Plenitude ran its billboards in dark mode to prove its energy-saving claim

Plenitude, the renewables arm of Italian energy group Eni, wanted to talk about energy saving at city scale. Its first instinct, and the industry default, was a 'bright and beautiful' campaign: glossy full-colour films and brilliantly lit digital screens, because in outdoor advertising brightness equals impact and visibility equals reach. But that instinct collides with the message — burnishing a saving-energy story on thousands of power-draining LED panels undercuts the claim every escalator of the day the screens stay on.

Fighting this meant rejecting the reflex that an ad must be as bright and loud as the medium allows. Plenitude needed a way to make the outdoor advertising channel itself demonstrate the thing it was selling, so the proof would be visible in the ad's own behaviour rather than asserted by it.

LePub borrowed the dark-mode trick of consumer devices and applied it to Plenitude's own digital out-of-home screens: the ads show the campaign on dark backgrounds with dimmed creative, literally throttling how much power each screen draws while it runs. The medium (the electric billboard) is operated in energy-saving mode, so the ad acts out its own message every time it displays rather than merely claiming it.

Ran the billboards in dark mode, dimming the creative so each screen drew less power, making the ad's energy-saving claim self-evident on the very surface displaying it.

Dark mode visibly reduces screen brightness, so the saving is observable.

The proof happens on the surface the audience is looking at, making it unarguable.

The saving repeats on every exposure, reinforcing the message continuously.

Borrowing a familiar mechanic from consumer devices makes the move feel fresh and credible.

When your marketing channel contradicts your claim, make the channel enact the claim instead of asserting it.

It won a Cannes Media Lion Gold for Market Disruption plus two Bronzes; the energy-savings figures are unverified case-study self-report Whether dark mode becomes a recurring OOH idiom for sustainability advertisers is an open question, but the campaign seeded a template: an advertiser can make the channel it already pays for demonstrate an environmental claim through its own operation, which is harder to dismiss than a claim printed on the same screen.