Simple payback in 1 year
Challenge
One tall order
- When a high-rise exceeds 15 stories, controlling the building pressure is much more challenging and complex
- The Rhodes Tower experienced severe building pressure problems in winter that caused whistling elevator shafts, comfort issues and significant drafts
- The building pressure algorithms had to coexist with CO2 demand ventilation control strategies
- The stack effect pressures on elevator and smoke control shafts were uncontrolled
- Night-time/weekend set-back strategies needed to be integrated
Approach
Vertical integration
- Pathian® provided project management, engineering and commissioning services
- Installed building pressure sensors in the lobby, 41st floor and two additional sensors at intermediate elevations
- Installed VFD’s on existing constant volume return fans
- Replaced system controllers on 8 large custom AHU’s
- Reprogrammed AHU’s to Pathian control strategy
- Implemented Pathian Analytics software to track, evaluate and sustain optimal equipment performance
Results
Top to bottom improvements
- Increased comfort level across all 41 floors
- Total project cost: $150,000
- Utility Rebate (Custom/Prescriptive): $38,400
- Estimated project savings:
- Electric (806,400 kWh/yr @ $0.0969 per kWh) $78,140
- Natural Gas (6368 MCF/yr @ $4.61 per MCF) $29,674
- Simple payback: 1.03 years
- Building Energy Star certifications: 2018, 2019, 2020, 2023
Other industries
Industry
Commercial
Location
Columbus, Ohio
Building Facts
Office building
Built in 1974
1,200,000 sf
41 stories (629 ft)
4000+ employees
ENERGY STAR® certified