Data was analysed to determine:
- average kWh/m²/yr by occupancy category (i.e. commercial, retail)
- energy and water end-use patterns
- determinants of use patterns, such as age of building, form, function and so on
- light, thermal comfort and CO₂ levels.
This data assisted in answering the key research questions 4, 5 and 6.
A range of monitoring equipment was used to obtain data on the different aspects of supply and end uses (see the detailed monitoring results).
For each premises, this included:
- monitoring of energy data - electricity (and gas where available)
- monitoring of environmental data - temperature, humidity, lux level and CO₂ concentration
- an appliance audit
- a lighting audit
- a building audit
- a hot water systems audit
- a water audit
- an equipment audit (for example, HVAC, lifts etc.)
- an occupant questionnaire
- photographs.
Appliance audit
This involved a simple tally count by appliance type, which could be done with a single walk-through of the building with little or no disruption to the occupants. Care was taken to separate appliances by size or type where appropriate, for example, small printers (desktop), medium (floor) and large (production), and separating domestic size whiteware (refrigeration, washing machine, dryer, dishwasher) from commercial sizes. The tally was then used to randomly select which appliances to monitor.
Lighting audit
Lighting has been identified as one of the major energy end uses in non-residential buildings, and considerable effort was put into the monitoring and audit to measure and characterise lighting.
Lights were identified to a location in the building (matching the building audit floor plans) and to a switch control. Data was collected on each type of lamp in each light fitting with the wattage and total number recorded. The lamp type and control type were recorded. The wattage was either read off the lamp (if readable) or estimated from a table of typical values. This audit data enabled room-by-room or area-by-area calculations of lighting stock and lighting power density to be made.
Building audit
The purpose of the building audit was to collect information on the physical characteristics of the building, enabling the creation of computer simulation models.
Hot water systems audit
Where hot water systems were accessible, information on them was recorded. The systems were often in out-of-the-way places in non-residential buildings, and access could be difficult or impossible. At a minimum, the temperature of hot water was obtained.
Water audit
The water audit collected basic information about water use in the building, including the number of water outlets in use (for example, taps and dishwashers). The water meter was located (if it existed) and monitoring equipment fitted where possible.
Equipment audit
The equipment audit covered large equipment used for central services (such as HVAC systems and components, servers, lifts, boilers etc.).
Occupant questionnaire
The occupant questionnaire mainly covered occupancy and schedules and was usually done at the time of the installation. The comprehensive, internationally validated BUS survey was also used (see www.usablebuildings.co.uk).
Photographs
Using photographs, particularly for the exterior elevations, greatly reduced the amount of time required on site. Digital photographs were taken of:
- all exterior elevations
- surrounding buildings and terrain
- the interior
- distribution boards where equipment was installed
- logger locations
- all major equipment (e.g. hot water systems, HVAC, chillers).
Some were a record of the installation to assist in recall and identifying any problems later, and some were to record information that would be extracted and coded later (for example, to identify glazing area or site shading on exterior elevations).