Data is the key to optimising energy performance

Originally posted in the Energy Efficiency Council's May 2020 newsletter.

The COVID-19 pandemic has forced building owners and operators to take unprecedented steps in managing shopping centres.

The lockdown has dramatically increased the pressure on operations teams to cut costs and prioritise health and safety. Economic conditions have increased the pressure on building owners to cut outgoings, including their energy costs. However, shutting down the energy-using systems in empty buildings is extremely complicated, and many offices and shopping centres have faced the even more challenging situation of being partially occupied.

Our engineers have been flat out helping commercial business customers adapt their building operations to these new conditions. The data from these sites have told us a very intriguing story about the impact of COVID-19 on energy consumption, particularly among shopping centres.

CIM Retail Energy Index

We’ve aggregated the data from the Australian shopping centres we work with to publish the CIM Retail Energy Index. This index demonstrates that occupancy across our retail customer sites fell below 40% in late March following government-mandated closures of gyms and cinemas, and decisions by other retailers to close due to health and safety concerns.

As a result of these closures and the work being carried out in shopping centres to optimise the systems in these centres for partial occupancy or complete shutdown, there has also been significant falls in energy consumption.

Energy use is down 35 per cent compared to the same time period last year.

This result is consistent across all the centres we are working with as the types of stores closing or staying open is the same in every centre, which determines what equipment needs to keep running and what can be shut down completely.

Heating, ventilation and air conditioning (HVAC) consumes up to 65 per cent of a large building’s energy bill, which is why streamlining operations to match demand is a critical element of building management strategies for retail customers, enabling them to cut costs without sacrificing health and safety.

Scaling back operations or putting the system into full hibernation, however, is not as straightforward as flipping the switch and walking away. It requires careful planning and management.

Building systems are complex and interconnected

Building systems are complex and interconnected, often comprising hundreds of expensive components and pieces of equipment. Incorrectly adjusting these systems can adversely affect equipment operation and cause costly breakages or indoor air quality health and safety risks. For example, HVAC systems need to be powered down and up in very specific ways to minimise the risk of Legionnaires disease.

In many shopping centres this task is made even more complicated by the interaction of old systems with newer systems that have been added as the centre expanded. Building analytics help building owners and operators identify safe and effective ways to power down their operations.

Optimising shopping centres

Based on this analysis, the shopping centres we work with have implemented a range of measures to limit energy consumption and cut costs, including:

• Reviewing operating schedules to reflect occupancy;
• Locking-out zones, tenancies and floors that are unoccupied;
• Limiting chiller or boiler operation through lock-outs, staging or widening setpoints;
• Widening internal temperature setpoint dead bands;
• Optimising car park exhaust fan schedules;
• Correcting operating schedules for specific retail tenancies; and
• Preserving operation and conditions of critical areas such as data or server rooms.

As retailer confidence in reopening grows, we are now seeing a recovery of occupancy above 50 per cent, with expectations for it to rise back above 70 per cent as lockdown is eased even further. This means that many building owners will need to prepare to restore normal operations, a process that also needs to be carefully managed.

However, as the lockdown lifts, we believe that building owners and operators will need to go beyond just bringing their buildings back online, and take further steps to optimise their assets. The heath impacts of buildings will be closely scrutinised over the coming year, and budgets will continue to be squeezed tightly; now is a good time to make sure existing systems and equipment are operating as efficiently as possible.

As the real estate sector focuses on how it can do more with less, and make smarter capital planning decisions to optimise budgets, using data to better understand buildings will be the key to making the most of existing assets.