, the Carbon Intensity Indicator (CII) rating scheme addressed the operational efficiency, the enhanced Ship Energy Efficiency Management Plan (SEEMP) addressing the management system. The SEEMP is an operational measure that establishes a mechanism to improve a ship’s energy efficiency cost-effectively (IMO, 2021). There are mid-term goals such as energy-efficiency measures for new and existing ships, using new indicators and long-term goals such as developing zero-carbon fuels (Andersen and Gl, 2020). So, it can be concluded that alternative fuels will play an essential role in the future. There are also port discount schemes, which are set in place to reduce the air pollution in ports and their neighbouring area; such schemes are ESI (Environmental Ship Index), EPI (Environmental Port Index) and CSI (Clean Shipping Index). ESI scheme grants Vessels with clean engines and fuels a discount in port, which is commensurate with the level of cleanliness. Therefore, ESI promotes ships to use cleaner engines and fuels. The ESI-Score ranges from 0 for a ship meeting environmental performance regulations in force to 100 for a best-performing ship which emits no SOx and no NOx and reports or monitors data to establish its energy efficiency (environmentalshipindex.org, 2022). The EPI scheme is based on major influencing factors, including CO2, SOx, NOx and particle levels; the EPI shows a ship’s maximum tolerable environmental impact while at the port. The index applies only to ports in Norway (epiport.org, 2022). The CSI comes from a non-profit organisation that offers a voluntary environmental label for ships and shipping companies and provides market incentives for clean shipping. CSI applies only to ports in Sweden (DNV, 2022). These schemes also give some rewards for companies to implement greener solutions. Nevertheless, there are still a couple of problems with implementing greener solutions. All the goals, regulations and reword schemas aside, the shipping industry was established long ago, and there are a lot of ships around the world, which someday in the future, have to operate carbon neutral. To run a current world fleet carbon-neutral, they either have to have refitted engines or be replaced by ships with new engines. A company needs the technology and knowledge available to refit an engine, which could be a problem. Another problem with refitting and building new ships is the availability of shipyards and the lack of skilled workers. Another problem is that shipping companies have large fleets with vessels of various ages. Getting the entire fleet carbon neutral for shipping companies will be a significant undertaking. Shipping companies will have several options: they can scrap the oldest ships and replace them with new ones or retrofit ship engines to run with alternative fuels. Shipping companies will have a problem with vessels nearing the end of their life cycle, and for which it does not make economic sense to scrap them right now or retrofit them since they are almost at the end of their life cycle. This point is where biofuels come into play since they can be directly used in currently used combustion engines.
3. Biofuels for the transition phase
3.1 Infrastructure & Storage
Biofuels have the advantages that they can use the infrastructure and storage facilities which are already in place. Compared to other fuel options such as LNG, LPG, Methanol, Hydrogen and Ammonia, biofuels can be directly transported, stored and consumed the same way current fuels are. For other fuels, the infrastructure and storage have to be built, which will take technology development, time, resources and skilled worker, which will take time. To reach the target set by the Paris agreement, the transition has to happen now and fast, and biofuels have the potential to help in the transition phase or even be an alternative fuel in the future. Also, alternative fuels such as methanol and hydrogen are expected to be produced through the help of solar and wind farms; these farms have to be established before the production of these alternative fuels can take place. On the other side, biofuels come from biomass, which must be planted, harvested and processed and most of the needed equipment and infrastructure are already in use. So, biomass production for biofuels would be less of a problem; biofuel production’s problem lies in the economic feasibility of scaling up the biofuels production (Bunse, 2021)
3.2 Energy density
The energy density of biofuels is greater compared to other fuels. That means they have the same energy in a smaller volume than the other fuels. Subsequently, they need smaller fuel tanks; in fact, they can use the currently installed fuel tanks and other systems, which are currently installed. This can be considered a significant advantage since the current ships would not have to be retrofitted to accommodate the different fuels. Another advantage of biofuels is that the bigger the fuel tanks are, the smaller the net tonnage or, in other words, the area available for commercial use would be. Additional, since the energy density of biofuels, is higher, the time to bunker is shorter than that of other fuels (Carvalho et al., 2021)
3.3 Maturity of technology
Regarding the maturity of the technology, biofuels have a clear advantage compared to other alternative fuels. The history of biodiesel goes back over 150 years (Mardan, 2015). As early as 1853, chemists E. Duffy and J Patrick led the field of biofuels with the first-ever transesterification of vegetable oil (Alaoui, 2020). Furthermore, on August 10, 1893, Rudolf Diesel’s initial engine model was the first to run on its own in Germany (Ingle, 2021). This day is celebrated as the international biodiesel day (Mardan, 2015). The Diesel engine was powered by peanut oil, and during the 1900 Paris Exhibition, Diesel was awarded the “Grand Prix,” which was the highest prize at that time (Mardan, 2015). In 1908, Henry Ford developed his Model T car to run on ethanol, a biofuel derived from hemp or corn (Mardan, 2015). G. Chavanne, a Belgian chemist, is credited with inventing biodiesel as we know it today. In 1937, he was issued a patent titled “Procedure for the transformation of vegetable oils for their uses as fuels” (Mardan, 2015). The patent mainly describes a method of esterifying vegetable oil with ethanol to reduce the viscosity of pure vegetable oil and so improve the quality of vegetable oil used as fuel (Mardan, 2015). Biofuels have attracted minimal interest due to massive access to low-cost petroleum-based fuels. Following the oil crisis of the 1970s, interest in biofuels returned, and in 1977, Brazil developed the first industrial technology for producing biofuel (Mardan, 2015). In the 1990s, additional efforts in Europe and South Africa increased biodiesel development (Mardan, 2015). With global warming caused by GHG emissions and rising environmental awareness, interest in biodiesel and other alternative energy fuels has grown.
3.4 Green credentials
All of the alternative fuels provide air emissions reduction advantages. This is mainly due to their lower sulfur content and, consequently, lower emissions of sulfur oxides (SOx) and particulate matter (PM) (SASB, n.d.). In addition, due to improved combustion conditions, certain biofuels also produce less nitrogen oxide (NOx) emissions; however, these advantages vary depending on the fuel and feedstock used as well as engine load (Zhou et al., 2020). Compared to heavy fuel oil or marine diesel, biofuels for maritime applications can lower SOx, NOx, and PM pollutants, improving air quality globally and in and around harbours in particular. The biofuel not only have naturally very low sulfur content. Further, they can potentially deliver additional environmental benefits when compared with low-sulfur fuel oil or marine distillate (Kass et al., 2018). Since Biofuels have very low sulfur content, the exhaust gases from the combustion also have low SOx emissions and particulate matter, potentially lowering the harm the exhaust gases have on human health compared with conventional marine fuels. Reducing SOx is beneficial because SOx increases radiative forcing by around 3%, which can be considered another trade-off. This is due to the sulfur emissions’ particles, which reflect light and cause cloud formation. Another plus of biofuels is that the carbon released upon combustion was extracted from the atmosphere during the cultivation of the biomass used to make them. Because of the carbon uptake during biomass production, the Greenhouse Gas (GHG) emissions from biofuels can end up being net negative (Kass et al., 2018). Biofuels made from plants or other organisms not only have the potential to reduce overall Greenhouse Gas (GHG) emissions significantly, but they also biodegrade quickly, presenting much less of a hazard to the marine environment in the case of a spill (Chryssakis et al., 2014). There are several other critical benefits of biofuels. One key advantage, for instance, is that the lower viscosity of biofuels relative to HFO means that the energy needed to heat HFO to reach optimal viscoelasticity can be decreased. This is in addition to the environmental and energy benefits of using biofuels as an HFO substitute or blending agent. The previously mentioned means that the energy required to heat and process traditional marine fuel oil before fuel injection could be reduced by lowering the overall viscosity. Therefore, biofuel presents a means of enhancing vessels’ total energy efficiency (and CO2 emissions), offering a route to achieving future EEDI reduction targets (Kass et al., 2018).
Family farms can be financed using biofuel and biomass revenues. Money remains in the country instead of being sent to other parts of the world when energy is produced domestically. Biomass production has the potential to assist us in growing our way out of the current economic crisis (Davis, 2009). Growing crops locally for biomass production would also create new opportunities, such as businesses and jobs directly connecting to the biofuel industry. Through new businesses and jobs in the biofuel industry, there will also be greater demand for other sectors which are not related to the biofuel industry at all, but are basic needs for a fulfilling life, as a place to live (e.g. bought or rented house/apartment), necessities consumer goods (foods and drinks etc.) and a means of transportation (e.g. car and bicycle). Overall, a new industry will most likely bring great prosperity to the country’s entire economy.
The fuel that will be most used in the future depends on the type of ship’s engine. Therefore, the engine choice for a vessel is determined by the assurance of marine fuel availability during the engine’s lifespan. Diesel engines continue to be the engine technology of choice for most vessels. Diesel engines have been continuously upgraded through time to be more fuel-efficient, using less fuel for propulsion (Hsieh and Felby, 2017). If the vessels have an access to fuel depends on the fuel availability at the port, whereby the availability depends on the position of the port. Ports with high cargo turnover and lots of calling vessels will have a steady supply of fuel. Contrary to minor ports, which don’t have the facilities to deliver fuel regularly, will have a problem with attracting vessels for bunkering. (Florentinus et al., 2012). When introducing other alternative fuels such as hydrogen and methanol into the shipping industry, the infrastructure for such products would be even more limited than that for current fuels, which could be directly used for biofuels. Then there is the question of the availability of biomass for biofuel production. For example, slightly more than 5% of the world’s agricultural land would be needed to produce 300 M Tonnes of Oil Equivalent (TOE) biodiesel using today’s technologies (first and second-generation biofuels). Biofuels have a problem, which is that they sometimes have water residues, so corrosion problems and other issues about the durability of biofuels in long-term storage on ships need to be addressed. However, the price of oil and gas will impact how fast biofuels evolve. As a result, biofuels will only have a minor market share in the marine fuels sector in the next ten years. However, if sufficient quantities of biofuels can be produced responsibly and at a competitive price, they are expected to play a more significant role by 2030 (Chryssakis et al., 2014). By 2030, biofuels might account for 5 to 10% of the world’s maritime fuel mix, or a market of 16–33 million tons of biofuel, if regulatory and market factors are in place (Kronemeijer, 2016). Creating an international ECA and monetary rewards in seaports for vessels with lower air pollution will drive the need for biofuels even more. Biofuel-producing plants should be positioned near important ports or bunker stations to maintain competitive prices. One of the essential components for a successful deployment is the guarantee of marine biofuel availability (Hsieh and Felby, 2017).
A reliable biofuel supply can be started in the short sea shipping industry, which has established routes and significant shipping volume. These vessels use fixed routs from port to port and are always close to a port, so they would benefit from frequent refuelling. Ferry routes and short sea commercial vessels fall under this type of activity. The first biofuel demand will most likely focus in the vicinity of harbours with restrictive pollution regulations, like the areas around Europe, the Nordic territory, and the north American West Coast (Hsieh and Felby, 2017). On the other hand, implementing biofuels in deep-sea shipping would take longer to put into practice and is only possible if the fuel would be produced in sufficient amounts at a cost-efficient way or as a result of international regulation (Hsieh and Felby, 2017). Large oceangoing cargo ships burn tons of fuel before bunkering again. Thus, vessels have not yet been using pure biofuel because it is not as widely accessible as it should be. However, the problem of decreased emissions and cost competitiveness can be resolved by blending biofuel with conventional fuels. During the transition of the shipping industry into a more sustainable industry, drop-in fuels would be the best choice (Hsieh and Felby, 2017). Given the diesel engine’s excellent efficiency, a significant transition to a different standard marine propulsion technique is doubtful in the near to medium term (WG III contribution to the Sixth Assessment Report List of corrigenda to be implemented, 2021). Finding the suitable fuels that work with diesel engines takes up much of the power on working to mature the biofuel technology for the shipping industry (Hsieh and Felby, 2017). As has been done in the vehicle transportation industry, biodiesel mixtures up to 20 per cent MDO/MGO appear hopeful. In some aspects, biofuels are also technically superior to HFO and MGO and, at the same time, suitable for current engines and the infrastructure (Hsieh and Felby, 2017). Modern marine diesel engines can run on innovative fuels, including dimethyl ether, bio-LNG, ethanol, and methanol (Hsieh and Felby, 2017). Still, their availability restricts how extensively they may be used in shipping. Even though these new fuels may be compatible with newly built vessels, there is also no facility or financing in the alternative fuels supplying to allow for their introduction (Hsieh and Felby, 2017).
Biofuels also bring flexibility to the energy sector compared to other energy sources, such as solar and wind energy. Solar plants are seen as alternatives, but when they are set up, the land is no longer usable for other purposes, such as agriculture for food and feedstock. When planting an energy crop, such as hemp, the land use would be more flexible. When the energy is exacted to be high, farmers could plant more energy crops, and when the energy demand is lower, they could use the land for other crops. Additionally, an energy crop such as hemp could be planted at the end of the season so that the land could be used for most of the year for food and feedstock cultivation.
The first generation of biodiesel feedstocks is usually expensive, and the accessibility is limited. Further, the biodiesel price depends on the feedstock price. The competition from the food, pharmaceutical, and cosmetics industries generally also limits the availability of vegetable oils (palm, soy, and canola) (Hsieh and Felby, 2017). The simultaneous generation of feed and food protein is a significant component of oil production. This is notably true of canola and soybean, two critical vegetable protein sources. A not-so-significant crop for oil is hemp right now, but it could become one at one point in the future. The largest oil crop, palm oil, is primarily consumed as food and not as fuel, and its by-products are used as compost or, to a lesser extent, used as feedstock (Sridhar and AdeOluwa, 2009, pp.341–355). Biofuel will need to be blended with conventional fuel oil for its supply to be economically achievable. The fuel demand necessary for coast and deep-sea shipping are greater than what biofuel could achieve by itself (Hsieh and Felby, 2017). Prices for biofuel feedstock differ based on the source. In addition to fluctuating seasonal prices, feedstock prices also depend on labour costs and land use, increasing their volatility even more (Hsieh and Felby, 2017). In contrast to producing marine biofuels alone, biofuels processes, which produce aviation fuels and marine biofuels at the same time, would have a greater chance of success in the biofuels market since the value-added cost of aviation fuel would upset that of the lower graded marine biofuel and the overall cost of energy and refining would be covered by the selling price of the higher-quality clean fuel. The paper will again come to that aspect of producing high-grade fuel (Hsieh and Felby, 2017). The current price of crude oil affects the financing and attention given to developing new marine fuels. Given the existing infrastructure that supports fossil-based fuels, there is not much economic encouragement to shift to other fuels when oil prices are low. However, creating fuels that complement existing fossil-based fuels has regulatory and environmental benefits. Biofuels that work with marine engines are still in the early stages of development. Creating price-competitive biofuel on a big scale is still challenging without a sufficient feedstock supply and efficient processing methods. The rising global population and shifting dietary practices have raised the price and supply of agricultural waste, but biomass resources becoming more unpredictable due to weather crises. The market value of biofuels is still based on the cost of crude oil, irrespective of feedstock price. According to experts, the oil price must increase to at least $60 per barrel before biofuels from agricultural waste can compete with traditional fuels. The demand for biofuels consequently declines when crude oil prices are low. Fossil marine fuels have an additional comparative advantage since, from the perspective of a vessel operator, fuel expenses might account for up to 50% of operational costs. Furthermore, biofuels possess extremely low sulphur content and decrease ship emissions while also improving local air quality. So once stronger sulphur emission regulations come into place, biofuels can be introduced into the maritime industry since they can comply with the requirements and be more competitive due to increased demand. Even though ship operators also have the option of using scrubbers or purchasing low-sulfur fossil-based fuels, the present environmental regulations, in addition to the inevitable worldwide GHG emission limits (International Maritime Organization, n.d.), will also increase the need for drop-in biofuels by reducing the dependency on fossil fuels.
Especially in marketplaces where fuel prices are insignificant compared to overall operating expenses and unpolluted air is valued as a commercial quality, biofuel can be a very appealing alternative. Improvements in technology in biofuels production are anticipated, which will reduce the overall costs. Nevertheless, right now, biomass conversion technologies are still in their early stages compared to fossil fuels; it should be noted that only the sugars are presently transformed to fuel on a viable scale, while other conversion technologies are now in development and are not operational at a commercial scale (Hsieh and Felby, 2017). At oil prices of around $60 per barrel, first-generation biofuels like biodiesel made from vegetable oil or ethanol made from corn or sugarcane can challenge fossil fuels as a fuel (Hsieh and Felby, 2017). However, due to the newer and less efficient technology used to produce second-generation biofuels, their production costs are higher. At oil prices near $100 per barrel, a variety of second-generation biofuel technologies will likely become commercially viable (Cazzola et al., 2013). Expanding interest in biofuels in the maritime sector is expected to build upon on stricter ecological rules of air pollution and greenhouse gas (GHG) emissions or new company types like low carbon production to contribute to the customer satisfaction; suppose that biofuels are industrialised and accessible for the maritime industry in the right amounts (Hsieh and Felby, 2017). There may be a market for low-carbon transport services because transportation expenses for lots of consumer goods are only a tiny portion of the overall cost (Hsieh and Felby, 2017). To properly assess how and when 2nd generation biofuels will be able to compete against the price of fossil fuel, predictions about technology development, oil prices, and regulatory frameworks must be made. Each of these predictions carries a certain amount of risk. Suppose biofuel or alternative fuel regulations are implemented in the marine industry. In that case, there will be no rivalry with fossil fuels inside specific markets, and a separate market will be established to set the price for maritime biofuels. In the beginning, marine biofuels will probably be used more extensively in inner-city waterways, hinterland transportation in inland rivers, and coastal green zones, especially ECA / SECAs. Around highly populated locations, ship operators would be required to follow legal requirements and implement cleaner fuels. With stricter emission regulations in place, it is expected that the future fuel supply will be made up of a variety of fuels derived from various sources, including crude oil, natural gas, biomass and electricity (Hsieh and Felby, 2017).
3.9 Qualities and characteristics
By lowering the sulfur content and potentially providing better particle and emission profiles than petroleum fuels, biofuels have the potential to provide synergistic benefits when mixed with them. Biofuels can be low in sulfur and nitrogen while simultaneously having a low greenhouse emission, depending on the biomass feedstock and processing parameters. Each biofuel has unique characteristics that will determine which marine fuels it can be blended with, replaced by, or partially replaced by. However, the sulfur content of each one is relatively minimal. Compared to liquid hydrocarbon fuels, oxygenated biofuels have lower energy densities; nevertheless, the bonded oxygen atoms work as oxidisers to lessen the creation of particulate matter (PM) during combustion. Nonoxygenated hydrocarbon biofuels may need fractionation depending on their intended application because they have wider boiling ranges than regular marine diesel. However, there is still a great deal of dissonance surrounding the necessary standards for quality and the need for further research into blending biofuels, such as the probable demand to remove water (since oxygenated fuels might have a hydrophilic nature) or any unwanted particles. (Hsieh and Felby, 2017) Marine distillate fuels can be blended with biofuels like biodiesel, F-T diesel, renewable diesel, and upgraded bio-oil. Studies by ExxonMobil, MARAD, and others have demonstrated considerable PM reductions when biodiesel is blended into MGO (Kass et al., 2018). Currently, only biodiesel (at concentrations of up to 7 vol. per cent) is permitted for use with MGO as a marine fuel. The obvious environmental benefit of oxygenated fuels is the reduction of particulate matter (PM), and significant reductions can frequently be obtained at only a 10% blending level. Any attempt to combine bio-oils with MGO will require using surfactants to create an emulsified fuel blend because bio-oils cannot be mixed directly with distillates. Emulsified fuels often have a short shelf life because they are prone to separation with time, even when stored as microemulsions. It is unknown how the entrained water in the bio-oil would affect the combustion process. However, adding water to the combustion process is a well-known method for lowering PM emissions and, in some cases, even NOx emissions. To directly replace MGO with a biofuel, the production volume of the biofuel must be sufficient to fulfil the demand. Whether current biofuel production can successfully replace MGO is uncertain. However, when used in blends, biofuels provide chances to reduce both PM and CO2 emissions; additionally, as the demand for MGO increases, biofuels may provide a monetary benefit (Hsieh and Felby, 2017).
4. Biomass to Biofuel Conversion Technology Alternative
In the paper, it was already stated that producing profitable biofuels would simultaneously produce higher grade fuels for the aviation industry such as kerosine and other lower grade fuels such as diesel. It is imaginable that the production and selling of the higher-grade fuel could set off the sale of the lower-graded fuel, even if the lower-grade fuel would have to be sold with a loss to be competitive against regular fossil fuels. There are conversion technologies whereby biogenic alcohol is turned into kerosene; these processes are called “Alcohol-to-Jet”-processes (AtJ). Different biochemical and/or thermochemical processes can be used to extract the necessary alcohols from organic materials. Future biofuel production might access a wide range of feedstock sources thanks to the ability of lignocellulosic biomass and organic waste and both sugary and starchy biomass to be transformed into a diluted form of sugar or alcohol using existing equipment as well as future technology. For a number of reasons, several pure alcohols are not suited as maritime fuels to directly use in currently used marine engines without retrofitting them first. Their energy content is substantially lower than typical marine fuels due to alcohol molecules, including oxygen. Moreover, methanol and ethanol have notably different chemical and physical characteristics from regular marine fuels in terms of fixed boiling points (no boiling ranges), the heat of vaporisation, miscibility with water, and solvent nature (Kaltschmitt, 2019). Nevertheless, in theory, all alcohols can be transformed into long-chain hydrocarbons similar to those in regular fuel (Kaltschmitt, 2019). However, because methanol, ethanol, and butanol are commodities sold in large volumes on the global market, fuel producers and process developers have thus far mainly focused on technology-based for these substances (Kaltschmitt, 2019). To produce biofuel from alcohol, biomass is firstly needed. Organic raw materials can produce methanol, ethanol, and butanol (e.g. sugar, starch) (Kaltschmitt and Neuling, 2018). Most thermo-chemical and bio-chemical conversion techniques are utilised during the various production processes. The related conversion routes vary greatly. In the fractionation, the alcohol molecules are transformed into long-chain hydrocarbons once they have been created (Kaltschmitt and Neuling, 2018). For all methods, the fundamental ideas guiding the further processing step are essentially the same and are more or less unaffected by the alcohol previously utilised. Dehydration, oligomerisation, hydrogenation, and distillation are all processes in the conversion process. With AtJ technologies, it would be possible to produce several products, such as ethene, ethane, propene, propane, LPG, gasoline, naphtha, kerosene and diesel, depending on the resource and processes. Regardless, only a few companies are currently pursuing the deployment of AtJ technology. The scale includes anything from small-scale lab facilities to larger pilot plants. The benefits of economies of scale have not yet been fully utilised because no industrial-scale AtJ operations exist. Since AtJ processes are still in the early stages of research, there is a good chance that they can be improved, which could lower production costs. (Hemighaus et al., 2006) Given that it uses a multitude of feedstocks, biofuels produced from alcohol could play a significant role in the future supply of marine fuel (sugary, starchy and lignocellulosic biomass can be used) (Tan et al., 2022). Lignocellulose is particularly relevant in this context since it offers excellent opportunities while simultaneously minimising the potential food vs fuel conflict. Since alcohol can be made from sugar, starch, and lignocellulosic biomass, hemp would be a suitable crop. Hemp fibre can be considered to be lignocellulose. Hemp Hurd is considered starchy, and the hemp root can be considered sugary. Using these parts of the plants, the hemp seeds could still be used as food or feedstock for animals; with that, the food and fuel could be proudest in symbiosis. When the seed is separated from the hemp flower, the flower could still be used as a tea or CBD oil. The topic of hemp as a biomass resource will be handled later in the paper. (Hemighaus et al., 2006)
5. Advantages of Biofuels
* The shipping industry sees biofuels as green energy since biofuels or blends with biofuels have the potential to reduce the air emissions of sulfur oxides (SOx), nitrogen oxides (NOx), and particulate matter (PM) (Andreas, 2020).
* Another advantage is that biofuels are made of renewable resources and can be considered sustainable energy sources (Andreas, 2020).
* The energy unit price from biofuels is low (Andreas, 2020).
* It is expected that there will be a large amount of biomass available on a global scale (Andreas, 2020).
* A crucial fact is establishing local energy production to be more independent from other countries (Andreas, 2020).
* Another thing is that biomass sources are scalable and flexible; the farmers can use them as an intercrop at the end of the season since hemp grows faster. The farmer will not need to set up a solar power system, which will make the land unusable for food production and require a high investment (Andreas, 2020).
* The technology has matured due to extensive research in the past (Andreas, 2020).
* As already said, biomass raw material can be taken from various resources, whereby hemp would be a good alternative compared to commonly used energy crops (Andreas, 2020).
* Biofuel technology is considered to be safe (Andreas, 2020).
* Biofuels have a low level of greenhouse gas emissions (Andreas, 2020).
* The production of biofuels locally will create a whole new sector with new job opportunities, from cultivation, harvesting, supplying, processing, transportation and the typical commercial jobs in a company, like sales, marketing etc. Moreover, when the whole value chain stays in the country, the profits will stay there, too, creating even more job opportunities in the economy (Andreas, 2020).
* Since the energy transition will need to happen fast (Andreas, 2020).
* To stop climate change, the energy transition will need to happen fast, and biofuels will play an essential role in that process. Sectors like wind and solar energy will take time to meet the demand of our economy since they require a large amount of resources, labour force and production time. A critical point of this sector is the shortage of skilled workers to meet the demand. In the meantime, farmers can grow plants right now and then their biomass can be used in already used processes to produce biofuels (Andreas, 2020).
6. Disadvantages of Biofuels
On the other side, there are also supposed disadvantages. For example, it is expected that plants for biomass need a lot of chemical fertilisers, pesticides and water. Since they demand a lot of raw materials and generate a lot of greenhouse gas emissions throughout the entire production process, the manufacture of biofuels can be highly inefficient. The biomass production contributes to deforestation and biodiversity since large land areas are needed, where the biomass crop will be planted in a monoculture to meet the demand. The monoculture without intercrop rotation will wear out the soil, and more fertilisers will need to be used to grow the same crop over and over again. Since there will be residues of the harvest on the field, it is easier for plant diseases and pests to survive on the residues and spread the next time the crop is planted; to suppress those, pesticides and herbicides are used preventive instead of reactive, which will result in high use of such chemicals. The harmfulness of such pesticides is also not limited to pests; some are also harmful to beneficial insects. So, it can be concluded that using such chemicals will result in biodiversity loss, which should be viewed as a negative. Using biomass as fuel will also require a high initial investment throughout the production chain. It is expected that the production of biomass will need a large amount of agricultural land, which otherwise would be used to produce food or feedstock; the result is less land for this purpose, which will increase global food prices, through that create worldwide hunger and starvation. When people cannot buy enough food, citizen coups are also very likely, which then can end up in war and more refugees. Considering the mentioned disadvantages, it is comprehensible that the general public is still sceptical regarding biofuels (Andreas, 2020).
7. Hemp as a Biomass resource
Hemp is not an energy per se, but it contains carbohydrates. Anything produced from hydrocarbons (coal, oil, and natural gas) can be made from carbohydrates (biomass, alcohol, charcoal, fuel oil, methane gas). According to Davis, “Hemp, especially the hurds, can be burned as is or processed into charcoal, methanol, methane, (ethanol or butanol), or gasoline through pyrolysis (destructive distillation) (Davis, 2009). To give a brief summary, growing hemp as biomass reduces land completion between food and biomass crops since hemp has multiple parts: seeds, flowers, hurds, fibres and roots. More than 50.000 products can be made from hemp; for example, the seeds could be used as a food source, the flower as medicine (CBD), the fibre as cloth and more, the roots (for spirits) and the hurds (for construction material or biofuel production). This part of the paper will use the above disadvantages as hypotheses and contrast them with the advantages of biomass from hemp.
One argument was that the crops for biomass production would use a lot of fertilisers and water; Buckley said that hemp has the “ability to grow “like a weed” without requiring lots of water, fertilisers, or high-grade inputs to flourish (Buckley, 2010). It is also mentioned that biomass production will require lots of herbicides; this is not the case with hemp. Hemp overgrows weeds very fast so that the weed does not get enough sunlight and is suppressed in its growth (Alcheikh, 2015). Another point was the use of excessive use of pesticides. A pest outbreak that threatens the harvest is also unlikely when growing hemp. Hemp takes about 90 to 120 days from seed to harvest, which is too short to develop severe pest outbreaks in the crop (Alcheikh, 2015). As mentioned above, experts say the production of biofuels can be pretty inefficient. Still, hemp has “great benefit which considers in its ability to create over 24 tons of biomass per hectare during 140 days, so the use of hemp for energy purposes can be an interesting alternative.” (Havrland et al., 2013, pp.541–544). The disadvantage that biofuels need a large amount of raw materials is true, but when remembering that lots of biofuels in the current state are made from palm oil, hemp has an advantage. To produce palm oil, farmers in Brazil, for instants, clear large fields from the Amazonas rainforest for this agricultural land. If the industry started to use hemp, they would not need clear forest areas to obtain more agricultural land for palm oil production. Furthermore, as already mentioned, hemp can grow on infertile soil, which leaves fertile land for food and forest (Mardan, 2015). The rainforest can then serve as a carbon sink. The argument that significant greenhouse gas emissions exist in the whole production chain can also be dismissed since it is possible to use hemp and other alternative energies throughout the entire production chain. There is another argument that there can be pollution in the production chain. Still, when using hemp as biomass, which at the same time is used for many other purposes, such as food and feedstock, it is doubtful that the biomass will be polluted (Davis, 2009). One of the strongest arguments is that large areas of land are needed for biofuel production, which is true, but what kind of land is another thing. Hemp can grow in infertile soils, which reduces the need to grow it on agricultural land, which is needed for growing food and feedstock (Buckley, 2010). Hemp can also adapt to various soil conditions and grow in multiple environmental conditions (Citterio et al., 2003). Another thing is hemp does not have to be grown in a monoculture, it can be grown as an intercrop, and since it is a fast-growing plant, it can be planted at the end of the season. The timeframe between the maincrop and the end of the growing season can be too short for other plants, whereby enough for hemp (Adesina et al., 2020). Hemp has many benefits as an intercrop; it has long and wide roots, and the taproot grows deep in the ground and breaks it open (Adesina et al., 2020). Hemp also leaves nutrition in the soil, which is suitable for other plants.
Hemp also can absorb heavy metals from the soil. Hemp removes soil contaminants such as chromium, zinc, copper, selenium, cadmium, nickel, lead and dioxin (Citterio et al., 2003).
Metallic toxins are bound through root adsorption and metal precipitation and stabilised through complex formation or decrease in phytostabilisation (Placido and Lee, 2022). Metals are bound and fixed to a nontoxic state within the plant, preventing contact with cellular metabolism (Placido and Lee, 2022). That means the plant can take up soil contaminants through the roots and then be accumulated in the plants’ roots, leaves, shoots and stalks (Angelova et al., 2004). Metal concentrations in the growing environment cause increased accumulations in plant tissue. The contaminated leaves and shoots cannot be used for food or other purposes, so they are disposed of with various methods, such as heat and extraction treatments (Liu and Tran, 2021). One option would be to incinerate the plant material as hazardous waste and dispose the ash on landfills (Keller et al., 2005) or use methods to re-extract the trace elements (McGrath, Zhao and Lombi, 2002). The stalks can be used in building materials, paper, cloth and biofuel production (Placido and Lee, 2022). The seeds can be used to produce biofuels as well. Hemp has been cultivated in Chernobyl since 1998, where it removed soil contaminants from the soil, which was heavily contaminated through the nuclear disaster in Chernobyl in 1986 (Charkowski, 1998). Hemp can also remove contaminates from soil, as Placido and Lee stated: “In 2008, in an Italian farming region contaminated by a nearby steel plant, hemp was grown to leach pollutants, such as dioxin, from the soil. Dioxins are toxic as they cause cancer, affect reproduction and development, damage the immune system, and interfere with hormones. Once remediation is complete, plant material containing dioxins can be used to produce energy. Beyond cleaning soil, research is being conducted on using hemp fibres to absorb material capable of filtering out metals from contaminated water” (Placido and Lee, 2022). Right now, most biodiesel comes from palm oil, switchgrass, and waste vegetable and animal fats, which contributes to deforestation, and that is why biofuels have a terrible reputation. Since hemp does not need to grow on fertile land, forest areas can stay untouched. Another thing is that paper and cardboard are made from woody cellulose, as paper and cardboard can be made from hemp cellulose as well, and hemp grows faster than trees; therefore, the cultivation of hemp could also reduce deforestation. The cultivation of soybeans also requires lots of land, which is gained through fire clearing of part of the Amazonas and because hemp can also be used as a food and feedstock source, the deforestation of such areas will also be reduced. The concern that biodiversity is loosed by growing energy crops is there, but the matter can be dismissed when growing the energy crops as intercrop in intercrop cultivation. Another concern is that high initial investments are required, but because there is already a hemp industry, a hemp biofuels sector would require little new investment (Buckley, 2010). An essential point regarding biofuels is using agricultural land for biomass production instead of food or feedstock. The increased biofuel consumption would also increase the demand for agricultural land to produce the biomass. If the agricultural land is used for biomass production, the land used to grow food crops would be reduced, whereby a decrease in food supply and an increase in global food prices would be the result. Increasing global food prices would create worldwide hunger and starvation since many people will have a problem paying the higher prices. The following would be a citizen uprising and war, and more refugees. Another issue related to the world’s food is the lack of enough protein sources to feed the whole world properly. When hemp is used as biomass, the conflict between biofuels and food would be reduced since the hemp plant has multiple parts, which can be processed for various purposes; one would be the use of hemp seed as food and feedstock. A big problem is the lack of protein, which causes malnutrition worldwide and slows development and learning. Hemp has benefits as biomass for biofuel production and is also a good food source. First and foremost, Hemp seeds are a rich source of healthy essential fatty acids. The ratio of the essential fatty acids in hemp seeds is 3:1 of omega-6 to omega-3, which study has shown to be a ratio that contributes to human health. Also, Hemp seeds have lots of protein; to be exact 25% of their nutrition comes from protein. That is not all. Hemp seeds contain all the essential amino acids, making them a complete protein source, which is not commonly found in plant-based protein sources. Hemp seeds are also a great source of micronutrition, such as fibre, vitamin E, phosphorus, potassium, sodium, magnesium, sulfur, calcium, iron, zinc, arginine and gamma-linolenic acid. All these micronutrition have different kinds of benefits for the human health (Bjarnadottir, 2018). The last argument against biofuels is that the general public is still sceptic regarding biofuels (Andreas, 2020); when considering all the mentioned advantages of hemp and making them known to the public, with quite a certainty, all these sceptics will disappear.
The paper discussed the topic of decarbonisation of the maritime industry, biofuels for the transition phase and future, biomass to biofuel conversion technology alternative, and the advantages and disadvantages of biofuels and hemp as a biomass resource. The shipping industry aims to reduce its emissions to comply with the regulations and other legislation such as the Paris agreement and the European green deal. The paper discussed biofuels’ use in the transition phase and the future. The section also discussed the infrastructure & storage, energy density, technology maturity, green credentials, independency, availability, flexibility, cost and qualities and characteristics. The conclusion for this part of the paper is that the current infrastructure and storage facilities can directly be used for biofuels without retrofitting them. This gives biofuels an advantage over other alternative fuels. Regarding energy density, biofuels also have an advantage since their energy density (energy per volume) is denser than other alternative fuels., which means that the current fuel tanks can be used directly, whereby the fuel tanks would have to be retrofitted or there even would have to be made new instalments to accommodate the alternative fuels. Biofuel production technology is also more mature than other alternative fuels since it has a long history of development and, in some way, is already utilities a long time. Biofuels have also green credentials is also given, in many ways. First of all, biofuels have lower sulfur and nitrogen content and consequently produce lower emissions of sulfur oxides (SOx), nitrogen oxide (NOx) and particulate matter (PM) (Placido and Lee, 2022), which is an environmental benefit and contribute to improved air quality. Thus, the improved air quality also does not harm human health like the combustion of fossil fuels. Another point is that the carbon released is harvested from the atmosphere during the cultivation of the biomass, so it is a cycled system. Biofuels made from plants or other organisms are fast biodegradable, presenting much less of a hazard to the marine environment than other fuel options. Another advantage of biofuels is that they can be blended with current fuels. When marine fuels are blended with biofuels, the energy needed to reach the optimal viscoelasticity can be decreased, which means that the energy required to heat and process traditional marine fuel oil before fuel injection can be reduced. With that, vessels’ energy efficiency (and CO2 emissions) can be improved. Compared to other alternative fuels, the same cannot be done since some can’t be blended but instead have to be used as single fuel. Biofuels also increase the independence of nations and their economy. Producing biomass locally lets the revenue remain in the country instead of being sent to other parts of the world. Growing biomass has the potential to assist us in developing our way out of the current economic crisis and would contribute to the overall health of society. Regarding the availability of biofuels, it can be said that the current engines would run with biofuels, and the existing marine fuel supply chain can be used for biofuels. The problem with the availability is the economy of scale since there is not enough biofuel to replace the current marine fuel. Right now, it could be used as a blend-in with existing marine fuels or in limited quantities near the coast and inland waterways, but not for deep-sea vessels. Biofuels would make much sense near highly populated areas to reduce the air emissions in the environment without needing new vessels or retrofitted engines. The flexibility of biomass is also better than alternative fuels since the supply can be adjusted to the demand as in chapter 3.7 Flexibility of this paper is described. Regarding the cost of biofuels, the paper illustrated that biofuel has to compete against regular marine fuels, which will be difficult in the short run (Kaltschmitt and Neuling, 2018). If, in the long run, stricter regulations and laws regarding fuels and exhaust gases are set in place, biofuels can become competitive (Kaltschmitt and Neuling, 2018). Also, when biofuel production technologies become more cost-efficient, they would have the potential to compete against other fuels. Another option would be to produce higher and lower graded fuel simultaneously, whereby the higher graded fuel would offset the potential loss of selling the lower grade marine biofuel at a competitive market price. One way to do that could be to utilise “Alcohol-to-Jet” processes to produce higher-grade fuel such as kerosene and lower-grade fuel such as diesel simultaneously, as described in chapter 4. Biomass to Biofuel Conversion Technology Alternative. There could be potential further research on how biofuel could be produced cost-efficient for different industries simultaneously. In chapter 6, the disadvantages of biofuels were described and, at the same time, dismissed with the advantages of the hemp plant. The introduction of hemp as a biomass resource could solve most problems regarding the competition between biomass and food production. Furthermore, the hemp plant as biomass could solve additional issues discussed in the chapter. However, further research is needed to clarify if hemp as a biomass crop could solve the mentioned problems.
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