Electrofuels: a review of pathways and production costs

Electrofuels are produced from carbon dioxide (CO2) and water using electricity as the primary source of energy. Production costs for the fuel options methane, methanol, dimethyl ether, Fischer-Tropsch (FT) diesel are estimated based on different assumptions. The production costs of these electrofuels, for a best, average and worst case, was found to be in the range of 120-135, 200-230 and 650-770 €2015/MWh fuel respectively where methane had the lowest and FT diesel the highest costs within each range

The Potential Role of Ammonia as Marine Fuel-Based on Energy Systems Modeling and Multi-Criteria Decision Analysis

To reduce the climate impact of shipping, the introduction of alternative fuels is required. There is a range of different marine fuel options but ammonia, a potential zero carbon fuel, has recently received a lot of attention. The purpose of this paper is to assess the prospects for ammonia as a future fuel for the shipping sector in relation to other marine fuels. The assessment is based on a synthesis of knowledge in combination with: (i) energy systems modeling including the cost-effectiveness of ammonia as marine fuel in relation to other fuels for reaching global climate targets; and (ii) a multi-criteria decision analysis (MCDA) approach ranking marine fuel options while considering estimated fuel performance and the importance of criteria based on maritime stakeholder preferences. In the long-term and to reach global GHG reduction, the energy systems modeled indicate that the use of hydrogen represents a more cost-effective marine fuel option than ammonia. However, in the MCDA covering more aspects, we find that ammonia may be almost as interesting for shipping related stakeholders as hydrogen and various biomass-based fuels. Ammonia may to some extent be an interesting future marine fuel option, but many issues remain to be solved before large-scale introduction

Criteria and Decision Support for A Sustainable Choice of Alternative Marine Fuels

To reach the International Maritime Organization, IMO, vision of a 50% greenhouse gas (GHG) emission reduction by 2050, there is a need for action. Good decision support is needed for decisions on fuel and energy conversion systems due to the complexity. This paper aims to get an overview of the criteria types included in present assessments of future marine fuels, to evaluate these and to highlight the most important criteria. This is done using a literature review of selected scientific articles and reports and the authors’ own insights from assessing marine fuels. There are different views regarding the goal of fuel change, what fuel names to use as well as regarding the criteria to assess, which therefore vary in the literature. Quite a few articles and reports include a comparison of several alternative fuels. To promote a transition to fuels with significant GHG reduction potential, it is crucial to apply a life cycle perspective and to assess fuel options in a multicriteria perspective. The recommended minimum set of criteria to consider when evaluating future marine fuels differ somewhat between fuels that can be used in existing ships and fuels that can be used in new types of propulsion system

Organic Cultivation of Lemon Ballm (Melissa officinalis) in Macedonia

The possibility for perspective growing of medicinal, aromatic and spice plants, can be expected only if their cultivation is based on the principles of organic farming. The cultivation of this group of plants is usually associated with satisfactory yield level and raw materials with uniform quality. This paper contains the most important features of lemon balm (Melissa officinalis), and methods of cultivation. Data of two annual activities are presented and they are related with organic system of cultivation in the central part of Macedonia. The objective of this study is to analyze, determine and demonstrate the economic viability of lemon balm organic production with irrigation. In the first year, there were only two moving, yielding 500 kg/ha of above-ground plant dry mass. In the second year, there were three moving, yielding 6,775 kg/ha of above-ground plant dry mass. Economic analysis is proved that profitability in organically produced lemon balm is obtained in the second year of growing when the profit reached $6,150/ha. Key words: Organic, lemon balm, yield, pofitability

Reviewing the development of alternative aviation fuels and aircraft propulsion systems

Alternative aviation fuels such as bio-jet fuels, liquid natural gas (LCH4), hydrogen (H2), electro-jet fuels and direct electricity use play an important role in decarbonizing the aviation sector. New aircraft propulsion systems are being developed but low-blending of fuels is possible for some options. It is imperative to understand the technical, environmental and economic performance of the different alternative aviation fuels and the new engine and propulsion technologies for the utilization of these fuels. We have reviewed various literature to map the current status of development on alternative aviation fuels and related aircraft propulsion systems in relation to different perspective such as their cost and technical maturity. There are several challenges related to the design and implementation of the fuels and new propulsion systems. For instance, the volumetric energy content of alternative fuels is lower than the conventional aviation fuels which requires larger fuel storage tanks. Despite the advantageous environmental performance, both the bio-jet and electro-jet fuels are currently not economically competitive. Yet, studies forecast that increased use of alternative aviation fuels is possible after modifications of engines, fuel storage tanks and improvements of the aerodynamics of aircraft and by introducing subsidies and/or carbon taxes on conventional jet fuels

Life-Cycle Assessment and Costing of Fuels and Propulsion Systems in Future Fossil-Free Shipping

Future ships need to operate with low or possibly zero greenhouse gas (GHG) emissions while ensuring low influence on other environmental impacts and that the operation is economically feasible. This study conducts a life-cycle evaluation of potential decarbonization solutions involving selected energy carriers (electrolytic hydrogen, electro-ammonia, electro-methanol, and electricity) in different propulsion system setups (engines, fuel cells, and carbon capture technologies) in terms of environmental impact and costs. The results of the study show that the assessed decarbonization options are promising measures to reduce maritime GHG emissions with low-carbon-intensive electricity. The same order of GHG reduction is shown to be possible independent of the propulsion system and energy carrier used onboard, However, the carbon abatement cost ranges from 300 to 550 (sic)/tCO(2)eq, and there is a trade-off with environmental impacts such as human toxicity (cancer and non-cancer effects) and freshwater ecotoxicity mainly linked with the wind infrastructure used for electricity production, Electro-ammonia in fuel cells is indicated to be effective in terms of the carbon abatement cost followed by the so-called HyMethShip concept. The higher abatement cost of all options compared to current options indicates that major incentives and policy measures are required to promote the introduction of alternative fuel and propulsion systems

How do variations in ship operation impact the techno-economic feasibility and environmental performance of fossil-free fuels? A life cycle study

Identifying an obvious non-fossil fuel solution for all ship types for meeting the greenhouse gas reduction target in shipping is challenging. This paper evaluates the technical viability, environmental impacts, and economic feasibility of different energy carriers for three case vessels of different ship types: a RoPax ferry, a tanker, and a service vessel. The energy carriers examined include battery-electric and three electro-fuels (hydrogen, methanol, and ammonia) which are used in combination with engines and fuel cells. Three methods are used: preliminary ship design feasibility, life cycle assessment, and life cycle costing. The results showed that battery-electric and compressed hydrogen options are not viable for some ships due to insufficient available onboard space for energy storage needed for the vessel\u27s operational range. The global warming reduction potential is shown to depend on the ship type. This reduction potential of assessed options changes also with changes in the carbon intensity of the electricity mix. Life cycle costing results shows that the use of ammonia and methanol in engines has the lowest life cycle cost for all studied case vessels. However, the higher energy conversion losses of these systems make them more vulnerable to fluctuations in the price of electricity. Also, these options have higher environmental impacts on categories like human toxicity, resource use (minerals and metals), and water use. Fuel cells and batteries are not as cost-competitive for the case vessels because of their higher upfront costs and shorter lifetimes. However, these alternatives are less expensive than alternatives with internal combustion engines in the case of higher utilization rates and fuel costs

Alternative marine fuels: Prospects based on multi-criteria decision analysis involving Swedish stakeholders

There is a need for alternative marine fuels in order to reduce the environmental and climate impacts of shipping, in the short and long term. This study assesses the prospects for seven alternative fuels for the shipping sector in 2030, including biofuels, by applying a multi-criteria decision analysis approach that is based on the estimated fuel performance and on input from a panel of maritime stakeholders and by considering, explicitly, the influence of stakeholder preferences. Seven alternative marine fuels—liquefied natural gas (LNG), liquefied biogas (LBG), methanol from natural gas, renewable methanol, hydrogen for fuel cells produced from (i) natural gas or (ii) electrolysis based on renewable electricity, and hydrotreated vegetable oil (HVO)—and heavy fuel oil (HFO) as benchmark are included and ranked by ten performance criteria and their relative importance. The criteria cover economic, environmental, technical, and social aspects. Stakeholder group preferences (i.e., the relative importance groups assign to the criteria) influence the ranking of these options. For ship-owners, fuel producers, and engine manufacturers, economic criteria, in particular the fuel price, are the most important. These groups rank LNG and HFO the highest, followed by fossil methanol, and then various biofuels (LBG, renewable methanol, and HVO). Meanwhile, representatives from Swedish government authorities prioritize environmental criteria, specifically GHG emissions, and social criteria, specifically the potential to meet regulations, ranking renewable hydrogen the highest, followed by renewable methanol, and then HVO. Policy initiatives are needed to promote the introduction of renewable marine fuels

A COMPARATIVE ASSESSMENT OF CURRENT AND FUTURE FUELS FOR THE TRANSPORT SECTOR

To facilitate the transition to a sustainable and less fossil dependent transport sector in the short to medium term, the current fuel mix needs to be enriched with renewable fuel alternatives. The present work aims to assess and highlight the opportunities for current and future biomass based fuels to be utilized. Seven fuels and fuel blends fulfilling the EN590 diesel fuel standard have been selected and are compared using qualitative and quantitative criteria covering technical, environmental and economic attributes of the fuels. Mature fuels such as dimethyl-ether (DME) and hydrotreated vegetable oils (HVO) are ranked higher in the assessment due to the increased possibility for environmental gains at moderate costs. For future fuels to be competitive stricter regulation in terms of GHG emissions savings are needed

Review of electrofuel feasibility - Prospects for road, ocean, and air transport

To meet climate targets the emissions of greenhouse gases from transport need to be reduced considerably. Electrofuels (e-fuels) produced from low-CO2 electricity, water, and carbon (or nitrogen) are potential low-climate-impact transportation fuels. The purpose of this review is to provide a technoeconomic assessment of the feasibility and potential of e-fuels for road, ocean, and air transport. The assessment is based on a review of publications discussing e-fuels for one or more transport modes. For each transport mode, (a) e-fuel options are mapped, (b) cost per transport unit (e.g. vehicle km) and carbon abatement costs are estimated and compared to conventional options, (c) prospects and challenges are highlighted, and (d) policy context is described. Carbon abatement costs for e-fuels (considering vehicle cost, fuel production and distribution cost) are estimated to be in the range 110-1250 € tonne-1 CO2 with e-gasoline and e-diesel at the high end of the range. The investigated combined biofuel and e-fuels production pathways (based on forest residues and waste) are more cost-competitive than the stand-alone e-fuel production pathways, but the global availability of sustainable biomass is limited making these pathways more constrained. While the potential for e-fuels to decarbonize the transport sector has been discussed extensively in the literature, many uncertainties in terms of production costs, vehicle costs and environmental performance remain. It is too early to rule out or strongly promote particular e-fuels for different transport modes. For e-fuels to play a significant role in transportation, their attractiveness relative to other transport options needs to be improved. Incentives will be needed for e-fuels to be cost-effective and increased clarity on how e-fuels are linked to existing policies is needed