Delays to NEM connections and accurate forecasts

AEMO is currently consulting on its methodology for reliability forecasting in the NEM, and among their proposed changes is an adjustment to the inclusion of projected new capacity. The existing assumptions are being examined due to two factors;

  1. Most new connections in the NEM assume that the time taken to progress from ‘Committed’ status to being fully in service would take on average 150 days, while the observed actual time was 576 days. This discrepancy of 426 days means forecasts like the ESOO significantly over-forecast capacity in the short term.[1]
  2. The ESOO does not include projects further behind in the development cycle as their connection is not certain as far as the existing criteria go. However, it is rare for these projects to not eventually make it to market, resulting in a long-term under-forecast of capacity.

To compensate for this, AEMO has proposed applying the following:

  • A 6-month delay to all projects that have been granted ‘Committed’ status and have not met their first commissioning hold point.
  • Including projects with ‘Anticipated’ status, while also applying a 12-month delay to the project’s full commercial use dates supplied by the participants.

In Figure 1, the capacity in the NEM (including the closure of Liddell in the imminent future) is compared with the forecast capacities from the last 4 major annual ESOO releases. The changes to ‘Anticipated’ timing aren’t significantly relevant in this timeframe, but the delays to ‘Committed’ units can be seen in the dotted lines. As highlighted in the chart, each dotted line, which has been adjusted for AEMO’s proposed methodology, is closer to the actual NEM capacity line than the original.


[1] https://aemo.com.au/-/media/files/stakeholder_consultation/consultations/nem-consultations/2022/reliability-forecasting-guidelines-and-methodology-consultation/nem-reliability-forecasting-guidelines-and-methodology-consultation-paper.pdf


Reflecting on these changes and comparing them with the actual capacity that has been observed in the NEM over the last 4 years, this change appears to be a step towards closer alignment between forecasts and reality. This means that reports like the ESOO provide more value to participants, more accurately showing the risks to reliability and the opportunities for new storage and generation assets.

Delays during the commissioning process are a known issue, and reforms like the Connections Reform Initiative are being implemented to help assets connect to the NEM, however for developers looking to connect, there is still uncertainty. This is where Cornwall Insight Australia can help, from providing accurate forecasts of potential revenues, understanding and communicating the content of reports that market bodies produce, bespoke models that can take significant infrastructure delays into account, and helping understand the connections process in the Australian energy markets.

Have you recently connected to the NEM or are you seeking to? Please tell us about your experiences! And if you have any questions, please feel free to reach out and we can discuss how Cornwall Insights can help you, contact enquiries@cornwall-insight.com.au.

To keep reading, please log in to your account

Related thinking

Energy storage and flexibility

R1 and L1 revving up the BESS revenues

In our ‘The VFF… Very Fast and Financially rewarding market so far’ Chart of the week, the two new contingency markets, the Very Fast raise contingency FCAS market and the Very Fast lower contingency FCAS, were analysed and demonstrated the high participation of big batteries along with VPPs and DERs....

Low carbon generation

An investigation into REZ capacity factors during Victoria’s dark doldrums

As the grid transitions to much higher levels of renewable penetration, the range of generation outcomes on any given day increases. The worst of these ranges are known as dark doldrums when there is a combination of poor conditions for wind and solar generation, usually a windless day in winter....

Commercial and market outlook

The VFF… Very Fast and Financially rewarding market so far

On 9 October 2023, 1pm (market time), we saw the start of two new contingency FCAS markets. The Very fast raise contingency FCAS market, and the Very fast lower contingency FCAS. Upon commencement of the VF FCAS market, a commissioning period of two weeks with an initial max requirement of...

Commercial and market outlook

Is the sun setting on utility solar?

The Federal Government has legislated emissions reductions of 43% below 2005 levels by 2030. Sourcing electricity from renewable technologies is fundamental to meeting this, with a much-publicised target of 82% renewables in the grid by 2030 – up from a current value of 38% over the last year. Fortunately, the...

Commercial and market outlook

The Very Fast FCAS market is about to commence – a look at a possible time-of-day profile for R1

On 9 October 2023, 1pm (market time), the dispatch of the new Very Fast (VF) FCAS market in the NEM will commence and will add two new markets for contingency FCAS, Raise 1 (R1) and Lower 1 (L1). AEMO has released a final industry go-live plan to keep track of...

Low carbon generation

“Ooh, a storm is threatening, My very [interconnection] today”: Can states utilise interconnection to share wind resources?

Penetration of renewables continues to dominate the energy news, as we saw renewables as a proportion of total demand reach new heights this week to a new record of ~70% penetration. In light of this continuing march toward a renewable-dominated grid (building on some analysis we did in Chart of...

Energy storage and flexibility

How long is the ‘Golden time of day’ for batteries?

A key part of the business case for grid-scale standalone batteries is the arbitrage opportunity between low daytime wholesale prices (when renewable energy generation from solar is plentiful) and high evening prices (when the sun goes down and household demand ramps up quickly). The share of battery revenue coming from...

Low carbon generation

MLF changes in NSW in the past decade

MLF, short for Marginal Loss Factor, represents the portion of electricity losses that occur along the transmission network between a connection point and the Regional Reference Node (RRN). Within the NEM, the MLF serves as a metric to quantify these losses along the network, playing a pivotal role in determining...