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Department for Business, Energy and Industrial Strategy

Automatic Monitoring & Targeting (aM&T) Sub-metering Systems

1.1           Scope

Automatic Monitoring & Targeting (aM&T) sub-metering systems are products that are specifically designed to measure energy consumption, record and distribute metered energy data, and analyse and report on energy consumption.

1.2           Definitions

aM&T sub-metering systems help users to save energy by identifying energy wastage which they can then take steps to reduce. aM&T sub-metering systems generally comprise of three elements:

  • Sub-metering & sensors
  • Communication and data capture software, and;
  • Monitoring software.

Fiscal metering and internet-based software are outside the scope of this category.

An aM&T sub-metering system captures energy consumption information automatically from which users can gain an understanding of their organisation’s energy use. It consists of equipment components that measure, record, transmit, analyse, report and communicate the energy management information that an organisation needs to manage its energy use (i.e. through implementing an effective energy management system) and highlight any energy wastage.

A wide range of aM&T sub-metering systems are available. The Energy Technology List (ETL) aims to encourage the installation of sub-metering systems that can facilitate the proactive management of energy use in organisations.

Eligible aM&T sub-metering systems shall comply with the requirements as set out below. The individual equipment components or products used in the system do not need to be named on the ETL.

1.3           Requirements

1.3.1       Eligibility requirements 

To be eligible, aM&T sub-metering systems shall

1.    Include the following:

a)    One or more meters that measure energy use for metering purposes.

b)    Some means of automatically capturing, retrieving & storing energy metering data electronically.

c)     Software that enables the analysis of energy metering data and the key factors that influence energy use by means of visualising energy performance data.

2.    Be able to meter at least one of the following:

a)    Electricity use

b)    Gas use

c)     Heat use

The following sub metering equipment and sensors are eligible but only as part of an aM&T sub-metering system that directly measures at least one of the parameters in section 2a-c (above):

  • Oil fuel flow meters
  • Compressed air mass flow meters
  • Steam meters

3.    Additionally, for electricity, gas and heat meters, the system shall be able to:

  • Automatically capture data from meters or sensors at regular intervals in order to provide energy performance indicators. The collection intervals may be user definable or configured for particular meter types.
  • Store and process meter readings made on a half hourly basis (as a minimum). The metering data may be transferred into the data store in real-time or at scheduled times.
  • Automatically identify and report data collection failures, missing metering data and the failure of communications with meters, transducers and any other system components.
  • Distribute data with no loss of accuracy, except for pulse outputs from meters, where the transmitted metered data shall be within +/- 0.5 % of the total variable measured.
  • Present energy consumption data in graphical reporting formats (for example, histograms, line plots, etc.), and in user selectable time intervals / divisions / bases.
  • Export the collected energy data in a standard format for use in other applications (for example, ASCII files or other formats commonly used by standard office applications).
  • Retain a minimum of 2 complete years of metering data without loss of data resolution or accuracy, in a date/time stamped format, suitable for analysis of trends and patterns.

4.    For electricity, gas and heat meters, the system shall provide facilities to enable the user to:

  • Select datasets from individual meters and manipulate them by combining, comparing and calculating in order to analyse, identify and evaluate instances of energy waste.
  • Undertake regression analysis using two variables in whatever frequency the dataset was obtained, and to display the results in graphical form with a correlation coefficient.
  • Set up automatic exception reporting functions that are capable of basing exception reports on the raw data profile. The frequency capability of notifications should be kept at a minimum.
  • Set up standard management reports that enable total energy consumption to be benchmarked against performance standards during a user selectable period. It may also be beneficial to compare energy consumption with the corresponding period in the previous year, including an analysis of energy use by meter, fuel type or energy accounting centre.

In addition, where new meters are being installed, they shall comply with the following requirements:

5.    Electricity meters shall meet the accuracy requirements of one of the following:

  • BS EN62053-21:2003, “Electricity metering equipment (ac) – Particular requirements - Part 21: Static meters for active energy (classes 1 and 2)”.
  • BS 8431:2010, “Electrical static metering for secondary or sub-metering. Specification” (BSI, ISBN 0 580 451178). Classes 1 or 2.

6.    Gas meters shall meet the accuracy requirements of one of the following standards:

  • BS EN12261:2002, Gas Meters - Turbine gas meters.
  • BS EN12480:2015, Gas Meters - Rotary displacement gas meters.
  • BS EN1359:1999, Gas Meters - Diaphragm gas meter.

7.    Heat meters shall meet the requirements of:

  • BS EN 1434-1: 2015, Heat meters. General requirements.
  • BS EN 1434-4: 2015, Heat meters. Pattern approval tests
  • BS EN 1434-5: 2015, Heat meters. Initial verification tests

8.    Oil fuel flow meters shall conform to the following requirements:

  • Be installed on the same aM&T submetering system as either an electricity, gas or heat meter.
  • The Measuring Instruments Regulations 2016 (Schedule 1, Section 7)[1].
  • Possess a minimum flow rate range of 4:1, where the flow rate range is defined as the range between the minimum flow rate (Qmin) and the maximum flow rate (Qmax).
  • The accuracy classification and Maximum Permissible Error (MPE) as defined within The Measuring Instruments Regulations 2016 (Schedule 1, Section 7)[2].

9.    Compressed air mass flow meters shall conform to the following requirements:

  • Be installed on the same aM&T submetering system as either an electricity, gas or heat meter.
  • The Measuring Instruments Regulations 2016 (Schedule 1, Section 7)[3]. ​​​

10. Steam meters shall conform to the following requirements:

  • Be installed on the same aM&T submetering system as either an electricity, gas or heat meter.
  • Be capable of displaying the measured steam pressure and temperature, and the current mass flow rate and cumulative mass of steam
  • Shall have, as a minimum, the following components continuously measuring the steam properties and calculating the cumulative steam energy that has passed through the measuring system as shown on the system’s schematic diagram:
  • A flow meter – which determines how much fluid (steam) has passed through a pipe over a given time period
  • A pressure sensor – to measure the pressure of steam flowing through the pipe
  • A temperature sensor – to measure the temperature of steam flowing through the pipe
  • A calculator/digital integrator – which uses the information provided by the flow meter, temperature and pressure sensors to calculate the cumulative heat energy transferred through the pipe.
  • Conformity with the requirements of the appropriate BS EN ISO 5167 series of standards, if relevant for the steam meter
  • 11. Instrument transformers used to measure energy use for metering purposes shall conform to the Class 1 accuracy requirements of one of the following:
  • BS EN 61869-2:2012, “Instrument transformers. Additional requirements for current transformers”.
  • BS EN 61869-3:2011, “Instrument transformers. Additional requirements for inductive voltage transformers”.

Meters offering equivalent or better levels of accuracy to those specified above will be accepted, provided they meet the accuracy requirements of applicable British. Please note that this includes all electricity, gas and heat meters conforming to the specific accuracy requirements of The Measuring Instruments Regulation 2016.

1.4           Verification for ETL Listing

This sub-technology is “unlisted” therefore individual products do not need to be listed on the Energy Technology Product List.

1.5           Conformity testing

Products listed on the ETL may be subject to the scheme’s conformity testing programme in order to ensure listed models continue to meet the ETL requirements.

[1] Annex I of the Measurement Instrument Directive (EC No. 2014/32/EU)

[2] Section 2 of Annex VII (MI-005) of the Measurement Instrument Directive (EC No. 2014/32/EU)

[3] Annex I of the Measurement Instrument Directive (EC No. 2014/32/EU)