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Electronvolts to Watt-hours Converter

↔ Convert Wh to eV instead

Common Conversions

eV Wh
1 4.451e-23
10 4.451e-22
100 4.451e-21
1000 4.451e-20
1000000 4.451e-17
1000000000 4.451e-14
1000000000000 4.451e-11
1000000000000000 4.451e-8
1000000000000000000 0.00004451
1e+21 0.04451
1e+22 0.4451
2.247e+22 1

Why this conversion matters in chemistry

An electronvolt is one electron's charge moved through one volt — a vanishingly small amount of energy at any practical scale. The conversion to watt-hours falls out of two facts: 1 eV = 1.602 × 10⁻¹⁹ J, and 1 Wh = 3600 J. Dividing gives 4.4505 × 10⁻²³ Wh per eV. The conversion is mostly conceptual — it connects the atomic-scale unit of single-particle energy with the unit you read on a household electricity bill, and it underscores how many particles a kilowatt-hour worth of chemistry actually involves. A high-energy particle beam delivering TeV per particle still releases tiny energy per particle compared to a household appliance running for an hour.

Formula

Wh = eV × 4.4505 × 10⁻²³

Worked Examples

1 eV = 4.451×10⁻²³ Wh

One electronvolt — the conversion anchor, vanishingly small at the macroscopic scale.

2.247×10²² eV = 1 Wh

The number of single-eV events that add up to one watt-hour — a 22-zettaelectronvolt sum, useful as a sanity check on the prefix gap.

1000 eV = 4.451×10⁻²⁰ Wh

One keV — the photon energy range of soft X-ray and core-level spectroscopy.

13.6 eV = 6.053×10⁻²² Wh

The ionization energy of one hydrogen atom — the Rydberg energy, the foundational atomic-physics number.

Frequently Asked Questions

How do I convert eV to watt-hours?
Multiply by 4.4505 × 10⁻²³. The number is extremely small because the electronvolt is a per-particle energy and the watt-hour is a macroscopic accumulation.
When does this conversion actually come up?
Mostly conceptually — relating per-particle photon energies in eV to the bulk electrical energy needed to deliver many such particles. For practical engineering, going through joules is usually clearer.
What's the conversion derivation?
1 eV is 1.602 × 10⁻¹⁹ J, and 1 Wh is 3600 J. Dividing gives 1 eV = 4.4505 × 10⁻²³ Wh. The factor is exact through the SI definitions of the elementary charge and the second.