02. Energy monitoring – Above Green

Minimum standard (credits available building type dependent)

Aim

To recognise and encourage the installation of energy sub-metering that facilitates the monitoring of operational energy consumption.

Assessment criteria

Please note:

The first credit is applicable to all building types.
The second credit is not applicable to preschools, primary schools, law courts, prisons, multi- residential and other buildings: residential institutions.

The following is required to demonstrate compliance:

One credit - Sub-metering of major energy-consuming systems

Energy metering systems are installed that enable at least 90% of the estimated annual energy consumption of each fuel to be assigned to the various end-use categories of energy-consuming systems (see Methodology ).

The energy-consuming systems in buildings with a total useful floor area greater than 1,000m² are metered using an appropriate energy monitoring and management system.

The systems in smaller buildings are metered either with an energy monitoring and management system or with separate accessible energy sub-meters with pulsed or other open protocol communication outputs, to enable future connection to an energy monitoring and management system (see Relevant definitions ).

The end energy-consuming uses are identifiable to the building users, for example through labelling or data outputs.

One credit - Sub-metering of high energy load and tenancy areas

An accessible energy monitoring and management system or separate accessible energy sub-meters with pulsed or other open protocol communication outputs to enable future connection to an energy monitoring and management system are provided, covering a significant majority of the energy supply to tenanted areas or, in the case of single occupancy buildings, relevant function areas or departments within the building or unit.

5.a

In most circumstances, sub-metering should be per floor, or per floor plate where there are multiple service risers, cores, or floor plates.

5.b

It is possible to sub-meter per entire core or service riser, where the number of rooms served by the riser is less than the number of rooms on a typical floor (served by all risers).

5.c

In the instance of a number of service risers that each serve a large number of rooms on each floor in high-rise building; sub-metering by ‘floor plate’ which would mean sub-metering each of the three risers at each floor is preferable.

Checklists and tables

None.

Compliance notes

Ref	Terms	Description
Applicable assessment criteria
CN1	Part 1: Fabric and structure	This issue is not applicable
CN2	Part 2: Core services	All assessment criteria are applicable
CN3	Part 3: Local services	All assessment criteria are applicable
CN4	Part 4: Interior design	Criteria 1 to 4 are applicable
General
CN5	Extensions to existing buildings	Where the refurbishment project includes an extension, with building services plant and systems that will be common to both the new extension and existing building, the energy services supplying energy-consuming systems in the existing building shall, as a minimum, be metered. Where the scope of the assessment includes the new build extension (see 2.0 Scope of the BREEAM International Non-Domestic Refurbishment 2015 scheme section for guidance on assessment of new build extensions) energy metering must cover energy-consuming systems for the entire building.
CN5.1	Refurbishment of part of an existing building	Where only part of an existing building is being refurbished and there are existing building services plant and systems that will be common to both the refurbished part and the unchanged part of the building, the criteria only apply to the refurbished part. In this case, energy services supplying energy-consuming systems from the existing building services in the unchanged part shall, as a minimum, be metered at the entry points to the refurbished part, e.g. hot water, chilled water, gas and electricity. However, the best practice approach would usually be to ensure that the energy metering covers the entire building.
CN5.2	Modular boiler systems. See criterion 1 .	Modular boiler systems can be monitored as a whole. See Relevant definitions
CN5.3	Lighting and small power. See criterion 5 .	Due to traditional distribution methods, it can be difficult to separate lighting and small power cost effectively. It is acceptable, within a single floor, for lighting and small power to be combined for metering purposes, provided that sub-metering is provided for each floor plate.
CN5.4	Small function areas or departments. See criterion 5 .	For a building consisting of a number of small function areas or departments, sub-metering the heating, hot water and combined electricity energy uses is sufficient to achieve this credit. Individual electricity energy uses within each unit do not need to be sub-metered. For the purpose of this BREEAM issue, a small function area or department is defined as less than 250m².
CN5.5	Heating and hot water. See criterion 5 .	Space heating and domestic hot water may be combined with a single heat or gas meter per tenanted area or function area or department, where it is impractical to sub-meter these items separately.
CN5.6	Significant majority. See criterion 5 .	A significant majority of the energy supply to the tenanted areas or function areas or departments covers most of the energy uses, but does not have to include very small ones. As a guide, energy uses that cumulatively make up less than 10% of the energy supply for that area may be excluded.
Building type specific
CN6	Buildings situated on campus developments. See criterion 5 .	The systems for buildings situated on campus developments must be monitored using either an appropriate energy monitoring and management system or another automated control system, e.g. outstations linked to a central computer, for monitoring energy consumption. The criteria only apply to the assessed building. Where energy services are supplied from an existing building on the campus, they shall be metered at the entry points to the assessed building, e.g. hot water, chilled water, gas and electricity. Provision of a pulsed or other open protocol communication output is not sufficient to award the credit for these building types.
CN6.1	Small tenanted office, industrial or retail units. See criterion 5 .	For a development consisting of a number of small tenanted units, a single meter per unit for electricity and another for heating is sufficient to achieve this credit. Individual areas within each unit do not need to be sub-metered. For the purpose of this BREEAM issue, a small unit is defined as less than 250m².
CN6.2	Large office, industrial or retail units. See criterion 5 .	For a development consisting of one or more larger units (i.e. greater than 250m²), sufficient sub-metering to allow for monitoring of the relevant function areas or departments within the unit must be specified, in addition to metering of the unit as a whole.
CN6.3	Healthcare buildings: medical-based systems See criterion 5 .	Large-scale medical equipment or systems can be excluded when assessing compliance with this issue (although it is recommended that sub-metering is considered in such instances).
CN6.4	Single occupant buildings: relevant function areas or departments. See criterion 5 .	The lists below summarise the commonly found functions by building types. These lists are not exhaustive and where other areas or departments exist, these should also be separately metered.
CN6.5	Office buildings	Office areas (metering by floor plate) Catering
CN6.6	Retail buildings	Sales area Storage and warehouse Cold storage Offices Catering Tenant units
CN6.7	Industrial units	Office areas Operational area Ancillary areas (e.g. canteens etc.)
CN6.8	Education buildings	Kitchens (excluding small staff kitchens and food technology rooms) Computer suites Workshops Lecture halls Conference rooms Drama studios Swimming pools Sports halls Process areas Laboratories High containment suites within laboratories Controlled environment chambers Animal accommodation areas Data centres IT work and study rooms, including IT-equipped library space and any space with provision of more than one computer terminal per 5m². Individual sub-metering of standard classrooms or seminar rooms is not required.
CN6.9	Hospitals and other healthcare facilities	Operating departments Imaging departments Radiotherapy departments Pathology departments Dialysis departments Medical physics facilities Mortuary and post mortem departments Rehabilitation when including hydrotherapy pools Central sterile supplies departments (or equivalent) Process areas, e.g. commercial-scale kitchens and laundries IT rooms Pharmacy departments Laboratories Tenancy areas (e.g. catering, retail, laundry) In small healthcare buildings (< 999m²) with no high energy load areas (as defined above), a single meter per floor plate is sufficient to achieve this credit. Individual areas within each floor plate do not need to be sub-metered.
CN6.10	Other buildings. See criterion 5 .	Other types of single occupant buildings should use the above lists of function areas as a guide to the level of provision required to comply, bearing in mind the aim of the credit is to encourage the installation of energy sub-metering that facilitates the monitoring of in-use energy consumption (in this case by area).

Methodology

Metering strategy

Detailed guidance on how to develop an appropriate metering strategy for the energy criteria of a building is available in General Information Leaflet 65: Metering energy use in new non-domestic buildings and CIBSE TM39 Building energy metering1.

Estimating the annual energy consumption of each end-use

Where the total consumption of any single end-use category (or a combination of end-use categories added together) is estimated to account for less than 10% of the annual energy consumption for a given fuel type, it is not necessary for this end-use to be sub-metered. In this instance, the design team should demonstrate that the respective end-uses are expected to account for less than 10% of the annual energy consumption for the fuel type. Where a given end-use will clearly account for less than 10% of the total annual energy consumption for the fuel type in question, a simple hand calculation or use of benchmark data to demonstrate this is acceptable.

Estimating the total annual energy consumption

Where it is unclear whether an end-use would account for 10% of the annual energy consumption for a given fuel type or not, more detailed calculations should be provided. The total annual energy consumption should be estimated using a method that estimates actual energy consumption. The energy consumption for each end-use may be estimated by using methods described in CIBSE TM54: Evaluating operational energy performance of buildings at the design stage2, using actual operational inputs. The weather data used should be the average current weather data for the local area from a credible and verifiable source (e.g. a regional, national or international meteorological organisation, data source or equivalent). The data on water consumption from the Wat 01 Water consumption issue may be used as inputs for evaluating the energy use of domestic hot water.

Alternatively, where present, energy metering data for the existing building may be used to estimate total annual energy consumption for the refurbished building, provided the metered data accounts for the total annual energy consumption from all energy-consuming systems.

Evidence

Criteria	Interim design stage	Final post-construction stage
All	One or more of the appropriate evidence types listed in 4.0 The BREEAM evidential requirements section can be used to demonstrate compliance with these criteria.

Additional information

Relevant definitions

Accessible meters

Energy meters located in an area of the building that allows for easy access to facilitate regular monitoring and readings by the building occupants or facilities manager. Typically this will be the plant room, main distribution room or control room (where a building energy management system (BEMS) is installed).

Common areas

Developments that have several tenant units, particularly large retail developments, may also share common facilities and access that is not owned or controlled by any one individual tenant, but used by all. Common areas are typically managed and maintained by the development's owner, i.e. landlord or their managing agent. Examples of common areas include an atrium, stairwells, main entrance foyers or reception or external areas, e.g. parking.

Energy-consuming systems

Systems that consume energy to perform the following functions (where present) within a building:

Space heating
Domestic hot water heating (excluding small 'point of use'. water heaters)
Humidification
Cooling
Ventilation, i.e. fans (major)
Pumps
Lighting
Small power (lighting and small power can be on the same sub-meter where supplies are taken at each floor, core or floor plate)
Renewable or low carbon systems (separately)
Controls
Other major energy-consuming systems or plant, where appropriate. Depending on the building type, this might include for example: plant used for swimming or hydrotherapy pools; other sports and leisure facilities; kitchen plant and catering equipment; cold storage plan; laboratory plant; sterile services equipment; transport systems (e.g. lifts and escalators); drama studios and theatres with large lighting rigs; telecommunications; dedicated computer room or suite; dealing rooms; covered car parks; ovens or furnaces; and floodlighting. See also CIBSE TM39: Building energy metering and General Information Leaflet 65: Metering energy use in new non-domestic buildings for further information.

Energy meters

Energy meters measure the amount of energy used on a circuit where energy is flowing. Primary meters measure the main incoming energy and are used for billing by the utility supplier. They include the principal smart and advanced utility meters to a site for electricity and gas.

Sub-meters are the second tier including heat and steam meters and secondary meters installed to measure consumption by specific items of plant or equipment, or to discrete physical areas, e.g. individual buildings, floors in a multi-storey building, tenanted areas, function areas.

Energy monitoring and management system

Examples include automatic meter reading systems (AMR) and building energy management systems (BEMS). Automatic monitoring and targeting (a M&T) is an example of a management tool that includes automatic meter reading and data management.

Energy supply

All types of energy supplied to a building area (function area or department or tenancy or unit) within the boundary of the assessed development; including electricity, gas, heat or other forms of energy or fuel that are consumed as a result of the use of, and operations within, each relevant area.

Major fans

Major fans typically include fans in air handling units (AHUs). Where multiple fans are within an air handling unit, they can be metered as one unit. Small fans such as individual extract fans for single rooms, such as kitchen, bathroom and toilet areas, are not required to be included where they only account for a small proportion of the total annual energy use.

Modular boiler systems

A modular boiler system consists of a series of boilers that are linked together to meet a variety of heating demands. They are generally composed of several identical boiler units, sometimes stacked, although a mix of condensing and conventional boilers could be used. They operate in increments of capacity, each at around their full capacity and their peak efficiency, so that the overall part load efficiency is greater than it would be for a single boiler.

Sub-meter outputs

Examples include pulsed outputs and other open protocol communication outputs, such as Modbus.

Other information

None.