The Molleaumètre is a self-powered shower flow meter, designed in France by Molleau, that measures water use in real time and cuts it by an average of 23% per shower, and up to 61%, through colour-coded visual feedback. A connected version with a central dashboard is available for managers of residences, hotels and social housing.
The Molleaumètre is a smart device that fits onto the shower hose in a few minutes. It measures the volume of water used in real time and displays it.
While the screen shows the volume, the light ring moves from green to amber and then to red as each threshold is crossed. Users see where they stand at a glance, an engaging, behaviour-led approach that raises awareness without imposing anything.
The Molleaumètre powers itself through a hydroelectric micro-turbine. It sends shower data to a dashboard, giving residence managers and hotels a complete view of water use across their showers.
The Molleaumètre combines a real-time display of the volume used with a colour code by threshold. Together, the two let every user make a conscious, informed decision, with nothing imposed.
Inform rather than constrain. The Molleaumètre draws on behavioural science and on boost theory (Hertwig & Grüne-Yanoff, 2017): rather than steering a choice without the person realising, it gives them the means to decide, through clear, immediate and intelligible information that lastingly strengthens their ability to act.
1. Immediate feedback. Residents see their consumption in real time. Not afterwards, not on a bill three months later, but at the precise moment they can act on it.
2. An intuitive benchmark. The colour code (green, amber, red) instantly turns litres into a clear reference point: one glance is enough to see where your shower stands. This is the principle of natural frequencies, presenting information in a form the mind grasps immediately, so the decision follows naturally.
3. Autonomy preserved. No reduced flow, no timer, no cut-off. Residents stay fully in control, and it is precisely because the change is chosen that it lasts.
The Molleaumètre screws onto the shower hose in a few minutes. It starts as soon as the shower does.
By hand, no tools needed.
Standard ½" thread. Compatible with all hoses.
Onto the Molleaumètre. It stays discreet, in line with the hose.
Turn on the water: the ring lights up and measurement begins.
Beyond the device itself, Molleau provides a management platform: water saved, money saved, CO₂ avoided and the spread of showers across thresholds. Filter by period, residence or usage category. Built for your technical, sustainability and communications teams.
We equipped an entire student residence near Place d'Italie in the 13th arrondissement of Paris, fitting a Molleaumètre in every shower. For the first few weeks the device displayed nothing, in order to establish a baseline. The display was then switched on, showing the litres used and signalling heavier showers through colour. The effect was immediate: students cut their consumption by 23% per shower, and by up to 61% among the heaviest users, and the change lasted.
Discuss a pilot with us“You barely notice it. It is just there, and it changes the way you shower without you even thinking about it.”
RESIDENT, PLACE D'ITALIE · ONE-MONTH SURVEY
Demanding conditions, shared bathrooms, hard water, heavy use. The Molleaumètre is designed to last.
Works at low flow rates. A turbine flow meter measures cumulative volume to the litre, from the start of the shower to the end.
Self-powered by the water flowing through it. No battery, no cable, no maintenance.
Shower data is sent to a central dashboard. Nothing to install on the resident's side.
Compatible with all standard hoses on the market. No noticeable pressure loss for the user.
Designed to withstand shower conditions. Parts in contact with water are selected for drinking-water compatibility.
Designed for around 30,000 cycles.
Full technical datasheet available on request, get in touch.
The questions we are asked most about the device, installation and rollout. Something else on your mind? Write to us.
On average 23% per shower, measured in the Hénéo pilot. The heaviest users reach up to 61%.
Results measured in the Hénéo pilot (RIVP group): 23% less per shower and 15.5% less on the building's main meter, across 3,140 showers. The effect holds over time.
No. The Molleaumètre screws onto the shower hose in a few minutes, without tools. No work inside wet rooms, no water shut-off and no alteration to the property.
The connected B2B version comes with a web dashboard and an iOS and Android app for property managers.
The unconnected consumer version works entirely on its own: the light ring is all you need, with no app required. A consumer app is planned for 2026 for those who want to track their showers.
No. Unlike aerators or flow restrictors, the Molleaumètre does not restrict the flow. Pressure and perceived flow remain exactly the same.
There is no battery. The Molleaumètre is self-powered by a built-in hydroelectric micro-turbine: the water flowing through it generates the electricity the device needs. No maintenance and no electronic waste.
Each Molleaumètre sends its data over Bluetooth to a gateway installed in the building (included in the Pro rollout). The gateway relays the data to our dashboard in real time.
Residents do not have to do anything and no app is required. The data is anonymised per shower.
Any organisation with a significant number of showers:
• Social housing landlords (pilots under way with Hénéo / RIVP and In'li)
• Student residences
• Hotels, holiday clubs and hostels
• Young workers' hostels, senior living and care homes
A shower meter with visual feedback such as the Molleaumètre cuts water use by 23% per shower, and by up to 61% among the heaviest users. In the Hénéo pilot (RIVP group), consumption also fell by 15.5% on the building's main meter once the light ring was activated, with no loss of comfort.
The most effective and least intrusive method is to make consumption visible in real time rather than restrict the flow. The Molleaumètre fits onto each shower hose in a few minutes and displays a colour code (green, amber, red) that naturally guides behaviour. On the management side, a dashboard brings together consumption across the whole portfolio, property by property, so savings can be managed and evidenced.
Yes. The Molleaumètre is self-powered by a hydroelectric micro-turbine: the water passing through it generates the electricity it needs. No battery to replace, no charging, no electronic waste and therefore no maintenance for the operator.
With an average saving of around a quarter of hot water use, the Molleaumètre generally pays for itself in under two years across a significant number of showers, because hot water combines the cost of the water itself with the cost of heating it. The dashboard continuously tracks the litres and the money saved, property by property, so you can follow the real return on investment.
Yes. By reducing hot water consumption it acts directly on two areas covered by the French Éco Énergie Tertiaire scheme, known as the décret tertiaire: water and heating energy. Consumption data can be exported to feed your CSR reporting, non-financial performance statements, French Climate Law obligations and CRREM. A sample report is available in the Resources section.
Yes. Each Molleaumètre screws onto the shower hose in a few minutes, room by room, with no water shut-off and no plumbing work. Rolling out across dozens or hundreds of rooms happens gradually, without closing spaces or disturbing guests and residents.
An A4 preview of the annual reporting we provide to your sustainability and asset teams, with indicators for non-financial reporting, the French Climate Law and CSRD.
View →A full summary of the Place d'Italie rollout: protocol, measurements, resident feedback and lessons learned. Sent on request.
Request it →The France 2 Télématin feature, Matrice presentations and pilot feedback in pictures.
Visit the press area →Thirty minutes to estimate the savings potential across your portfolio and see whether Molleau fits your situation.