One of Dubai’s largest shopping centres has dramatically reduced the energy consumption of its enormous chilled water plant through the implementation of PlantPRO®.
The shopping centre features a gross leasable area of 196,000m² with 465 retail stores, restaurants and cafes, large open atrium, a 10–screen cinema complex, and a leisure and entertainment precinct.
Air conditioning is provided to the centre by an enormous chilled water plant that dwarfs even the largest chilled water plant found in Australian buildings.
At the heart of the centre, a chiller plant containing six 8900kWr (2530 ton) York chillers operates 24 hours a day, 7 days a week to provide chilled water for the centre’s air conditioning. These chillers are accompanied by six very large cooling towers, and a total of 39 pumps – some as large as 250kW each.
Around 15 chiller plant operational staff are employed to maintain and monitor the chilled water system around the clock.
PlantPRO controls all the equipment in the centre’s central plantroom including the chillers, primary and secondary chilled water pumps, condenser water pumps, cooling towers and a large number of motorised valves.
Chiller staging and sequencing by PlantPRO is based on a fully user-configurable, intelligent dynamic load based strategy.
PlantPRO communicates with the site BMS (building management system) via the seamless integration of the BACnet protocol, and uses existing BMS infrastructure as a gateway to control and optimise the chiller plant operation. This provides a very efficient and cost effective solution, and saves thousands of dollars that would otherwise be spent on new sensor installation, DDC controllers, programming and wiring.
Significant energy savings
Data from the centre’s Facility Manager was provided to allow for a statistical model and energy baseline to be produced independently. A baseline period of 1st July 2016 to 30th June 2017 was utilised.
When comparing against the baseline, energy savings of 4.9% have been achieved at the centre under PlantPRO control between 1 July 2017 and 27 January 2018. This equates to around 840,000kWh of electrical energy being saved over the period.
In dollar terms, this represents approximately $USD100,000 in electricity savings.
It is important to note that almost 15% (14.84%) in energy savings was achieved in January 2018 alone – saving 200,000kWh and approximately $USD23,000 in electricity costs.
PlantPRO was able to deliver significant energy savings by intelligently staging and sequencing the chillers on site, providing smart pump control, optimizing condenser water equipment control and providing dynamic chilled water set point management.
Additionally, PlantPRO’s extensive, built-in monitoring and verification engine allowed for a number of existing plant anomalies to be identified, including existing issues with chilled water network flow and secondary network water flow and pressure.
The effect of PlantPRO on the chilled water plant serving the centre continues to be monitored by Conserve It. As the seasons change, it is expected that further gains in energy efficiency will be achieved.