Prof. Dr. Thorsten Jungmann (last updated 2026-10-20)
Relates to FTS-03 Weighing up, citing and designing your poster
Task
In FTS-03, chapter 1, you have learnt how to weigh up three answers into a balanced, reflective answer. In this exercise, you practise it on our example question from FTS-01 and FTS-02, ‘Does hydrogen make steel production climate-neutral?’, before you weigh up the answers to your own question. Below, you find the three answers: the example of your own answer, passages from the answer of the artificial intelligence (AI) and your notes from the scientific source. Work through the three tasks one after the other; the solution is below each task.
Your own answer – the example from FTS-02, 5.2:
Your own answer
‘I think so, because when hydrogen reacts, only water is produced. I know that steelworks today use a lot of coal and emit a lot of carbon dioxide. I assume that hydrogen could replace the coal and so remove most of these emissions. But I do not know where the hydrogen comes from and how much energy its production needs. I am also not sure whether a steelworks needs other materials that cause emissions.’
The AI answer – the short answer and four passages on the emissions of carbon dioxide (CO₂) and on the electricity needed, from the answer of Claude; the question was put to it word for word, and the answer names no sources (FTS-03, 4.2):
Claude
Short answer – ‘Not by itself. Hydrogen can make steel production nearly climate-neutral, but only if certain conditions are met, and some emissions remain.’
A – on the blast furnace route: ‘This route emits roughly 2 t of CO₂ per tonne of steel, and the steel industry as a whole accounts for around 7–9 % of global CO₂ emissions.’
B – ‘Electrolysis and the arc furnace together need roughly 3–4 MWh per tonne of steel, mostly for producing the hydrogen. Running this on a fossil-heavy grid can make the overall balance worse than today’s route.’
C – ‘Graphite electrodes in the arc furnace burn off and release CO₂.’
D – ‘Carbon in the product: steel is an iron–carbon alloy, so some carbon has to be added, often from fossil sources.’
(Claude, Claude app for macOS, Claude Opus 5.5 with effort xhigh, queried 2026-10-16) – AI output, quoted as an example – not evidence.
The scientific answer – eight notes on the scientific source of our example, written the way FTS-02, 5.4 shows for step 4:
Your notes from the scientific source
- On the blast furnace route, the energy comes mainly from coal and coke (Vogl et al. 2018, p. 739), and the route emits 1 870 kg of CO₂ per tonne of liquid steel (ibid., p. 740).
- Industry as a whole causes 31 % of the global CO₂ emissions, and the steel industry is one of its two largest single contributors (ibid., p. 736).
- The electrolyser splits water into hydrogen and oxygen; the hydrogen then reduces the iron ore to iron in the shaft, and water is formed (ibid., p. 738).
- For one tonne of liquid steel, steelmaking by hydrogen direct reduction takes 3.48 MWh of electricity (ibid., p. 736); the electrolyser uses two thirds of it (ibid., p. 739).
- With renewable electricity, the process has essentially zero emissions (ibid., p. 736). With a power grid that emits more than 532 kg of CO₂ per megawatt-hour, it emits more than the blast furnace route if no scrap is used (ibid., p. 740).
- Even with zero-emission electricity, CO₂ remains, for example from mining iron ore and limestone, from making lime and from the carbon that steel needs (ibid., p. 740).
- In the electric arc furnace, CO₂ comes from lime, from the graphite electrodes and from the carbon that is added (ibid., p. 738). Together, these cause 53 kg of CO₂ per tonne of steel – that is 2.8 % of the emissions of the blast furnace route (ibid., p. 741).
- The carbon for the steel can come from coal, but also from bio-methane or other biogenic sources (ibid., p. 741).
1 Check the AI answer against your notes
For each of the passages A to D: Does your scientific source confirm what the AI answer says, does it confirm it only in part, or does it not confirm it? Name the notes on which you base your decision.
Solution
A – confirmed in part: Note 1 confirms the emissions of the blast furnace route: 1 870 kg of CO₂ per tonne of liquid steel (ibid., p. 740) is roughly 2 t. The share of the steel industry is not confirmed: note 2 gives 31 % only for industry as a whole and no figure for steel alone (ibid., p. 736).
B – confirmed: Note 4 confirms the electricity: 3.48 MWh per tonne of liquid steel for the whole process, two thirds of it for the electrolyser, while heating the ore and the electric arc furnace also need large shares (ibid., pp. 736, 739). Note 5 even makes the ‘fossil-heavy grid’ precise: with a power grid that emits more than 532 kg of CO₂ per megawatt-hour and without scrap, the process emits more than the blast furnace route (ibid., p. 740).
C – confirmed: Note 7 names the graphite electrodes in the electric arc furnace as a source of CO₂ (ibid., p. 738).
D – confirmed in part: Note 6 confirms that steel needs carbon (ibid., p. 740). ‘Often from fossil sources’ is not confirmed: according to note 8, the carbon can come from coal, but also from biogenic sources (ibid., p. 741), and your source does not say how often which one is used.
Where the AI answer agrees with your source, the evidence comes from the source: you cite Vogl et al. (2018), not the AI. Where your source does not support a claim of the AI, this is a finding in itself – you report it, but you do not use the claim (FTS-03, 1.2).
2 Test your own answer against the evidence
Go through the five sentences of your own answer one by one. For each sentence: Do your notes confirm it, confirm it only in part or only under a condition, or does the sentence name an open point that your source answers?
Solution
‘… only water is produced.’ – confirmed in part: Water is formed when the hydrogen reduces the iron ore, as Vogl et al. (2018, p. 738) show – note 3. But CO₂ still comes, for example, from lime, from the graphite electrodes and from the carbon in the steel (ibid., pp. 738, 740) – notes 6 and 7.
‘… use a lot of coal and emit a lot of carbon dioxide.’ – confirmed: The blast furnace route gets its energy mainly from coal and coke (ibid., p. 739) and emits 1 870 kg of CO₂ per tonne of liquid steel (ibid., p. 740) – note 1.
‘… remove most of these emissions.’ – confirmed only under a condition: With renewable electricity, the process has essentially zero emissions (ibid., p. 736); with a power grid that emits more than 532 kg of CO₂ per megawatt-hour and without scrap, it emits more than the blast furnace route (ibid., p. 740) – note 5.
‘… where the hydrogen comes from and how much energy its production needs.’ – an open point that your source answers: The hydrogen is made from water in the electrolyser (ibid., p. 738), and producing one tonne of liquid steel takes 3.48 MWh of electricity, two thirds of it for the electrolyser (ibid., pp. 736, 739) – notes 3 and 4. This point turns out to be decisive (FTS-03, 1.2).
‘… other materials that cause emissions.’ – an open point that your source answers: According to Vogl et al. (2018, p. 741), lime, graphite electrodes and carbon cause 53 kg of CO₂ per tonne of steel, and more CO₂ comes from mining iron ore and limestone (ibid., p. 740) – notes 6 and 7.
Your own answer took a position, gave a reason and said openly what it did not know. Now you see what you have learnt since – and this is what the reflective part of your balanced, reflective answer says (FTS-03, 1.3).
3 Choose the balanced, reflective answer
A conclusion derives directly from the results, answers only the question that was asked and acknowledges its obvious limitations (Gundogan et al. 2016, p. 70). Three students have written the footer of their poster on the hydrogen question. Which footer is balanced and reflective? What is wrong with the other two?
Footer 1
Yes. Hydrogen makes steel production climate-neutral, because the reduction with hydrogen produces only water.
Footer 2
Almost, but not entirely. With renewable electricity, steelmaking by hydrogen direct reduction has essentially zero emissions (Vogl et al. 2018, p. 736); with a power grid that emits more than 532 kg of CO₂ per megawatt-hour and without scrap, it emits more than the blast furnace route (ibid., p. 740). Even with zero-emission electricity, some CO₂ remains, for example, from making lime (ibid., p. 740). My own answer was right that the reduction with hydrogen produces water, and it said openly that it did not know where the hydrogen comes from – which turns out to be decisive. The AI answer came to a similar result but named no sources, and some of its figures were not confirmed.
Footer 3
Vogl et al. (2018, p. 736) show that producing one tonne of liquid steel by hydrogen direct reduction takes 3.48 MWh of electricity and that the process has essentially zero emissions if renewable electricity is used. According to Vogl et al. (2018, p. 740), CO₂ remains, for example, from making lime.
Solution
Footer 2 is balanced and reflective. Its first sentence answers the question as clearly as the evidence allows. The next sentences name the conditions and the limits, each with its short reference. The last two sentences reflect on how your own answer and the AI answer compare with what the source says (FTS-03, 1.3).
Footer 1 repeats your own answer and goes beyond the evidence. Your source does not say that hydrogen makes steel production climate-neutral: Vogl et al. (2018, p. 740) show that CO₂ remains even with zero-emission electricity. Such a sentence is a claim without evidence.
Footer 3 repeats the scientific answer. It is evidence, but it is not yet weighed up: it does not answer the question, and it says nothing about your own answer and the AI answer.
Bibliography
- GUNDOGAN, Buket, KOSHY, Kiron, KURAR, Langhit and WHITEHURST, Katharine, 2016. How to make an academic poster. Annals of Medicine and Surgery [online]. 11, 69–71. Available from: https://doi.org/10.1016/j.amsu.2016.09.001 [viewed 2026-10-19].
- VOGL, Valentin, ÅHMAN, Max and NILSSON, Lars J., 2018. Assessment of hydrogen direct reduction for fossil-free steelmaking. Journal of Cleaner Production [online]. 203, 736–745. Available from: https://doi.org/10.1016/j.jclepro.2018.08.279 [viewed 2026-10-19].
Overview of tools used
In creating this script, AI-supported software tools were used to generate and revise text and images according to my specifications:
| Product name | Access source | Software functions used | Scope of use |
|---|---|---|---|
| Perplexity | https://www.perplexity.ai | Search | Research |
| Gemini | https://gemini.google.com | Search | Research |
| Connected Papers | https://www.connectedpapers.com | Graphs of related papers | Research |
| Claude | https://claude.ai | Claude Opus and Claude Fable | Consistency checking, corrections, text revision and translation |
| Claude | Claude app for macOS | Claude Opus 5.5 with effort xhigh | Answer to the example question, examined in task 1 |