Metering requirements

The use of accurate and reliable electricity meters producing high-quality, verifiable data is fundamental to the integrity of the Large-scale Renewable Energy Target (LRET).

Applicants seeking power station accreditation must demonstrate that electricity meters installed at the power station meet large-scale generation certificate (LGC) eligibility requirements under the Renewable Energy (Electricity) Act 2000.

The Clean Energy Regulator adopts a pragmatic, risk-based approach to metering requirements for the measurement of electricity generation for use in the general formula. Accordingly, the requirements for metering installations and application of relevant National Electricity Market (NEM) standards are dependent on factors such as the point of measurement, volumes of electricity flow, power station configuration and operating characteristics.

Electricity meters must be installed at the point that electricity is despatched from the power station or delivered as useful electricity to an external load. The Clean Energy Regulator's requirements apply at the point of settlement for Market Registered Generators to measure electricity production and auxiliary loss. The requirements also apply to sub-meters used for LGC calculation purposes for embedded generators such as rooftop solar.

Measuring distributed or transmitted electricity (DLEG)

To be eligible for accreditation under the LRET, power stations in the NEM must use NEM standard metering as defined in the National Electricity Rules (the Rules) for their connection point meter. For power stations outside the NEM, the power station must use metering that enables the Clean Energy Regulator to determine the amount of electricity generated by the power station, meets relevant jurisdictional standards, and is located at the point determined by the relevant authority in that State or Territory. These meters support the measurement of sent out electricity (or DLEG).

While DLEG is not generally reported to the Clean Energy Regulator, data from these meters can be acquired through the Clean Energy Regulator's data sharing arrangement with the Australian Energy Market Operator (AEMO) to test whether power stations are correctly calculating their electricity generation and corresponding LGC entitlement.

Measuring electricity production (TLEG)

For the measurement of electricity production (i.e. TLEG), power stations are expected to use metering installations for all generator terminals that conform to relevant standards from Chapter 7 of the Rules, set out below. These standards only apply to sub-meters used for LGC calculation purposes – power stations using connection point meters to measure electricity production and auxiliary loss must use meters fully compliant with all aspects of t​he Rules.

Relevant standards for sub-metering installations measuring electricity production:

• have either a visible or an equivalently accessible display of the cumulative total energy measured by that meter
• be accurate in accordance with the requirements in Schedule 7.4 of Chapter 7 of the Rules, in particular Table S7.4.3 (accuracy requirements for metering installations)
• be secure and that associated links, circuits and information storage and processing systems are protected by appropriate security mechanisms
• meet relevant Australian Standards and international standards identified in the Rules
• have electronic data transfer facilities to enable transmission of energy data to a third party
• include a communications interface to enable remote acquisition of energy data
• record energy data in a manner that collates the amount of active energy and reactive energy (where relevant), in intervals equal to at least every 30 minutes
• be capable of separately recording energy data for energy flows in each direction where bi-directional active energy flows occur or could occur
• has a measurement element for active energy and if required, reactive energy, with both measurements to be recorded, and
• include facilities for storing interval energy data for a period of at least 35 days.

If proposed meters differ from these requirements, you will be able to make a case in your application for accreditation as to how those meters accurately determine the amount of electricity generated by the power station. Meters need to provide measurements of a level of accuracy and quality that enables the Clean Energy Regulator to determine the eligibility of LGCs created based on those measurements.

In practice, power stations measuring electricity flows of greater that 750 MWh per annum use revenue-grade, pattern approved metering at these sub-metering points. These have the capability required to accurately measure the volumes of electricity production associated with these power stations.

The Clean Energy Regulator may request nominated persons to demonstrate that metering installations are compliant with these standards through our audit framework or through requests for meter testing.

Calculating auxiliary loss (AUX)

Power stations must demonstrate how the amount of auxiliary loss and imported electricity (i.e. AUX) is accounted for in the general formula. Auxiliary loss is electricity used in generating electricity and operating and maintaining the power station, but does not include any electricity used for network control ancillary services. The metering of auxiliary loss by a meter meeting the requirements set out above is considered the most accurate method of measuring the amount of auxiliary loss.

The Clean Energy Regulator may accept alternative methods to calculate auxiliary loss in circumstances where metering is not appropriate or would result in inaccurate measurement. In these cases, the power station must demonstrate how the alternative method provides an equivalent auxiliary electricity amount. The decision on whether to accept a calculated auxiliary takes into consideration factors such as the configuration of the power station, volumes of electricity flow and fuel source.

Measuring ineligible energy sources (FSL)

Power stations using an ineligible fuel source for the generation of electricity should use meters meeting the same requirements for electricity production (TLEG). If electricity generation for ineligible fuel sources cannot be separately metered, FSL is calculated by converting the energy content of these energy sources into the equivalent number of MWh of electricity.

Temporary variations

The Clean Energy Regulator may accept temporary variations to the method of calculating electricity generation where data from meters is not available due to unforeseen issues such as meter failures or disruptions to data access. In these cases, metering systems not meeting these standards (such as data from inverters in solar photovoltaic systems) may be used to support LGC eligibility.

Applications to vary a LGC methodology may be made through the REC Registry.

The variation to LGC methodology may consider any reductions in accuracy in measurement from these devices. The use of such devices will only be permitted on a temporary basis and efforts to rectify metering must be undertaken within reasonable timeframes (e.g. no longer than three months).