Driven by the "dual carbon" goals, building energy consumption monitoring has become a key component of green transformation for commercial complexes. This article shares the complete implementation experience of an energy monitoring system in a large commercial complex (120,000 square meters) in a second-tier city.

1. Project Background and Challenges

The project includes three business types: shopping mall, office building, and hotel, with annual electricity consumption exceeding 20 million kWh. The core challenges faced by the owner include:

• Dispersed energy data without a unified collection and analysis platform
• HVAC systems account for 45% of total energy consumption, but operation strategies are rough
• Lack of intelligent lighting control, resulting in lights-left-on phenomena
• Inability to accurately evaluate energy-saving renovation effects

2. Solution Design and Sensor Deployment

Based on site surveys, we designed a hierarchical monitoring architecture:

1. Power Monitoring Layer

Deploy three-phase multi-function electricity meters in the main distribution room and floor distribution rooms to monitor voltage, current, power factor, and active power. Key circuits include: central air conditioning chillers, cooling water pumps, cooling towers, lighting buses, elevators, etc.

2. Environmental Parameter Layer

Deploy temperature, humidity, and CO₂ sensors in typical areas (lobby, retail spaces, office areas, machine rooms) at a density of approximately 1 set per 200 square meters. An outdoor weather station collects temperature, humidity, and illuminance data.

3. Cooling Capacity Monitoring Layer

Install ultrasonic flow meters and temperature sensors on the chilled water supply and return mains to calculate cooling capacity consumption in real-time.

3. Data Collection and Platform Construction

The system adopts an "edge gateway + cloud platform" architecture:

• Edge side: Modbus RTU/TCP collects electricity meter data, LoRaWAN wirelessly transmits environmental parameters
• Platform side: Real-time database storage based on MQTT protocol, providing visualized Dashboard and alarm functions
• Sampling frequency: power data 1 minute, environmental data 5 minutes

4. Operational Results and Energy Saving Analysis

After 6 months of operation, significant results were achieved:

• Overall energy consumption decreased by 18%, saving approximately 1.8 million yuan annually
• HVAC system energy consumption reduced by 25% through load prediction-based intelligent control
• Lighting system achieved 35% electricity savings through occupancy sensing + daylight harvesting
• Fault response time shortened from average 4 hours to 30 minutes

5. Experience Summary

1. Sensor selection should suit local conditions: Higher precision is not always better; balance cost and requirements

2. Data quality is the core: Spending time on point planning and calibration ensures accurate analysis

3. Energy saving is a systematic project: Monitoring is only a means; it must combine with operation processes to create value

4. Continuous optimization is important: Review data quarterly and adjust control strategies

Energy consumption monitoring is not simply "installing meters for measurement" but using data to drive building operation upgrades. For commercial complexes planning or renovating, we recommend starting with core systems (HVAC, lighting) and implementing in phases.