Development of protocol for sub-metering for ventilation models and verification for shopping centres

Shopping centres are complex buildings with specific needs. The use that different areas are put to affects energy consumption, whereas the different functional patterns and stakeholder groups influence energy use. They are also associated with specific requirements that make it relevant to consider different types of performance indicators.
The study investigates the energy conservation measures applicable for management, operation and use of shopping centres and aims to perform the measurements and verification of the energy savings of shopping centres. Its main focus was to track inefficient use and user implications in complex buildings (shopping centres) with focus on the ventilation. First, the main predictor variables and performance indicators associated with ventilation were identified.
A protocol for sub-metering of ventilation related energy consumption and flows (mainly electricity for fans, but also heating and cooling) was defined as necessary basis in order to be able to track inefficient use and user implications. User profiles were split into sub-categories, owners, tenants (shop owners, differentiating by size and type) and end-users (shopper, with appropriate differentiation) are three minimal differentiations.
Energy can be considered to follow function because energy in the end is used to meet requirements defined by the activities that take place in a shopping centre. In a SC, requirements are diversified by the type of tenants (shops, retail, restaurants, cafes, etc.), by the size of tenants rental space (stalls, retail units, independent anchor stores etc.), or by the type of spaces (common areas, offices, storage etc.). The different activities can be characterized by functional patterns for various groups; – opening hours for customers will differ from operational hours for technical services and lighting. Facility operation has to meet the requirements of staff before the shopping centre opens to the public. In shopping centres, many tasks are performed outside of opening hours which require maintaining health and safety for the workers. Examples are cleaning, sanitation, loading and re-stocking of goods. In relation to this, the ratio of full operation of HVAC and lighting vs. opening hours or service hours is one index that could be used as a performance indicator.
The proposed method provides a solid basis for validation and thus performance based economic models that were introduced in order to be able to quantify cost-effective refurbishment investments of ventilation systems and strategies. The results of key performance indicators provided valuable input in the decision making process for deep retrofitting plans. Different proposals for visualization of results (feedback to managers, tenants, customers) were investigated and are discussed.