Peak demand reduction pilot shows encouraging results for mall

Promising energy management at the height of Texas summer

The Woodlands Mall is a bi-level, enclosed shopping center located 30 miles north of Houston. The mall was renovated in 2004 and since then Woodlands has been included in portfolio-wide energy management upgrade plans. As the Houston area utility had recently instituted peak demand pricing, Woodlands Mall was a prime candidate for a demand reduction pilot.

Spearheaded by Buildings IOT, the corporate master systems integrator of record for BPR, a peak demand reduction test system was developed. By reducing energy usage in common areas during the utility company’s pre-determined peak hours, Woodlands could experience significant overall energy cost reductions.

Working under the management and integration direction of Buildings IOT, we created a custom solution for automatic demand control for the mall's HVAC system based on electrical consumption. The demand management program uses SkySpark for system monitoring and notification, Niagara for building automation control and BACnet and Modbus for communication protocols across controllers.

Challenges

• Because analytics had not been previously utilized on Woodlands' HVAC system, the actual status of electricity meters was not known at the outset of the project and therefore actual peak reductions could have been far less than projected.
• Initial analysis of utility billing data was required to understand the demand charges for common areas before the demand management strategy could be finalized.
• Project development spanned seasons and was delivered at the peak of summer heat when equipment was operating in high gear and guest comfort was a top priority.

Successes

• Peak reduction of approximately 100kW achieved just three days after implementation, at the end of July when outside air temperatures were in the high 90s.
• Since initial implementation, the project continues to return monthly energy reduction of 5,000kWh.
• Additional development of peak demand prediction and pre-cooling algorithms has provided 30% additional cost savings on this project than at first delivery of the project in July.
• Based on this pilot project, Brookfield Properties Retail has expanded demand management to additional properties in its portfolio.