This study compares two production pathways for ammonia with low sulphur fuel oil (VLSFO) used as fuel in shipping. The ammonia is produced through the Haber‐Bosch process, where nitrogen (N2) and hydrogen (H2) are combined into NH3. The main difference between the two ammonia production pathways lies in the H2 production, as the H2 can be from natural gas (CH4) in combination with carbon capture and storage (CCS) or via electrolysis of water (H2O) with renewable electricity sources. Within the industry, the two pathways are often called ‘blue’ and ‘green’ ammonia.
Ammonia must be ignited by a pilot fuel, which is assumed to be VLSFO, and the study therefore compares 1 MJ of ammonia, where VLSFO accounts for 9.6% of the total fuel energy of 1 MJ ammonia, with 1 MJ of VLSFO. Throughout the report, the share of VLSFO as a pilot fuel needed to ignite ammoni a is referred to as ‘ammonia with 9.6% e/e VLSFO’.
The LCA includes all life cycle stages from cradle to grave of ammonia fuel and VLSFO, i.e., production of fuel feedstock, fuel production, distribution and bunkering, as well as storage and combustion on board of the ship. This system boundary is often referred to as ‘well-to-wake’ (WtW).
The report includes two modelling approach: a consequential model and an attributional model aligned with the revised version of the Renewable Energy Directive (RED II) guidelines for renewable fuels of non-biological origin (RFNBOs).
This report is commissioned by A.P. Moller – Maersk and internal quality assurance has been ensured by inviting several relevant stakeholders to take part in the project scoping, data collection, and review of methods and assumptions. While the partners have contributed to validating the technical aspects, they have not participated in the interpretation of the results.
The project partners include: A.P. Moller – Maersk, Environmental Defense Fund Europe, Nippon Yusen Kabushiki Kaisha, CMA CGM, DFDS A/S, American Bureau of Shipping, MAN Energy Solutions, Svitzer A/S and Havenbedrijf Rotterdam N.V.
Appendix 9 – Marginal electricity mixes
Appendix 11 – Final review statement and itemized review report
Download full report here:
We helped B’ZEOS compare the environmental impact of their seaweed packaging solution by analyzing the cradle to grave impact of their product and compare it with other biobased and fossil fuel based solutions on the market. Project completed October 2024.B'ZEOS wanted to know how their product design performed against their competitors and know more about how the choice of input materials affected the overall environmental impact of their product.
The study constituted a prospective LCA of a packaging solution currently under development by the company, produced from seaweed extracts. This was then compared, on a cradle-to-grave basis, to equivalent products based on other petrochemical and bio-based materials available on the market. The results allowed B’ZEOS to not only benchmark the environmental performance of their product against potential competitors, but also to gain insights as to how to improve this performance regarding aspects such as product design, choice of raw materials and implications in terms of product disposal at the end of its useful life.
Our collaboration with Arla began in 2011 with a carbon footprint of Arla’s milk production in Denmark and Sweden. This work has since expanded and been updated through several iterations into an advanced dairy LCA model. Arla uses this model for baselines and benchmarks of its sustainability goals, as well as a tool for individual farmers to understand where their emissions originate.
Today, the dairy LCA model powers Arla’s FarmAhead™ Check tool, which enables 7,986 farmers across seven European countries to calculate the exact GHG footprint of 1 kg of raw milk from their specific farm.
The tool accounts for over 200 farm inputs, including cow feed, fertiliser use, cattle breeds, manure treatment technologies such as biogas, and energy and fuel consumption. These inputs are combined in the LCA model to produce a farm-specific carbon footprint of the milk.
We continuously update and maintain the LCA model to improve the level of detail in the background data and models, as well as incorporating the best techniques for mitigating GHG emissions in milk production.
This design offers Arla full transparency and data autonomy.
The FarmAhead™ Check tool allows Arla to monitor the progress of its climate strategy and assist farmers in reducing emissions by spotting the most effective reductions.
81% of Arla’s total corporate emissions come from its farmers,[1] and the LCA tool provides unprecedented data transparency into where the emissions originate and how top-performing farmers can lead the way for others to do the same.
By 2022, 99% of Arla’s owner milk volume had been assessed by the FarmAhead™ Check tool. The tool makes it possible for Arla to create a data driven and personalised action plan for each farmer to reduce their climate footprint even further.
Our model includes new GHG mitigation technologies as they become relevant for the farmers, including manure acidification and nitrification inhibitors.
[1] https://www.arla.com/49b894/globalassets/arla-global/sustainability/climate-ambition/arla-climate-ambitions-2030-and-2050-2023.pdf p. 7
Energy and non-energy use of fossil carbon-based fuels and associated emissions have been extensively studied, but the retention and accumulation of fossil carbon in the technosphere are less understood. This study uses retrospective dynamic material flow modeling to map the flows related to fossil carbon in durables between the years 1995 and 2019 using monetary multi-regional supply-use tables for 1995–2019 and multi-regional hybrid supply-use tables for 2011. In 2011, 91% of the extracted fossil carbon flowed directly to the atmosphere, with 9% accumulating in the technosphere, primarily in con struction, manufacturing, and households. From 1995 to 2019, 8.4 Gt of fossil carbon (i.e., 30.8 Gt of CO2 equiv) accumulated in all human-made artifacts, with most remaining in use and some ending up in landfills, where decomposition exceeds 50 years. This study lays a critical foundation for future research focused on reducing fossil carbon reliance by curbing its inflow and slowing its throughput in the technosphere.
Hydrogen is widely recognized as an important future energy carrier because of its potential as a less polluting energy source with lower greenhouse gas (GHG) emissions. Several studies however have raised the issue, that a hydrogen economy would could impact the global climate system, by increasing the level of atmospheric hydrogen through leakages and due to the fact that hydrogen has been found to be an “indirect” GHG. This report provides a review of the latest technical and scientific knowledge on leakage rates in current and future hydrogen supply chains, as well as the global warming potential (GWP) of these emissions.
Various regional and international standards have been developed to measure the environmental impacts of transportation fuels and minimize greenwashing and misinformation regarding their sustainability. These frameworks offer standardized methods and calculation guidelines for fuel producers to be able to verify compliance with predefined sustainability criteria and to achieve greenhouse gas emission reduction targets.
However, significant inconsistencies exist among these standards in terms of methods, calculation rules, and default values assigned to specific fuels.
This study reviews and analyses five fuel standards, namely the European Renewable Energy Directive, the United Nation’s Carbon Offsetting and Reduction Scheme for International Aviation, the California Low Carbon Fuel Standard, the United States Renewable Fuel Standard, and the UK Renewable Transport Fuel Obligation. A qualitative analysis of the different schemes’ methods identified several discrepancies.
Overall, our findings demonstrate substantial variations in the methods and calculation rules prescribed by the five standards, often resulting in markedly different carbon intensity scores for the same fuel. Based on this analysis, we propose specific changes to the calculation rules to enhance harmonization and improve the accuracy in reflecting the environmental consequences of fuel production and use. These recommendations include that indirect land use changes are always included, and more transparency regarding the methods for calculating the fuel carbon footprint.
Greenhouse-gas emission (GHG) metric values for methane in the sixth assessment report by the Intergovernmental Panel on Climate Change (IPCC) include the indirect effect associated to the oxidation of methane to CO2. An analysis of the figures provided by the IPCC reveals they assume that in average 75% of methane is ultimately oxidized to CO2, while the remaining 25% is converted to intermediate degradation products, most notably formaldehyde, which are removed from the atmosphere via wet and dry deposition and treated by the IPCC as a potential carbon sink in terrestrial and aquatic ecosystems. In this short article we present a critique to this assumption, based on existing knowledge about the environmental fate of methane's degradation products. We conclude that any assumption other than full degradation of methane to CO2 in a rather short time frame is questionable, whereby the default CO2 yield from this oxidation, as far as GHG metrics are concerned, should be 100%. We re-calculate values for the global warming potential (GWP) metric in accordance with our findings, resulting in an increase in GWP100 from 29.8 and 27.0 to 30.40 and 27.65 kg CO2-equivalents/kg fossil and biogenic methane, respectively. Although we only present the implications in terms GWP, our proposal is conceptually valid for other GHG metrics as well.
The aim of the bonsai_ipcc Python package is to enable users to calculate national greenhouse gas (GHG) inventories based on the guidelines provided by the International Panel on Climate Change (IPCC) (Intergovernmental Panel on Climate Change, 2023). In implementing the equations and parameter data from these guidelines, the package adheres to the organizational structure outlined in the guidelines’ PDF documents, which include volumes and chapters. The package allows users to add their own data. In addition to computing default GHG inventories, the software includes tools for error propagation calculation, such as analytical error propagation and Monte Carlo simulation, both of which are endorsed by the IPCC reports.
Many life cycle assessments (LCA) studies on wooden buildings show potential to decarbonise the building industry, though often neglecting to consider the systemic changes of such a shift at the building stock scale. This study applies a consequential LCA to evaluate the transition from conventional construction to increased wood-based construction in Denmark from 2022 to 2050. The assessment models a material flow analysis of the two construction scenarios, incorporating an area forecast and case buildings. By that, we assessed suppliers' capacity to likely meet the demand for wood, steel, and concrete, employed an input-output model to enhance completeness and country representativeness for other materials' markets, and considered the competition for land by indirect land use change. We implemented a dynamic IPCC-based assessment of GHG-emissions concurrently with a carbon forest model to anticipate the relationship between the delayed carbon storage resulting from using wood in buildings and forest regrowth management. The findings indicate wood construction is the most climate-friendly option for multifamily houses. In contrast, single-family houses (SFH) and office buildings (OB) exhibit the lowest climate impacts in the conventional scenario. The SFH result could be credible due to the sizable GWP impact gap between construction scenarios despite uncertainties related to the weight proportion of sedum roofs. The less conclusive OB findings relate to the substantial steel quantities in the wood case buildings, requiring further investigation. Generally, metals, cement-based- and biobased materials demonstrate the largest climate impact among the material categories. Across all three building typologies, the change to timber construction increased the impact on nature occupation (biodiversity). In conclusion, this study emphasises the need for further research on forest management model inputs, land use change approaches, potential steel suppliers' impact, and a broader array of case studies. It is because these are influential factors in facilitating informed decision-making of the increased implementation of wood in buildings. As the first study to integrate these modelling characteristics, it contributes to the research gap concerning geographical circumstances, forestry, and markets relevant to decision support for increased wood utilisation in Europe's building industry.
This initial study of environmental impacts by continuing current conventional building practices and by changing to increased use of wood is in Danish but has a 5 page illustrated summary in English.
