Every Friday for four weeks, listeners of bel RTL’s Positive Attitude programme heard Sandrine Corman take on a new challenge – an energy challenge. She was trying to improve her household energy score, live, with an ENGIE expert by her side, and her audience was following along.
The app and the audience
The ENGIE Smart App centres on a key utility feature: an A to E energy score that shows users exactly where their household consumption stands and what that means financially. The feature is relevant to anyone paying an energy bill, but getting a broad audience of 30- to 50-year-olds to actively engage with it is harder than the product merits. That age group manages real household budgets and energy costs, but tends to tune out corporate digital messaging quickly. ENGIE needed a format that felt like a service rather than an advertisement, and a face that the target audience already trusted.
The show-don’t-tell approach
Sandrine Corman is not only a bel RTL host, but also a well-known personality in French-speaking Belgium with 90,000 Instagram followers, predominantly local, and the 30 to 50-year-old age bracket. Instead of talking about the app, she was asked to use it by the ENGIE expert in her radio show, and share what happened.
Over four weeks, she posted at-home Instagram stories documenting each weekly challenge: the shower challenge, fridge optimisation, and more. Her energy score improved visibly as the campaign progressed. Followers could see the results before committing to a download. Questions and tips started appearing in the comments organically. The app’s core feature was being demonstrated in a domestic setting that the target audience recognised as their own.
How the media ecosystem worked
Three channels played three different roles:
- Radio (bel RTL): The Friday Positive Attitude segment anchored the weekly rhythm, pairing Sandrine and Hugues Hamelynck with an ENGIE expert. It established authority, delivered mass reach, and set up the weekend content.
- Instagram (Sandrine Corman and bel RTL): Sandrine’s personal stories carried the emotional and practical proof. The bel RTL account extended the storytelling and added weight.
- Digital hub (be): A dedicated landing page consolidated tips and app install links, turning engagement into measurable action.
Figures and key details
- Radio reach: 350,000+
- Social media reach: 250,000+
- Total combined reach: 600,000+
- Social interactions: nearly 2,000 likes, comments and saves
- Key demographic: 30 to 50, French-speaking Belgium
- Campaign duration: four weeks
Right audience, right format
Rather than explaining, this campaign demonstrated. The difference in audience response was seen in the numbers and in the comment sections, where followers were asking questions about their own energy scores and sharing tips unprompted.
The role Sandrine Corman played was effective not because of her follower count but because her audience profile matched ENGIE’s target precisely. Radio gave the campaign a weekly moment of authority, while social gave it continuity and proof. The challenge format gave the audience a reason to stay involved rather than scroll past. A product became a story worth following because the campaign was built around the right person, the right format, and a rhythm that respected how that audience spends its time.