Fuel Cells and Hydrogen Energy

Definition

A fuel cell is a device that converts the chemical energy of a fuel, usually hydrogen, directly into electricity through a reaction with oxygen, producing water as the main by-product.

Key points

• In a hydrogen fuel cell, hydrogen and oxygen combine; the only emission is water, which makes it a clean energy source at the point of use.
• Unlike a battery, a fuel cell keeps producing electricity as long as fuel is supplied, rather than storing a fixed charge.
• Hydrogen is classified by how it is made: "green" hydrogen from water using renewable electricity (electrolysis), "grey" from natural gas with carbon emissions, and "blue" from natural gas with carbon capture.
• Uses include hydrogen fuel-cell vehicles, backup power, and spacecraft; hydrogen is also used directly as a fuel.
• India launched the National Green Hydrogen Mission (approved 2023) to make the country a hub for green hydrogen production and to cut fossil-fuel dependence (verify the latest targets).

Why it matters for CAPF

Fuel cells, hydrogen as a clean fuel, the green, grey, and blue hydrogen distinction, and India's National Green Hydrogen Mission are recurring energy, environment, and current-affairs items linked to energy security.

Common confusion

A fuel cell is not a battery; it generates electricity from a continuous fuel supply rather than storing charge. Hydrogen is clean only at the point of use; whether it is truly green depends on how the hydrogen was produced (green versus grey).

Related concepts

concept biofuels, concept catalysts, concept greenhouse effect

Parent note

chemistry everyday