Fuel cells
Cells that turn hydrogen or other fuels straight into electricity, with heat as a by-product.
Conversion and use · Conversion devices · No. 102
- Conversion and use
A fuel cell makes electricity from hydrogen with no flame at all, and its only exhaust is water.
Chart: Illustration: Fuel cells
Where it comes from
Chart: Map of where it comes from
Hydrogen meets oxygen across a membrane or ceramic without burning, sending electrons round a circuit; a kilogram of hydrogen yields about 18.6 kWh at 56%.
Three things to know
- At room temperature a hydrogen fuel cell can never exceed about 83% efficiency, because some energy must leave as heat (calculated).
- Platinum catalyst ink and its application make up about 53% of a truck fuel cell stack's cost.
- A truck system costs about USD 282 per kW at today's low volumes, against a modelled USD 155 at mass production.
The journey
- 1 FuelHydrogen, natural gas or methanol
- 2 AnodeCatalyst splits fuel into protons, electrons
- 3 MembraneIons cross, electrons take the circuit
- 4 CathodeOxygen from air joins to make water
- 5 OutputDC power, heat, trucks or data centres