Hydrogen Energy Storage Lab
Classroom worksheet · Interactive simulation: https://lkforge.com/tools/physics/hydrogen/
Name: Date:
Learning objectives
- Describe storing energy as hydrogen.
- Explain electrolysis and fuel cells.
- Discuss round-trip efficiency.
Variables to change
- Electrolysis power
- Stored hydrogen
- Fuel-cell load
Procedure
- Use electricity to split water into hydrogen and oxygen (electrolysis) and store the hydrogen.
- Run the hydrogen through a fuel cell to regenerate electricity.
- Compare the electricity in with the electricity recovered.
Observations
Record energy in during electrolysis vs energy out from the fuel cell.
Questions
- How is energy stored as hydrogen?
- How is the energy recovered?
- What is the round-trip efficiency like?
- What is the byproduct of a hydrogen fuel cell?
- Why use hydrogen despite lower efficiency?
Answer key (instructors)
- 1. Electricity splits water into hydrogen and oxygen (electrolysis); the hydrogen holds chemical energy.
- 2. A fuel cell recombines hydrogen with oxygen to produce electricity (and water).
- 3. Relatively low — often ~30–40% — because both electrolysis and the fuel cell lose energy.
- 4. Water (plus heat).
- 5. It stores large amounts of energy for long durations and can decarbonize hard-to-electrify uses.
Hydrogen storage uses surplus electricity to electrolyze water, stores the hydrogen, then runs it through a fuel cell to regenerate electricity, emitting only water. Round-trip efficiency is modest (~30–40%) but it enables long-duration, large-scale storage.