Dear user of the Technology Data Catalogues. This newsletter dives into the latest chapter describing production of green ammonia.

If you are new to the topic of Technology Data, you can always learn more and find the latest available versions of the Danish Technology Catalogues here. You can find all published newsletters here. You can also find our anticipated work plan at the end of the newsletter.

The latest additions to our comprehensive dataset are the chapters on:

1. Production of green ammonia based on green hydrogen as input
2. Transport of gas and liquid fuels including data sheets of the pipeline transport of hydrogen at 70 and 140 bar pressure levels, ammonia, DME and liquid hydrocarbons (including LOHC), as well as road and ship transport.

The newsletter covers some more detailed information from the chapter on production of green ammonia, which can be found here, being part of the Technology Data Catalogue for Renewable Fuels.

The chapter gives an overview of different pathways for production of ammonia based on grey, blue and green hydrogen respectively, as shown in the chapter’s overview schematic below in Figure 1, plus a short outlook on a future electrochemical pathway via co-electrolysis. More explanation regarding the different pathways shown in the figure can be found in the chapter itself.

Figure 1: Different pathways for production of NH3. The light green area is the green NH3 production part that is covered within this Technology Catalogue. The darker green area marks a potential future route (electrochemical). The white background shows the three conventional parts, i.e. 1a) Steam Methane Reforming (SMR) +Air Separation Unit (ASU), 1b) SMR+secondary reformer (2.REF) and 2) autothermal reformer (ATR)+ASU.

Besides the usual content of the Technology Data Catalogue chapters, you can also find further discussions of integration possibilities of ammonia plants and possibilities for flexible operation in the publication.

The demand for operation flexibility highly depends on the input feed of the plant (either hydrogen or power) and requirements on the product flow. Constructing an ammonia plant close to a hydrogen transmission net will ensure a stable feed flow through the hydrogen buffer stemming from the transmission net. On the other hand, if hydrogen is produced onsite through electrolysis and thus with the input of power, fluctuating power prices and the interest to maximize production will lead to the following considerations for the plant:

1. Design NH₃ plant with a large operation range and additional ammonia storage:
   The additional storage is to ensure NH₃ supply demand when power-prices are high. NH₃ plant can typically be designed with a minimum operation ratio of 20-25% with minor additional cost. Additionally, it can be kept in a hot standby mode for several days without additional CAPEX spending. The optimal storage capacity should be balanced between the cost of additional storage and the high marginal ammonia production cost during high power prices.
   
   
2. Constructing a hybrid ammonia plant with buffer conventional production:
   The reforming section of the conventional plant section can run in times of high powerprices complementing the production of green ammonia, but the ammonia production will entail greenhouse gas emissions in the process.

In the longer run, it is expected that the expansion of a hydrogen transmission net will make the two considerations less important and ensure a stable production of ammonia through the buffer the grid supplies. This will also accommodate the usual requirement of an ammonia plant to run at base load, since the significant investment cost and the payback time of the plants initial expenses economically calls for this type of operation.

Usage of the cost data in the datasheet:

Even though there are only few operational plants in the world producing green ammonia, this energy carrier is expected to play a major role in maritime shipping and as feedstock for green fertilizers. The ammonia market is therefore anticipated to get a significant boost in the coming years. Since the synthesis of ammonia through the chemical Haber-Bosch process is well known, the conversion process from hydrogen to ammonia is considered very mature with limited potential for improvement. Technological improvement is mainly thought to stem from electrolysis and the production of green hydrogen. The main source for cost reductions for the production of ammonia is therefore associated with improvement of the electrolysis (both capital cost and efficiency), and via economy of scale aspects concerning the ammonia synthesis plant.

The datasheets accounts for economy of scale by assuming an increase in capacity throughout the years as representative plants. In the shorter run, there are, however, also prospects for larger plants than what follows the representative trend in the datasheet.

Consequently, in order to reflect appropriate cost assumptions for large plants, a cost curve shown in the chapter directly links the cost data to its respective plant size. If one wants to take cost data for a e.g. 500 MW (ca. 2290 MTPD [metric tons per day]) ammonia output plant for whichever year, one should use this data regardless of which year the plant is thought to be established (even though this represents the cost data for a representative plant in 2050 in the datasheet).

As the economy of scale has a higher impact on the cost of the ammonia plant than the limited cost reduction potential through learning and development over time, using the cost data in this intended way will improve your analysis.

Figure 2: Estimated cost of ammonia synthesis + Balance of plant + Storage (electrolysis unit and ASU is not included in the figure). Blue triangles represent data that is publicly available. All figures adjusted to reflect cost index for 2019.

The realisation of a complete Power-to-X value chain will most often involve transportation of hydrogen and other synthetically produced energy carriers. The Power-to-X facilities will not always be located close to generation clusters of renewable power, nor will they necessarily be located close to consumption centres. The grid and transport infrastructure is a crucial part of describing the whole business case. 

To be able to extend the analysis scope beyond only production aspects, the chapter on production of green ammonia is complemented by a dedicated chapter on transport of ammonia and other Power-to-X energy carriers hydrogen, DME and liquid hydrocarbons, which can be found here, being part of the Technology Data Catalogue for Energy Transport and CO₂.

Together with the updated and consolidated chapter on production of hydrogen through electrolysis, which will be published soon, the Technology Data Catalogue comprises up-to-date qualitative and quantitative data for all main elements of Power to X in terms of production, transport and storage.

News and updates completed 1/2021 - 3/2021

Future updates (list may be expanded)

Best regards,
The Technology Data Catalogue team