1. Can a power station be interstate?

2. Who is eligible to apply for accreditation for a generating system?

3. Is an embedded power station supplying generation to an on-site end-user eligible?

4. Can a renewable power station create RECs and NGACs for the same MWh of generation?

5. How is coal seam methane gas treated, as opposed to waste coal mine gas, within GGAS?

6. How are landfill gas and sewage gas generating systems treated, as opposed to bio-digester generating systems, within GGAS?

7. How does the cogeneration adjustment work?

8. At what stage should I apply for accreditation if I am planning to undertake efficiency improvements to my generating system?

9. Does GGAS accredit planned for, but as yet unbuilt, generation projects?

1. Can a power station be interstate?

Potentially, any generating system operating within the National Electricity Market (NEM - currently comprised of Queensland, NSW, ACT, Victoria and South Australia) is eligible to apply for accreditation under the Generation Rule. The chief test of eligibility being whether the generating system physically exports electricity to the NEM via connection to, or interconnection with, a registered distribution or transmission network connected to the NSW electricity network. Refer to clause 5.2 of the Generation Rule for further information.

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2. Who is eligible to apply for accreditation for a generating system?

Essentially, the ‘Generator’, as defined in clause 6.2.1 of the Generation Rule, is either the person registered with the National Electricity Market Management Company (NEMMCO) as the Generator or Intermediary for that generating system, or if no such person is registered, the owner of the Generating System.

However, in the case of Category A generating systems the ‘Deemed Retailer’ (as defined in clause 6.3.1 of the Generation Rule) is also eligible to apply for accreditation.

Additionally, a person may be nominated (to the satisfaction of the Scheme Administrator) by the respective Generator or Deemed Retailer identified above. In this case, the nominated party is then entitled to apply for accreditation.

Refer to the Guide to Applying - Generation Rule for examples of nomination forms approved by the Scheme Administrator.

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3. Is an embedded power station supplying generation to an on-site end-user eligible?

Only generation directly exported to the National Electricity Market (NEM) is eligible under the Generation Rule. Therefore, if only a small component of an embedded generating system’s generation is exported directly to the NEM, only this component of generation is eligible to create abatement certificates under the Generation Rule. If, however, the remainder of the generation is supplied to an on-site end-user via a private (un-registered) network, then this generation may instead be eligible to create abatement certificates under clause 12 of the Demand Side Abatement Rule. The main proviso being, that the entitlement to create abatement certificates for the on-site component of generation is limited to that occurring in NSW. That is, interstate demand side abatement activity is not recognised under GGAS.

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4. Can a renewable power station create RECs and NGACs for the same MWh of generation?

If a renewable fuel generating system is creating a Renewable Energy Certificate (REC) for a MWh of greenhouse gas emission abatement (under the Commonwealth’s Mandatory Renewable Energy Target), it is ineligible to create a NSW Greenhouse Abatement Certificate (NGAC) for the same MWh of abatement. Refer to clauses 73HA, 73IA and 73IB of the Electricity Supply (General) Regulation 2001 for further information.

However, if the generating system uses landfill gas, sewage gas, manufactured methane, or waste methane from other renewable energy sources as its fuel for electricity generation, it may be eligible to create ‘additional NGACs’ in recognition of the fugitive methane emissions avoided through this generation activity. Refer to clause 9.5 of the Generation Rule for further information.

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5. How is coal seam methane gas treated, as opposed to waste coal mine gas, within GGAS?

  Under GGAS, coal seam methane and waste coal mine gas are treated differently when used as fuel for generation activities, although their geological genesis is identical.

The reason for this different treatment stems from the fact that coal seam methane gas per se would be geologically ‘locked-up’ if not for its extraction and production. As such it is treated as natural gas and creates abatement certificates on the basis of its lower emissions intensity (when compared to that of the NSW pool coefficient).

On the other hand, coal seam methane which is liberated from geological ‘enclosure’ as a function of mining activity is seen to be a fugitive greenhouse emission, if not for its capture and combustion in the form of waste coal mine gas. As such, waste coal mine gas receives an additional benefit (in terms of the number of abatement certificates created per MWh of generation) in recognition of the fugitive methane emissions avoided (methane having a global warming potential 21 times that of carbon dioxide).

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6. How are landfill gas and sewage gas generating systems treated, as opposed to bio-digester generating systems, within GGAS?  

Despite possibly having similar fuel sources for the derivation of its resultant methane gas, landfill gas and sewage gas fuelled generating systems receive a slightly different treatment under the Generation Rule, than generating systems using ‘manufactured methane’ as fuel (such as bio-digesters).

The treatment differs on the basis that generation from landfill gas and sewage gas derives its energy from existing waste disposal methods (and accordant waste stream inputs) that have historically released (and in some cases, may continue to do so) fugitive methane emissions to the atmosphere. As such, these types of generating systems utilise Equation 16 of the Generation Rule to calculate the amount of fugitive methane emissions directly avoided through the use of the fuel.

On the other hand, bio-digesters are seen as diverting existing waste streams (that may possibly have been disposed of via less intensive methane formation methods than bio-digestion), thus in effect, ‘artificially’ creating methane emissions in excess of those which would have ‘naturally’ occurred (if existing disposal methods such as windrows, anaerobic lagoons or landfill had been used). As such, these types of generating systems utilise Method 5 of the Generation Rule to calculate the amount of nominal fugitive methane emissions directly avoided through the use of the fuel. In most cases, but not necessarily all, the amount of notional fugitive methane emissions avoided using Method 5 will be less than if it was able to be calculated using Equation 16. However, this treatment reflects an overarching Government policy not to reward the manufactured creation and subsequent destruction of methane, above that which would occur using existing disposal methods.

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7. How does the cogeneration adjustment work?

Where a generating system makes use of its waste heat to replace an existing fossil fuel derived heat source at an adjacent process or activity, the generating system is able to adjust its total greenhouse gas emissions in recognition of the notional greenhouse gas emissions avoided.

For example, if a landfill gas fuelled generating system supplies its waste heat to a nearby swimming pool that previously used a natural gas fired boiler to provide its heat supply, the generating system’s waste heat is effectively replacing emissions associated with the use of natural gas. As such, the total greenhouse gas emissions for the generating system are adjusted downwards by the accordant notional emissions avoided, resulting in a reduced emissions intensity for the generating system and an accordant increase to abatement certificates created.

If, however, the waste heat is used to replace a heat supply that was previously provided by renewable energy, the cogeneration benefit is zero.

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8. At what stage should I apply for accreditation if I am planning to undertake efficiency improvements to my generating system?

Under the Efficiency Improvement Approach, a generating system may create abatement certificates in recognition of improvements made after 1 January 2002 to its efficiency of generation. These improvements may be in the form of:

• Non-design improvements to efficiency, such as fine tuning of operational controls and improved maintenance procedures, known as Method 1 – GES Gain. To utilise this approach, the generating system must be a participant in the Commonwealth’s Generator Efficiency Standards program.
• Changes to the design of the generating system, but not its fuel mix, such as turbine upgrades, known as Method 2 – Performance Improvement Gain.
• Changes to the fuel mix, known as Method 3 – Fuel Switch Gain.

In utilising any of the above three Efficiency Improvement Approach methods, the Scheme Administrator strongly recommends that project proponents contact the Scheme Administrator to discuss their intended approach(es), prior to submission of an application for accreditation. This is especially the case if the project proponent intends to utilise Method 2 – Performance Improvement Gain.

Specifically, in utilising Method 2 of the Generation Rule, a project proponent must prepare and implement a Performance Improvement Testing Regime (acceptable to the Scheme Administrator) prior to making any design changes to the generating system. As such, it is imperative that the Scheme Administrator be contacted (and an application subsequently submitted) sooner, rather than later, to allow sufficient time for the Scheme Administrator to assess and approve the proponents testing methodology, prior to the actual testing taking place.

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9. Does GGAS accredit planned for, but as yet unbuilt, generation projects?

Following June 2004 amendments to the Electricity Supply (General) Regulation 2001 and the Generation and Demand Side Abatement Rules, GGAS now accepts applications for accreditation from proponents of future generating systems, known as Future Projects.

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