Integrated Energy-Saving Technology Solution for HVAC Systems
HVAC systems account for 40%-55% of total energy-saving potential. Integrated application of the following technologies can achieve significant energy efficiency improvements. First, high-efficiency cooling and heating source systems — Tier 1 energy-efficiency chillers (COP not less than 6.3, IPLV not less than 12.0) save 15%-20% compared with Tier 3 energy-efficiency units. Magnetic levitation centrifugal chillers can maintain a part-load COP of 9.0-12.0, particularly suited to the part-load operating characteristics of hotels. Second, large temperature difference and small flow systems — raising the chilled water temperature difference from 5℃ to 7-8℃ can reduce pump flow by 25%-40% and power by 35%-55%. Third, heat recovery technology — four-pipe heat recovery chillers recover condensing heat while cooling to prepare domestic hot water, improving the comprehensive energy efficiency ratio by 20%-30%, with an investment payback period of no more than 3 years. Fourth, VAV and VWV systems — when air volume drops from 100% to 50%, fan power consumption decreases by 87.5% (fan affinity laws). Fifth, natural cooling source utilization — full fresh-air operation during transition seasons uses outdoor cool air for free cooling, saving 15%-25% of air-conditioning energy consumption. Sixth, cooling water temperature optimization — each 1℃ reduction in cooling water temperature raises unit COP by approximately 2%-3%; control at outdoor wet-bulb temperature + 3℃ is recommended. Seventh, EMS automation optimization — comprehensive energy-saving rate of 8%-15%.
Lighting and Electrical System Energy-Saving Solution
Lighting energy saving — full LED replacement of traditional light sources combined with intelligent dimming control saves 50%-70% of electricity. LED luminous efficacy not less than 100 lm/W (premium 130-150 lm/W), far higher than energy-saving lamps (60-70 lm/W). GB 50034 requires LPD target values of no more than 7 W/m² for guest rooms, no more than 11 W/m² for lobbies, and no more than 18 W/m² for ballrooms. Intelligent lighting strategies: lobby automatic switching by scene (daytime, dusk, nighttime, late night); corridor occupancy sensing + scheduled dimming (10% when unoccupied); ballroom DMX512 multi-scene switching. Electrical energy saving — transformer economic operation (shutting down one unit at low load to raise the load factor to 70%-80%), power factor compensation to above 0.95, harmonic treatment (APF active power filter). Elevator energy saving — permanent magnet synchronous traction machine + variable frequency drive + energy feedback, saving 30%-45%. During non-air-conditioning seasons, elevator car lighting and ventilation are automatically shut off.
Water Supply and Drainage System Water Conservation and Hot Water Energy Saving
Water conservation measures — Grade 1 water-efficiency fixtures: toilets not more than 4.0 L, basin faucets not more than 5.0 L/min, showerheads not more than 7.5 L/min. A 400-room hotel saves approximately 18,000-22,000 m³ of water annually. Install sub-metering water meters to monitor water consumption by functional area and promptly detect hidden leaks. Hot water system energy saving — air-source heat pumps with COP 3.5-4.5 save 75% compared with electric boilers and 40%-50% compared with gas boilers. Solar hot water in areas with abundant sunshine (annual sunshine not less than 2,200 h) can meet 50%-70% of the annual hot water load. A typical solution is solar collectors + air-source heat pumps in complementary operation. Hot water pipe network insulation not less than 60 mm (elastomeric foam) reduces heat loss by 30%-40%. Variable-frequency circulation pumps with PID regulation based on return water temperature and reduced speed at night save 25%-35%. Rainwater harvesting — collect roof rainwater and air-conditioning condensate, treat and use for landscape irrigation.
Green Building Certification and Environmental Compliance Practices
MEP systems account for approximately 40%-50% of green building certification. China's GB/T 50378-2024 requires: energy saving and energy utilization (weight 30%) — cooling/heating source energy efficiency +8 points, lighting LPD compliance +6 points, renewable energy not less than 2% +6 points. Water conservation (weight 20%) — Grade 1 water efficiency +8 points, rainwater harvesting +5 points. Indoor environment (weight 25%) — CO2 monitoring linkage +5 points, PM2.5 filtration not less than 95% +6 points. LEED v4.1 BD+C scoring strategy: EA Optimize Energy Performance (18 points) — 4 points for not less than 12% reduction from the ASHRAE 90.1 baseline, 14 points for not less than 28%, 18 points for not less than 35%. EA Renewable Energy (6 points) — 3 points for not less than 5% of building energy consumption. WE Optimize Water Efficiency (12 points) — 8 points for water-saving rate not less than 40%, 12 points for not less than 50%. EQ Enhanced IAQ (2 points) — CO2 sensors + PM2.5 sensors + MERV13 filtration. Gold target: 60-79 points.