How does hydrogen fit into the future energy system?

• A. Hydrogen cannot store energy.
• B. Hydrogen is primarily used as a fuel for rockets only.
• C. Hydrogen can store energy and fuel sectors hard to electrify; produced via electrolysis (green) or fossil fuels with CCS; challenges include efficiency and infrastructure.
• D. Hydrogen has no infrastructure needs.

Answer: (C)

Hydrogen acts as an energy carrier that can store energy and supply fuel to sectors that are hard to electrify. By using electrolysis, surplus renewable electricity can be converted into hydrogen and stored for later use, then converted back to electricity or used directly in fuel cells, helping to balance the grid and provide long‑term storage. There are two main production routes: green hydrogen from electrolysis powered by renewables, which emits virtually no carbon, and blue hydrogen produced from natural gas with carbon capture and storage, which lowers emissions but still relies on CCS infrastructure. Hydrogen’s versatility means it can decarbonize difficult sectors like heavy industry, long‑haul transport, shipping, aviation, and certain heat applications where direct electrification is challenging. However, this potential comes with challenges: energy is lost in conversion, the overall system efficiency is lower than using electricity directly, and it requires substantial new infrastructure for production, transport (such as pipelines and shipping), storage, and distribution, along with safety considerations and costs. Despite these hurdles, hydrogen plays a meaningful role in a diversified future energy system because of its ability to store energy and power hard‑to‑electrify sectors.