Smart lighting and energy transition: comprehensive guide to optimize your building's performance

Faced with the growing challenges of energy transition and evolving regulations, smart lighting is emerging as a strategic lever for businesses and communities. But concretely, what does this modernization represent? What are the key figures to know, the obligations to respect, and the available subsidies?

About the author

Léo PEREZ

Energy Efficiency Manager & Head of C.G.S. BU (CLAREO GLOBAL SOLUTION)
at Clareo Lighting

Lighting: an often underestimated consumption item

Lighting represents a significant portion of building energy consumption, varying greatly by sector:

• Offices: approximately 20% of total consumption
• Logistics / warehouses: up to 40%
• Parking lots: up to 80% of energy consumption
• Industry: less than 10% (machines being the main consumers)
• Residential: relatively small portion compared to heating and appliances

These figures show how strategic this item is in an approach to reducing consumption.

A still largely obsolete stock

Today, nearly 60% of France's lighting stock has not yet migrated to LED technology. However, the transition is accelerating, particularly due to:

• The gradual end of fluorescent tube production
• The application of the Commercial and BACS decrees
• The climate emergency and the goal to reduce energy consumption by 40% by 2030

LED is therefore no longer just an option, but a technical, regulatory, and economic necessity.

The BACS and Commercial decrees: obligations and deadlines

The BACS decree: what is it?

This refers to decree no. 2020-887 of July 20, 2020, supplemented by decree no. 2023-259 of April 7, 2023, relating to automation and control systems for commercial buildings. This decree requires the implementation of a BMS (Building Management System), a computerized system for remotely controlling multiple building systems via controllers and sensors.

Priority objective: monitor, record, and analyze energy consumption data to regulate technical systems' consumption according to real-time needs, with a target reduction of up to 25% of energy consumption.

Who is concerned and when?

Existing buildings:

• Sites equipped with an air conditioning or heating system (combined or not with a ventilation system) whose rated power exceeds 290 kW on January 1, 2025 or 70 kW on January 1, 2027

New buildings:

• Since 2021: buildings over 290 kW
• Since April 4, 2024: buildings over 70 kW

The Commercial decree: ambitious goals

Commercial buildings over 1,000 m² must reduce their energy consumption:

• -40% by 2030
• -50% in 2040
• -60% in 2050

Compared to a reference year chosen between 2010 and 2019.

Specific lighting requirements

According to the BACS decree, it is necessary to implement:

1. Remote ON/OFF control (minimum requirement)
2. Presence sensors to turn on only when necessary
3. Light sensors to adjust lighting according to natural light input
4. Information feedback to the BMS
5. Consistency with HVAC: heating/air conditioning and presence synchronization

These devices are essential to achieve level A in BMS and be eligible for energy savings certificates (EEC).

The three levers to maximize savings

1. Migration to LED

Simply switching from traditional lighting to LED allows an average reduction of 50% in energy consumption for this item.

2. Intelligent management

By integrating presence and light sensors, additional savings are significant:

• Offices: up to 40% additional savings
• Logistics: approximately 60%
• Parking lots: up to 80%

3. Installation study and sizing

Adapting the power and placement of luminaires through a photometric study not only optimizes savings, but also improves occupants' visual comfort. The Dialux tool allows space modeling taking into account numerous parameters: materials, ceiling height, furniture type, areas to be lit, maintenance factor…

The balance between energy savings and work costs is fundamental: the healthiest solution is to provide adapted lighting, with the lowest possible power, while respecting the regulations specific to each zone.

Management technologies and solutions

Wired vs wireless systems

Wired DALI:

• Fine management through sensors (detection, dimming, time scheduling)
• Reliable but more complex to integrate in renovation
• Less scalable in the long term

Smart Lighting (wireless):

• Rapidly growing system based on technologies like Bluetooth
• Intelligence integrated directly into luminaires
• Great flexibility and reduced installation cost in renovation
• More expensive equipment but significant gains

BMS communication protocols

To facilitate exchanges between equipment, several protocols are used:

• BACnet
• KNX
• DALI
• LonWorks
• Modbus
• API

Regardless of the technological choice, the essential thing is to aim for coherent and integrated building management.

EEC and BMS: maximizing financial assistance

The strategic duo BMS & Lighting

BMS plays a key role in EEC valorization. Systems are classified according to their functionalities: the higher the class, the greater the subsidies awarded.

Requirements for EEC eligibility

• Natural light consideration
• Presence detection
• Remote control via BMS
• Centralized information feedback
• Consistency with HVAC management

Available subsidies

EEC (Energy Savings Certificates):

• Main subsidy often covering a significant portion of equipment costs
• Value multiplied up to 2.5 times with EPC (Energy Performance Contracts)

Pay-per-use financing:

• Work costs spread as rent
• Equivalent to generated savings
• Operating budget rather than investment

Green Fund (public establishments):

• Combinable with EEC

EPC (Energy Performance Contracts):

• Guarantee achieved savings

Return on investment

ROI depends on the scope and can be estimated as follows for LED renovation with detection:

• Offices: approximately 4 years
• Logistics/Industry: between 2 and 3 years
• Parking lots: between 1 and 2 years

This ROI can be further reduced through subsidies (EEC, EPC) and precise optimization of the installation.

Common mistakes to avoid

In design and installation

• Lack of anticipation regarding BMS in the upstream phase
• Poor sizing leading to under or over-lighting
• Unsuitable equipment (reflections on screens, for example)
• Programming poorly adjusted to actual usage

In renovation

• Confusion between renovation and simple "relamping"
• Ignoring upcoming regulatory changes
• Failing to understand that lighting affects comfort, energy performance, and building technical management

"Even high-performance technology loses all its value if poorly implemented."

Smart Lighting trends and benefits

Emerging trends

"Smart lighting" projects are increasingly common, especially in renovation, thanks to:

• Ease of implementation
• Intelligent integration into BMS/BCS
• Feedback of numerous data useful for overall energy optimization

Multiple benefits

Beyond energy savings (generally 30 to 60% additional depending on site usage), intelligent management provides:

• Increased comfort for users through lighting adapted to their needs
• Building valorization and certification (BREEAM, etc.)
• Facilitated maintenance through reported data
• Management cost optimization
• Multifunctional data collection: luminaires become sensors capable of transmitting information to the BMS

Conclusion: Lighting better to consume less

Reducing energy consumption related to lighting involves three major combined levers: switching to LED, intelligent management, and installation optimization. These actions generate significant savings while meeting regulatory requirements.

The barriers to transition remain the difficulty in making people understand the value of a higher initial investment for lasting gain, as well as the slowness of decision-making. Yet, each day of delay equates to money lost and CO₂ unnecessarily released.

"Lighting is good. Lighting at the right time, in the right place, and in the right way is even better. Making a gesture for the planet is good. Making the right gesture is even better."