A single email has an almost negligible impact. But it is the accumulation of billions of unnecessarily stored emails that raises questions.
Sending an email costs almost nothing. The result: it has become a reflex. But it is the accumulation that raises questions.
360 billion emails are sent each day. Conservatively assuming that only 10% are never deleted, that represents 36 billion emails per day accumulating on servers.
In data volume:
105 GWh/year
just for the storage of useless emails
Servers run 24/7, even when an email is never consulted. Storing data has a constant energy cost.
3 million TB (with replication ×3) × 35 kWh = 105 GWh per year, just for the storage of useless emails.
hours of TV (100W television)
smartphone charges
to 12,000 datacenter servers running permanently
of CO₂ according to the European energy mix 295g CO₂/kWh — IEA 2023
of CO₂ according to the American energy mix 386g CO₂/kWh — EPA 2023
500W solar panels installed in Normandy 500 kWh/an/panneau — PVGIS
Note: these figures are estimates based on conservative assumptions. They only cover the storage of useless emails from a single year — and accumulate year after year. The total impact of digital technology is much broader.
Every server, every hard drive requires materials whose extraction is energy-intensive and polluting.
Steel, aluminium, copper, silicon
Server components and casings
Lithium, cobalt, tantalum, rare earths
Gold, silver, palladium
The extraction of these materials causes deforestation, soil and water pollution, and often inhumane working conditions.