Key card systems that switch off electricity in rooms

Principle

Some key card systems are designed to switch off the electricity supply when rooms are not occupied, avoiding excess power consumption (television set, lights, etc.).
When the customer inserts the card key in the energy-efficiency device the electricity is switched on; when the customer leaves the room and removes the card the electricity is cut off.

Explanations

When is the best time to install key card locks?
• As the key card device must be wired to the room's electricity circuit, it is best to install this type of system when electrical work is done in guest rooms.

Implementation

Room electrical circuits must be connected to the key card device by a professional electrician.
Remarks:
• Power supply can be maintained to some devices (minibar for example) when the room is not occupied. In this case the key card installation must be appropriately wired.
• Automatic control of power supply to guest rooms depending on occupancy can also be integrated into a building energy management system, if any. In this case electricity controls are generally linked to the room heating/cooling system. When keys are returned to the reception desk both heating and power are shut off in the room.

Costs

Approximate cost:
• variable. It is difficult to give a final price for this type of installation, as it depends on labour costs, and whether the hotel must be closed during the work period, etc.
Approximate payback time:
• can be under 3 years (the larger the hotel, the shorter the payback time)
It should be noted that costs and payback times are highly dependent on the local setting and the initial situation of the hotel.

Examples

The Hotel Morgane (Chamonix) installed energy-saver key cards for guest rooms: the power supply is automatically cut of when customers remove the energy-saver card. For instance, lights are automatically switched off when customers leave the room. This system is linked to the building energy management system that was install prior to the renovation work. This computerised system collects and process all energy data for the hotel. By optimising regulation and control of existing equipment, significant energy savings are achieved (between 20 and 40% savings compared to a building without an energy management system). Each room is equipped with automatic controls to turn off heating when windows and French windows are opened.
The Ferme de Bassilour, a hotel in Bidart (Pyrénées Atlantiques) equipped guest rooms with automatic power controls that shut off the electricity supply when customers leave the room (excepting the minibar that needs a continuous power supply).

Benefits

Cost savings
Energy savings:
• Hotels equipped with room key card systems and power controls state that electricity used in rooms is reduced by as much as 30%.

Comfort improvement
Greater convenience for employees:
• Automatic power controls in rooms simplify work for employees, who do not have to check electrical devices (television set, lamps, etc.) that might have been left on.

Reduced carbon and

CO2 emissions•
• For a hotel of 1,000 m² that uses 77.5 kWh/m² of electricity in guest rooms annually, and applying emission factors for France, a 35% savings in energy consumption represents:
1.63 t CO2 eq of avoided emissions each year
Emission factors for electricity in France: 84.3 g CO2 / kWh.
Emission factors for natural gas in France: 331 g CO2 / kWh (Source: ADEME).

Constraints

Implementation:
• Ease of implementation: Moderate (**).
• Best time for implementation: when electrical work is done in guest rooms.
• Relevant initial situation: the hotel is not equipped with a room key card system.