Electricity Metering

Energy, in recent years has emerged as a major challenge for the 21st Century business. With rapidly escalating energy costs, which could damage profits or seriously erode budgets....


Energy, in recent years has emerged as a major challenge for the 21st Century business. With rapidly escalating energy costs, which could damage profits or seriously erode budgets, coupled with a growing concern about global climate change, air pollution and depletion of nonrenewable resources, there is a clear need for prudent management of energy consumption.

Additionally, there are a number of legislative requirements, that means metering is and will be required to understand the use of energy throughout a building.

This is achieved through energy monitoring & management, thereby helping to save money, optimise energy usage and re-duce the impact on the environment.

The purpose of this report is to provide a summary of the current and forthcoming requirements for metering and metering systems to enhance energy performance and its impact on the environment.

Primary Metering

We are used to a meter at the point of delivery, for electricity, gas and more frequently now for water. This meter records the amount of consumption at the point at which the utility enters the building or area.

These meters are known as Primary Meters and are generally owned and operated by a Meter Operator. However, in most cases the Customer can opt to own the meter themselves and then contracting an Operator to carryout the Registration, Operation and Maintenance under Regulatory conditions. Therefore, these Operators have to be Approved and work within various Codes of Practice. The Meters also have to meet a set criteria under Codes of Compliance. These Codes lay down the specification of Accuracy, Parameters of Recording information or data, type of data retrieval & how long that meter can stay on circuit.

The larger the supply the more accurate they have to become, and as such Electricity Metering Codes of Practice (CoP) fall into bands of Demand, as follows:

  • CoP 1 >100MW
  • CoP 2 >10MW up to 99.9MW
  • CoP 3 >1MW up to 9.99MW
  • CoP 5 >100kW up to 999.9kW
  • CoP 4 is the Code of Practice for
  • the installation of Code Compliant

Each of these systems records and stores data in half hour intervals in line with the UK Electricity Trading markets. This data is retrieved each day remotely across either fixed telephone lines (PSTN) or mobile modem (GSM) or radio pad (PAKNET), by the Data Collector, who is accredited through the Regulatory system. All other Primary metered demands are measured using Non- Half Hourly Metering, where the register or dial advances as power is consumed and a manual reading is taken from this register at set intervals.

Primary meters are then used by your Supplier to Invoice for Electricity consumed. There are proposals to bring down the demand levels where Half Hourly metering is installed, and when the new rules apply will mean that mandatory Half Hourly metering will need to be installed. These proposals (still at consultation stage, although should have been implemented at the beginning of 2009) will mean that the following Load Factors (LF) apply:

  • Profile Class 05 0%-20% LF
  • Profile Class 06 20%-30% LF
  • Profile Class 07 30%-40% LF
  • Profile Class 08 >40%

These Profile Classes can be obtained from the MPAN on the Electricity Invoices.

If the Customer is a participant in the Carbon Reduction Commitment (CRC) scheme, the installation of these meters will also contribute towards the 90% of a CRC Organistion's direct emissions.

Generally, these Primary meters also have the ability to accept up to 2 pulsed inputs, that allow you to use the memory within the Primary meter to record and count pulsed outputs from other metering systems, for instance Gas & Water meters.

Approval is required from the Meter Operator.

Therefore, this allows the Customer to have a reasonably priced multi-utility collection solution, piggy backing on the existing communications device.

Secondary Metering

Where Primary Metering is recording consumption at the point of delivery to the building or area, Secondary Metering is recording the consumption of various supply points within that building or area.

Most Secondary Meters are installed to record the large consuming pieces of plant to breakdown where energy is being used or identify where it is being wasted.

Under Part L of the Planning Regulations ADPL2A, 90% of a new buildings consumption is required to be metered, and under ADPL2B where an existing building or plant is being extended, then it too should be metered.

There are many ways in which to set up a secondary or sub metering scheme.

The first method would be to install simple nonhalf hourly meters that advance as the meters records consumption. To install this type of meter the capital cost is reasonably priced. However, this method means that you need to manually record the meters on a regular basis, either weekly or monthly, but can experience reading errors, variable read intervals and can be quite costly in man-hours retrieving the data .

A better option is to install half hour meters with the ability to have its data retrieved remotely, thereby cutting down on reading errors, saving the labour in sending someone to read the meters and improving the interval times which allows greater evaluation of consumption patterns. Equally, these Half Hour meters have the advantage of being time synchronised with the main incoming Primary meter. There is also the advantage of selecting metering equipment that is part of the Enhanced Capital Allowance scheme, and thereby improving the tax efficiency of the scheme.

These meters are connected to a network to allow the meter to talk to the central collection system, that can generate Performance data and identify improvement areas and in turn cost reductions.

There are a number of ways in which to communicate with your metering system. Wireless options are available, and are quick to install, but do experience reliability issues in retrieving data within buildings on occasions due to interference.

Generally, we find that a hard wired network linking all the meters is the optimum solution as, data retrieval is more reliable, fault finding on the network is easier in future years and cheap to repair and add onto.

Glossary of Terms:

  • ADPL2A Approved Document Part L2A
  • ADPL2B Approved Document Part L2B
  • CoP (Code of Practice)
  • HH (Half Hourly)
  • LF (Load Factor)
  • MPAN (Meter Point Administration No.)
  • NHH (Non-Half Hourly)
  • PC (Profile Class)