Stage 2 of 15 / Comparison

Choose the electrolyzer technology label

Compare PEM, alkaline and SOEC as labelled screening envelopes, not as vendor selections.

  • Advanced
  • 15 stages
  • 12 min
  • Process and energy systems
In development Green Hydrogen Plant
Draft development workbench (noindex). These stages are exercisable on a direct development route for learning and review. The journey remains a draft: not published, excluded from search/sitemap by existing protections, and not independently engineering-approved. Quantitative outputs are screening/educational where implemented and must not be treated as certified design, OEM guarantees, project approval, or bankable results.
Professional review required.Engines and workbench are implemented for draft development use. Defaults, sources, heating-value basis and engineering assumptions still require independent review. The journey must not be published or sitemap-indexed from this phase. Current verification state: Needs engineering review.

After this stage you can

Learning objectives
  • Name what the technology label does and does not change in the model.
  • State why SOEC electrical demand is not a complete plant energy statement without a heat source.
  • Record the stack kWh/kg as an assumption until a vendor curve exists.

The engineering

PEM, alkaline and solid-oxide electrolyzers differ in electrolyte, operating temperature, water quality and typical specific electricity. This journey does not simulate those physics. It records the technology as a label and checks the entered stack kWh/kg against a published screening envelope.

PEM is often chosen for dynamic renewable coupling. Alkaline remains common at large scale. SOEC can show a lower electrical kWh/kg if high-temperature heat is available; that heat is outside this model unless you fold it into the stack figure yourself.

Do not treat the envelope as a specification. Replace the specific-electricity input with a datasheet or a reviewed design point before procurement.

EngiMetric / green hydrogen educational workbench

Green Hydrogen Plant — Educational Screening Workbench

Loading the hydrogen project state...

Draft development workbench (noindex). Inputs are saved in this browser only. Calculations shown are screening/educational outputs from the existing model where implemented; missing or unsupported quantitative areas remain explicit. Completing stages records self-declared learning progress only — it is not quantitative engineering capability, not an OEM guarantee, and not industrial/project approval.

Stage

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Inputs

Saved in this browser

Edit the screening inputs for this stage, then calculate. Values you enter are marked as user-entered in the local project state; defaults remain illustrative until replaced.

Screening results

Educational model output

Results come from the existing hydrogen screening model. Unsupported quantitative areas, missing evidence, and review requirements remain explicit; outputs are not certified design or approval decisions.

Process & balance context

Textual screening views

This educational workbench presents stage-specific calculated outputs and limitations. Detailed interactive diagrams are not required for journey completion; use the stage results and assumptions panels to review boundaries, flows, energy, storage, and economics context.

Assumptions, limitations & review

From journey definition

Your deliverable for this stage

Capstone evidence

A technology choice with an explicit stack-kWh/kg assumption.

Stage assumptions, limits and sources

Provenance

Assumptions

  • Technology envelopes are illustrative bands for teaching, not performance guarantees.
  • Water quality and pressure limits are not enforced as warranty clauses.

Constraints

  • No polarisation curve, current density, temperature or degradation physics.

Limitations

  • No catalyst, membrane, KOH management or high-temperature materials model.
  • No dynamic response, ramp rate or minimum-load constraint.

Review status

  • Needs engineering review
  • Professional review is required before publication or use as a design basis.

Stage progress is stored in this browser only. The explanation and every limit on this page remain readable with JavaScript disabled; the calculators need it to run.

Stage kind: Comparison / Journey: green-hydrogen / Stage: electrolyzer-technology