SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT SOUTH AUSTRALIAN ADVISORY FUNCTIONS

Transcription

1 SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT SOUTH AUSTRALIAN ADVISORY FUNCTIONS Published: July 2015

2 IMPORTANT NOTICE Purpose This report is prepared by the Australian Energy Market Operator (AEMO) for the South Australian jurisdiction under Section 50B of the National Electricity Law. The purpose of this report is to provide information about historical levels of generation and interconnector supply in the South Australian region of the National Electricity Market (NEM). This report has been prepared by AEMO using information available at 30 June 2015, unless otherwise specified. Disclaimer AEMO has made every effort to ensure the quality of the information in this publication but cannot guarantee its accuracy or completeness. It incorporates information provided to AEMO by third parties. Accordingly, to the maximum extent permitted by law, AEMO and its officers, employees and consultants involved in the preparation of this publication: make no representation or warranty, express or implied, as to the currency, accuracy, reliability or completeness of the information in this publication; and are not liable (whether by reason of negligence or otherwise) for any statements, opinions, information or other matters contained in or derived from this publication, or any omissions from it, or in respect of a person s use of the information in this publication. Acknowledgement AEMO acknowledges the support, cooperation and contribution of all participants in providing data and information used in this publication The material in this publication may be used in accordance with the copyright permissions on AEMO s website. Australian Energy Market Operator Ltd ABN info@aemo.com.au NEW SOUTH WALES QUEENSLAND SOUTH AUSTRALIA VICTORIA AUSTRALIAN CAPITAL TERRITORY TASMANIA

3 EXECUTIVE SUMMARY The 2015 South Australian Historical Market Information Report (SAHMIR) provides historical information on South Australian electricity generation and interconnector supply between South Australia and Victoria, focusing particularly on the last five financial years, to Comparison of to Key observations in the past year are: The total electricity generation from scheduled, semi-scheduled, and selected 1 non-scheduled South Australian market generators decreased by 3% (317 gigawatt-hours (GWh)). Table 1 and Figure 1 show the change in total generation, and generation by fuel type, in the past year. The increase in coal generation can, in part, be attributed to the changed operating regime of Northern Power Station. 2 Combined interconnector net imports from Victoria decreased by 5% (84 GWh). Rooftop photovoltaic (PV) estimated generation increased by 19% (140 GWh). Total greenhouse gas emissions increased by 2% (0.11 megatonnes of carbon dioxide equivalent (MtCO2-e)). Capacity factors for all wind farms are lower for than for , which correlates with less wind observed at wind farm sites. Table 1 South Australian electricity generation by fuel type (GWh), comparing to Fuel Type Change % Change Gas 5,533 4, % 4,098 4, % Coal 2,100 2, % Diesel % Total 11,734 11, % Other energy sources Interconnector net imports 1,673 1, % Rooftop PV % 1 Selected non-scheduled generators include all wind farms greater than or equal to 30 megawatts, and Angaston power station, as listed in Table 2. 2 Alinta Energy advised that Northern Power Station returned back to normal service in October This followed periods of withdrawal from April to September in 2013 and Source: AEMO Generation Information Pages. Available: Information/Generation-Information. Viewed 2 July AEMO

4 Energy generation (GWh) SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT Figure 1 South Australian electricity generation by fuel type (GWh), comparing to ,000 10,000 11,734 11, ,100 2,648 8,000 6,000 4,000 2,000 4,098 5,533 4,226 4, Gas Coal Diesel Other key points in the 2015 SAHMIR: Trends observed include: Net total interconnector imports into South Australia from Victoria have shown a general upward trend since , despite a small decrease in the past financial year. farm and rooftop PV capacities have grown significantly in the last 10 years, with rooftop PV rapidly increasing in the last five years (from 138 megawatts (MW) in to 671 MW in ). AEMO

5 CONTENTS EXECUTIVE SUMMARY 1 1. INTRODUCTION Background Information Generation map 6 2. HISTORICAL GENERATION Generation changes Generation share by fuel type Greenhouse gas emissions Capacity factors INTER-REGIONAL SUPPLY Annual interconnector flows Daily average interconnector flow patterns Flow duration curves LINKS TO SUPPORTING INFORMATION 28 MEASURES AND ABBREVIATIONS 29 Units of measure 29 Abbreviations 29 AEMO

6 TABLES Table 1 South Australian electricity generation by fuel type (GWh), comparing to Table 2 Historical energy generation for South Australian power stations (GWh) a 8 Table 3 South Australian generation and net interconnector imports (GWh) 9 Table 4 Historical Heywood Interconnector power flow 20 Table 5 Historical Murraylink Interconnector power flow 20 Table 6 Historical combined interconnector power flow 21 Table 7 Percentage of financial year having full utilisation of nominal import capacity 25 FIGURES Figure 1 South Australian electricity generation by fuel type (GWh), comparing to Figure 2 Location and capacity of South Australian generators 6 Figure 3 South Australian energy generation by fuel type 9 Figure 4 Registered capacity by fuel type, to Figure 5 Greenhouse gas emissions for South Australia per financial year 12 Figure 6 Financial year capacity factors for scheduled generators 14 Figure 7 Financial year capacity factors for non-scheduled and semi-scheduled wind farms 15 Figure 8 Summer capacity factors for scheduled generators 16 Figure 9 Winter capacity factors for scheduled generators 17 Figure 10 Summer capacity factors for non-scheduled and semi-scheduled wind farms 18 Figure 11 Winter capacity factors for non-scheduled and semi-scheduled wind farms 19 Figure 12 Total interconnector imports and exports 22 Figure 13 Combined interconnector daily 5-min average flow 23 Figure Heywood, Murraylink and combined interconnector daily 5-min average flow 23 Figure 15 Combined interconnector summer daily 5-min average flow (business days only) 24 Figure 16 Combined interconnector winter daily 5-min average flow (business days only) 24 Figure 17 Heywood Interconnector flow duration curves 26 Figure 18 Murraylink Interconnector flow duration curves 26 Figure 19 Combined interconnector flow duration curves 27 Figure 20 Interconnector flow as a percentage of interconnector capacity 27 AEMO

7 1. INTRODUCTION This report provides historical information on South Australian electricity generation and interconnector supply between South Australia and Victoria, focusing particularly on the last five financial years, to This report comprises: Chapter 1: Background information on the data analysed for this report, and a map of generators in South Australia. Chapter 2: Historical information for the last five years on South Australian generation, generation by fuel type, generation greenhouse gas emissions, and generation capacity factor. 3 Chapter 3: Historical information on interconnector flows between South Australia and Victoria over the last ten years, and average interconnector flow patterns and flow duration curves for the last three years. Chapter 4: Links to supporting information. Any discrepancy between data presented in the commentary of this report and the derived data is attributable to rounding errors in the tables and figures. The data that supports the tables and figures in this report is published on AEMO s website Background Information The SAHMIR reports on electricity generated by power plants that operate in the National Electricity Market (NEM). These are typically greater than or equal to 30 MW registered capacity and are listed in Table 2. In addition, Section 2.2 of this report includes data from smaller embedded (non-scheduled) power plants. This provides a more complete representation of total energy generated, and generation capacity by fuel type, in South Australia. This data is gathered from the Market Settlements and Transfer Solutions (MSATS) system, and is aggregated to ensure anonymity of individual generators output. Historical estimates of rooftop PV generation are taken from the National Electricity Forecasting Report (NEFR) 5, to illustrate the impact on reducing operational NEM consumption 6. Figures displaying average daily interconnector flow and duration curves use 5-minute power flow data, measured in MW, to give a representation of peaks and changes over time. For generator output or interconnector flow analysed over a financial year or season, 5-minute power generation or flow data is aggregated and converted to an equivalent energy amount (measured in GWh). 3 Capacity factor is a ratio (expressed as a percentage) of the actual output of generating systems over a period of time, compared to the maximum possible output during that time. 4 Available at: Report. 5 AEMO. National Electricity Forecasting Report (NEFR). Available at Forecasting-Report. Viewed: 24 July Annual operational consumption is the electrical energy supplied by scheduled, semi-scheduled, and significant non-scheduled generating units. Annual operational consumption does not include the electrical energy supplied by small non-scheduled generating units. AEMO

8 1.2 Generation map Figure 2 shows the location and nameplate capacity of South Australian scheduled, semi-scheduled and significant non-scheduled generators. Figure 2 Location and capacity of South Australian generators AEMO

9 2. HISTORICAL GENERATION 2.1 Generation changes Table 2 sets out the energy generated from scheduled, semi-scheduled, and selected non-scheduled South Australian market generators from to Small non-scheduled generator data is not included here, but is addressed in the analysis in Section 2.2. Table 3 summarises the data in Table 2 alongside the net interconnector imports into South Australia from Victoria (via the Heywood and Murraylink interconnectors), as well as the estimated rooftop PV generation 7 in South Australia. It highlights the following key changes that occurred from to : Total generation from South Australian power stations (excluding rooftop PV) decreased by 3% (317 GWh). Total gas generation decreased by 18% (992 GWh). Total wind generation increased by 3% (128 GWh). Total coal generation increased by 26% (548 GWh). Total diesel generation decreased by 33% (1 GWh). Combined interconnector net imports from Victoria decreased by 5% (84 GWh). Rooftop PV estimated generation increased by 19% (140 GWh). South Australian operational consumption decreased from to This decline in consumption meant less generation was needed from within the state and from net interconnector imports. Table 3 also illustrates the following trends from to : An increase in coal generation after years of continued decline. This is due to the continued dry storage of Playford B power station, and the return to normal service of Northern Power Station in October An increase in wind generation, except in An increase in rooftop PV generation, concurrent with growth in rooftop PV capacity. 9 An increase in net interconnector imports, except in Section 3.1 provides further details on inter-regional changes. Note that metrics involving wind and total generation output in the 2014 SAHMIR and the 2015 SAHMIR are not directly comparable. This report includes output from Snowtown Stage 2 during , but when the 2014 SAHMIR was written, Snowtown Stage 2 was still being commissioned. Its generation levels did not meet AEMO s criteria for capacity factor analysis until 13 June 2014, and the 2014 output of the wind farm was therefore not reported in the 2014 SAHMIR. Including generation from Snowtown Stage 2 in the 2015 SAHMIR ensures alignment with the South Australian Advisory Functions reports published from September 2014 and allows for an accurate representation of total wind generation in South Australia. 10 Information relating to this wind farm s capacity factor analysis can be found in Section Rooftop PV generation is sourced from the 2015 National Electricity Forecasting Report (NEFR). Available: Viewed: 3 July AEMO NEFR. Available at: Viewed 2 July Refer to Figure 5 for details of the growth of rooftop PV capacity. 10 These reports are available on AEMO s website. Available at: Viewed: 17 July AEMO

10 Table 2 Historical energy generation for South Australian power stations (GWh) a Fuel type Scheduled generators Dry Creek Gas Hallett GT Gas Ladbroke Grove Gas Mintaro Gas Northern Coal 3,943 2,729 2,238 2,100 2,648 Osborne Gas 1,044 1,179 1,363 1,471 1,460 Pelican Point Gas 2,939 2,605 2,976 1,846 1,017 Playford B Coal Port Lincoln GT Diesel Quarantine Gas Snuggery Diesel Torrens Island A Gas Torrens Island B Gas 1,680 1,883 1,665 1,363 1,427 Semi-scheduled generators Clements Gap Hallett 1 (Brown Hill) Hallett 2 (Hallett Hill) Hallett 4 (North Brown Hill) Hallett 5 (The Bluff) Lake Bonney Lake Bonney Snowtown Snowtown Stage Waterloo Non-scheduled generators Angaston Diesel Canunda Cathedral Rocks Lake Bonney Mount Millar Starfish Hill Wattle Point Total 13,947 12,928 12,494 11,736 11,415 a. Dashes (-) in the table indicate that the generator was not registered during that financial year. AEMO

11 Technology share SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT Table 3 South Australian generation and net interconnector imports (GWh) Fuel type Gas 6,635 6,348 6,768 5,533 4,541 3,048 3,568 3,483 4,098 4,226 Coal 4,260 3,007 2,238 2,100 2,648 Diesel Interconnector net imports 566 1,136 1,405 1,673 1,589 Rooftop PV Generation share by fuel type Figure 3 shows the mix of energy generated in South Australia by fuel type from to This includes generation from: All scheduled generators. All semi-scheduled and market non-scheduled wind farms. Selected smaller market and non-market non-scheduled generators. Rooftop PV (as calculated in the 2015 NEFR). 11 Figure 3 also shows contribution from the Heywood and Murraylink interconnectors. Generation from diesel, landfill methane, and hydro generators is categorised as Other. Figure 3 South Australian energy generation by fuel type 100% 90% 3.9% 0.5% 0.4% 0.5% 0.5% 0.5% 5.1% 6.2% 0.6% 7.9% 2.2% 3.6% 9.7% 11.8% 11.4% 80% 70% 29.0% 20.8% 15.4% 14.8% 19.0% 60% 50% 20.7% 24.7% 24.0% 28.9% 30.3% 40% 30% 20% 45.3% 44.0% 46.8% 39.0% 32.7% 10% 0% Financial year Gas Coal Interconnectors Rooftop PV Other 11 The rooftop PV generation calculation methodology is published in the 2015 NEFR Methodology Information Paper. Available at: AEMO

12 In , South Australia s electricity generation by fuel type, as a percentage of total generated plus the net energy imported, was: 32.7% on gas, a reduction of 6.3 percentage points since % on wind, an increase of 1.4 percentage points since % on coal, an increase of 4.2 percentage points since % on rooftop PV, an increase of 1.1 percentage points since % on diesel, small hydro, and landfill methane (combined as Other in Figure 4), unchanged since Figure 4 shows the estimated registered generation capacity 13 by fuel type in South Australia from to , and the evolving generation mix over that time: Coal capacity has remained constant, but there has been growth in gas and diesel. There was no wind until when 38 MW was installed, growing to 1,477 MW in , an average annual growth of 44.1%. Rooftop PV capacity was negligible until , and has since grown from 15 MW to 671 MW in , an average annual growth of 89.2%. Overall capacity has increased from 3,867 MW in to 6,560 MW in , an average annual growth of 3.8%. The Heywood and Murraylink combined interconnector total nominal import capacity has been included, since it can be considered a key supply source. Net interconnector import capacity increased moderately with the addition of Murraylink from Import capacity will increase further from mid with the planned increase in Heywood interconnector s transfer capacity from 460 MW to 650 MW. Construction of the upgrade is currently in progress and more information is available on AEMO s website. 14 and rooftop PV actual generation capabilities are highly dependent on weather conditions at any given time. Data presented below Figure 4 is stacked in the same order as the fuel types on the chart itself, for easy comparison. 12 Rooftop PV generation has been included based on figures calculated in the 2015 NEFR. 13 Registered capacity values, including pro rata timing of changes during a financial year, have been estimated from a variety of publically available documents, including ESIPC Annual Planning Reviews, ElectraNet Annual Planning Reviews, and AEMO Generation Information webpages. 14 AEMO. Heywood Interconnector Update. Available: Interconnector-Update. Viewed: 2 July AEMO

13 Registered capacity (MW) Registered capacity (MW) SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT Figure 4 Registered capacity by fuel type, to ,000 6,500 6,000 7,000 5,500 6,500 5,000 6,000 4,500 5,500 5,000 4,000 4,500 3,500 4,000 3,000 3,500 2,500 3,000 2,000 2,500 1,500 2,000 1,000 1, , Gas Coal Interconnectors Diesel Landfill Methane / Landfill Gas Water Rooftop PV Rooftop PV ,129 1,203 1,203 1,217 1,473 Water Landfill Methane / Landfill Gas Diesel Interconnectors Coal Gas 2,444 2,444 2,446 2,448 2,448 2,448 2,448 2,448 2,567 2,672 2,672 2,672 2,672 2,672 2, Greenhouse gas emissions Figure 5 illustrates the level of greenhouse gas emissions in MtCO2-e produced from South Australian electricity generation, and the emissions associated with electricity imported into South Australia from the remainder of the NEM. It shows that total emissions have declined from to , but increased by 0.11 MtCO2-e (2%) from to Factors affecting the historical decline in emissions include increased wind generation, reduced coal and gas generation, and declining electricity consumption from the grid due in part to increasing rooftop PV. The emissions increase from to is due to increased coal generation following the return to year round availability of Northern Power Station. AEMO

14 Emissions (MtCO2-e) SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT Emissions calculations are comprised of: Thermal efficiencies and emission factors for each generation unit, as published in May , which are used to calculate State based emissions, using actual annual generation for South Australian power stations, and then added to Interconnector emissions, which are calculated using: Net annual interconnector imports into South Australia. NEM based emissions (based on actual annual generation from all NEM power stations excluding those in South Australia). An assumption that the emissions intensity of generation exported to South Australia is the same as the NEM-wide average excluding South Australia. 16 Figure Greenhouse gas emissions for South Australia per financial year Financial Year Emissions from South Australian generation Emissions from imports 15 All assumptions and inputs used for AEMO s planning studies, including thermal efficiencies and emission factors, are available at: Viewed 1 July NEM regional emission data is available in the 2015 NEM Historical Market Information Report. Available at: To be published in August AEMO

15 2.4 Capacity factors Figures 6 and 7 show the annual capacity factors for South Australian generation based on each power station s historical registered capacity. These capacity factors are based on the full financial year generation output. Newly-constructed generating systems that did not operate for the full financial year were included based on the proportion of the year they were operating. This gives a more representative annual capacity for each generating system, and should facilitate direct comparison with future annual capacity factors. Note that some generators may be affected by network and other constraints that could lower their capacity factors. In cases where a blank cell is shown for a generator s capacity factor for a given period, it means no factor has been calculated due to the generator not being considered available for analysis at all during that period. The reason for not being available for analysis would be either a generator not being commissioned at all during this period, or a wind farm first reaching 90% of registered capacity during this period, but not for long enough to calculate an indicative capacity factor. Generating systems that respond to peak demand generally have lower capacity factors, as they operate for short time periods and are idle most of the year. Base-load generating systems, typically have higher capacity factors as they tend to power continuously unless shut down for maintenance. Changes of note between the and financial years are: Similar or lower capacity factors for most gas-powered generators. Northern Power Station s capacity factor reversed the recent historical downward trend by increasing from 45.2% to 57% from to , due to its changed operating regime. 17 Pelican Point power station s capacity factor continued to decline, reducing from 44.1% in to 24.3% in This reduction was in part due to the mothballing of 50% of the station s capacity from April Capacity factors for all wind farms are lower for than for This correlates with less wind measured at the wind farm locations. 19 Figures 8 to 11 show the capacity factors for both summer (defined as 1 November to 31 March) and winter (defined as 1 June to 31 August). They highlight the different seasonal operating patterns for specific generators and illustrate that wind farms and gas-powered generators on average have higher capacity factors in the winter, while coal-powered and diesel-powered generators on average have higher capacity factors in the summer. Note that in Figure 9, Osborne Power Station s capacity factor was calculated as greater than 100% for winter This is due to calculations being made on registered capacity (180 MW), which in this case is substantially lower than both the maximum capacity (204 MW) and the actual generation output levels achieved during this time period. Snowtown Stage 2 capacity factors are included for the first time in this year s report. Note that, in Figures 7, 10 and 11, capacity factors are not presented for this wind farm for summer and the financial year. For the winter 2014 analysis, the time analysed is from 13 June to 31 August 2014, and the financial year analysis covers the full period. This is because, as discussed in Section 2.1, the wind farm only satisfied capacity factor analysis criteria from 13 June Alinta Energy advised that Northern Power Station returned back to normal service in October This followed periods of withdrawal from April to September in 2013 and Source: AEMO Generation Information Pages. Available: Information/Generation-Information. Viewed 2 July Source: AEMO Generation Information Pages. Available: Viewed 2 July Based on AEMO s analysis of average wind speed telemetry from wind farm sites across South Australia. AEMO

16 AEMO Capacity factor (%) Figure 6 Financial year capacity factors for scheduled generators 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Dry Creek Hallett GT Ladbroke Grove Mintaro Northern Osborne Pelican Point Playford B Port Lincoln GT Quarantine Snuggery Torrens Island A % 1.4% 19.6% 0.3% 84.9% 66.2% 70.2% 15.1% 0.3% 6.9% 0.1% 16.0% 24.0% % 0.5% 11.5% 0.7% 58.6% 74.6% 62.1% 13.2% 0.1% 3.3% 0.1% 12.3% 26.8% % 3.7% 13.2% 1.6% 48.2% 86.5% 71.1% 0.0% 0.2% 7.7% 0.0% 10.5% 23.8% % 2.1% 33.1% 1.0% 45.2% 93.3% 44.1% 0.0% 0.1% 12.3% 0.0% 8.0% 19.4% % 1.4% 26.5% 0.9% 57.0% 92.6% 24.3% 0.0% 0.1% 11.1% 0.1% 4.7% 20.4% Torrens Island B

17 AEMO Capacity factor (%) Figure 7 Financial year capacity factors for non-scheduled and semi-scheduled wind farms 100% 90% Non-scheduled wind farms Semi-scheduled wind farms 80% 70% 60% 50% 40% 30% 20% 10% 0% Canunda Cathedral Rocks Lake Bonney Mount Millar Starfish Hill Wattle Point Clements Gap Hallett 1 (Brown Hill) Hallett 2 (Hallet Hill) Hallett 4 (North Brown Hill) Hallett 5 (The Bluff) Lake Bonney 2 Lake Bonney 3 Snowtown Snowtown Stage % 30.6% 26.0% 29.7% 24.4% 32.8% 33.8% 38.8% 39.2% 27.6% 26.0% 24.9% 40.0% 27.3% % 31.8% 28.5% 30.6% 28.1% 34.0% 35.1% 40.0% 40.8% 39.5% 28.9% 27.6% 25.4% 43.3% 32.0% % 30.2% 27.0% 30.2% 22.4% 31.1% 33.6% 40.1% 41.1% 36.8% 33.7% 27.5% 28.0% 43.3% 32.2% % 34.0% 29.2% 33.2% 31.1% 37.0% 35.3% 42.3% 41.1% 40.9% 36.4% 30.2% 29.9% 45.1% 34.9% % 29.4% 27.1% 30.5% 28.2% 33.2% 33.7% 37.3% 37.4% 36.3% 29.5% 28.7% 27.6% 38.6% 34.8% 30.2% Waterloo

18 AEMO Capacity factor (%) Figure 8 Summer capacity factors for scheduled generators 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Dry Creek Hallett GT Ladbroke Grove Mintaro Northern Osborne Pelican Point Playford B Port Lincoln GT Quarantine Snuggery Torrens Island A % 2.7% 19.1% 0.4% 89.7% 61.1% 69.7% 22.6% 0.5% 6.2% 0.1% 15.0% 23.1% % 0.4% 8.7% 0.5% 60.0% 72.5% 65.6% 17.6% 0.1% 1.9% 0.0% 8.0% 26.7% % 0.8% 5.6% 0.7% 82.7% 84.0% 73.8% 0.0% 0.2% 6.8% 0.1% 7.3% 21.2% % 3.1% 25.3% 1.0% 62.4% 98.4% 47.3% 0.0% 0.3% 9.4% 0.0% 7.3% 20.1% % 0.8% 17.2% 0.5% 59.7% 90.4% 33.4% 0.0% 0.0% 14.3% 0.1% 3.4% 18.8% Torrens Island B

19 AEMO Capacity factor (%) Figure 9 Winter capacity factors for scheduled generators 100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% Dry Creek Hallett GT Ladbroke Grove Mintaro Northern Osborne Pelican Point Playford B Port Lincoln GT Quarantine Snuggery Torrens Island A % 0.6% 25.1% 0.1% 77.4% 79.2% 79.3% 38.5% 0.1% 11.4% 0.0% 21.0% 23.9% % 0.3% 17.9% 0.0% 48.1% 82.2% 66.2% 0.0% 0.0% 1.9% 0.0% 23.1% 26.0% % 0.3% 21.0% 0.3% 35.3% 91.1% 78.3% 0.0% 0.3% 5.2% 0.0% 13.1% 36.3% % 6.6% 20.7% 2.0% 19.8% 80.3% 49.5% 0.0% 0.1% 18.3% 0.0% 24.3% 22.3% % 2.3% 39.9% 2.1% 45.3% 101.0% 44.0% 0.0% 0.1% 6.9% 0.0% 1.6% 25.7% Torrens Island B

20 AEMO Capacity factor (%) Figure 10 Summer capacity factors for non-scheduled and semi-scheduled wind farms 55% 50% Non-scheduled wind farms Semi-scheduled wind farms 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% Canunda Cathedral Rocks Lake Bonney Mount Millar Starfish Hill Wattle Point Clements Gap Hallett 1 (Brown Hill) Hallett 2 (Hallet Hill) Hallett 4 (North Brown Hill) Hallett 5 (The Bluff) Lake Bonney 2 Lake Bonney 3 Snowtown Snowtown Stage % 30.8% 22.3% 28.8% 27.9% 36.5% 36.2% 36.3% 36.8% 35.3% 23.2% 22.6% 42.4% 32.1% % 30.2% 26.5% 30.4% 32.0% 38.4% 40.0% 37.0% 37.2% 39.7% 30.8% 27.1% 26.1% 46.8% 30.7% % 31.1% 25.4% 30.7% 17.9% 35.8% 36.3% 37.6% 37.8% 36.3% 30.1% 26.4% 27.2% 44.9% 29.1% % 32.1% 22.7% 32.1% 31.4% 39.2% 38.3% 34.9% 33.5% 36.4% 27.6% 24.5% 24.6% 46.3% 28.7% % 29.7% 24.9% 29.9% 28.7% 37.7% 36.9% 32.7% 32.9% 34.3% 25.0% 27.0% 26.9% 39.8% 35.2% 26.3% Waterloo

21 AEMO Capacity factor (%) Figure 11 Winter capacity factors for non-scheduled and semi-scheduled wind farms 55% 50% Non-scheduled wind farms Semi-scheduled wind farms 45% 40% 35% 30% 25% 20% 15% 10% 5% 0% Canunda Cathedral Rocks Lake Bonney Mount Millar Starfish Hill Wattle Point Clements Gap Hallett 1 (Brown Hill) Hallett 2 (Hallet Hill) Hallett 4 (North Brown Hill) Hallett 5 (The Bluff) Lake Bonney 2 Lake Bonney 3 Snowtown Snowtown Stage % 30.2% 29.8% 30.5% 21.5% 30.8% 31.3% 41.6% 42.6% 1.1% 26.4% 20.1% 38.7% 2.2% % 35.2% 35.0% 33.7% 24.6% 32.4% 32.6% 45.4% 46.0% 42.3% 6.5% 32.1% 30.6% 40.6% 35.1% % 33.2% 33.5% 32.6% 30.0% 34.4% 32.3% 49.8% 53.0% 38.7% 43.7% 32.3% 33.2% 44.8% 41.1% % 36.7% 35.9% 37.2% 30.0% 37.2% 32.3% 48.4% 48.0% 42.3% 42.8% 36.8% 38.8% 43.2% 36.4% % 31.4% 28.6% 35.9% 30.1% 31.9% 32.3% 46.1% 45.4% 43.9% 40.6% 29.7% 27.3% 41.7% 41.4% 40.4% Waterloo

22 3. INTER-REGIONAL SUPPLY 3.1 Annual interconnector flows Tables 4, 5, and 6 show the annual energy imported and exported since , and the annual average power flows for the Heywood and Murraylink interconnectors. Import is defined as the energy flow from Victoria to South Australia, and export as energy flow from South Australia to Victoria. In combined interconnector total imports (Table 6) increased by 4% compared to , total exports increased by 49%, and combined net interconnector imports decreased by 5%. This indicates a greater reliance on interconnectors. Table 4 Historical Heywood Interconnector power flow Financial year Total imports (GWh) Total exports (GWh) Import average (MW) Export average (MW) , , , , , , , , Table 5 Historical Murraylink Interconnector power flow Financial year Total imports (GWh) Total exports (GWh) Import average (MW) Export average (MW) AEMO

23 Table 6 Historical combined interconnector power flow Financial year Total imports (GWh) Total exports (GWh) Net imports (GWh) , , , , , , , , , , , , ,589 Figure 12 shows total imports and exports into South Australia from to Energy imported into South Australia from Victoria during the year is plotted in the orange column bars above the 0 GWh line (x-axis), and energy exported from South Australia to Victoria is shown below the line. Combined interconnector flows from to show 20 a clear tendency for high levels of imports and very low levels of exports, compared to more recent history. From onwards, a combination of factors led to greater exports, including: Drier or drought conditions affecting interstate hydro generation supplies. An increase in the number of wind farm generators in South Australia. From to , a trend is apparent in steadily increasing total imports. 20 As published in the 2013 SAHMIR, available from AEMO on request. AEMO

24 GWh SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT Figure 12 3,000 Total interconnector imports and exports 2,500 2,000 1,500 1, , Financial Year Imports (flows from Victoria to South Australia) Exports (flows from South Australia to Victoria) 3.2 Daily average interconnector flow patterns Figure 13 shows annual flow patterns for combined interconnector imports (from Victoria to South Australia), with times expressed in NEM time (also known as market time). On average, combined interconnector imports exhibit a peak from around 18:00 hrs to 22:00 hrs, and a trough from around 02:00 hrs to 07:00 hrs. These correlate with the peaks and troughs in South Australian daily operational consumption. The sudden dip then subsequent spike in imports occurring around 23:30 hrs to 00:00 hrs is caused by automated off-peak hot water systems switching on in Victoria, followed by South Australia. Figure 14 provides a breakdown of the interconnector flow patterns for It shows that, on average, Heywood tends to import electricity from Victoria, whereas Murraylink flow is dominated by exports to Victoria. Figures 15 and 16 outline interconnector flow averages for each 5-minute dispatch interval of each day over the past three years for business days in summer and winter. Note that the winter 2015 curve only includes data for the month of June Daily average imports are generally higher during winter. AEMO

25 Interconnector flow (MW) Interconnector flow (MW) SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT Figure Combined interconnector daily 5-min average flow Time of day (NEM) Time of day (NEM) time time Summer Summer Summer Figure Heywood, Murraylink and combined interconnector daily 5-min average flow Time Time of of day day (NEM) (NEM) time time Average Summer of Heywood Summer - Average of Murraylink Summer - Average of Combined AEMO

26 Interconnector flow (MW) Interconnector flow (MW) SOUTH AUSTRALIAN HISTORICAL MARKET INFORMATION REPORT Figure 15 Combined interconnector summer daily 5-min average flow (business days only) Time of day (NEM) time Summer Summer Summer Figure Combined interconnector winter daily 5-min average flow (business days only) Time Time of of day day (NEM) (NEM) time time Winter 2013 Summer Winter 2014 Summer Winter Winter (to Summer (to June June 2015) ) AEMO

27 3.3 Flow duration curves Flow duration curves are a graphical representation of the frequency of power being transferred via interconnectors. Lines above the x-axis indicate imports from Victoria into South Australia. The area between the curves and the x-axis represents the amount of energy being transferred between these regions. Flow duration curves indicate interconnector utilisation. Heywood and Murraylink have a nominal import capacity of 460 MW and 220 MW respectively, and a combined nominal import capacity of 680 MW. Under normal system operating conditions, combined export capability is 580 MW, due to electricity network stability constraints. 21 Under certain conditions the interconnectors can exceed the maximum nominal import capacity for brief periods; this typically depends on the short-term equipment ratings. Figures 17 and 18 show flow duration curves for the Heywood and Murraylink interconnectors over the past three years. The stepped flow duration curves for Murraylink reflect its banded transfer constraints. The figures also illustrate the utilisation of the Heywood and Murraylink interconnector import capacity. Table 7 below quantifies the percentage time in each of the past three financial years, where each interconnector was being utilised at or above 100% of its nominal import capacity. At times, interconnectors may be utilised below nominal import capacity due to other network constraints. Information regarding how constraints affect the actual capability of these interconnectors is available in AEMO s NEM Constraint Report. 22 Table 7 Percentage of financial year having full utilisation of nominal import capacity Interconnector Heywood 8.5% 6.6% 9.3% Murraylink 0.6% 0.2% 0.1% Figure 19 shows the combined Heywood and Murraylink electricity flows, and further demonstrates that South Australia increased its net import from Victoria compared to previous years, but also comparatively increased its net export. This is also reflected in Figure 12. Figure 20 shows interconnector utilisation as a percentage of total transfer capacity. This indicates that imports over the Heywood Interconnector are closer to its total capacity compared to Murraylink, which conversely shows better utilisation of its export capacity. The different characteristics observed between Heywood and Murraylink import and export trends are a product of the NEM s optimised operation, which includes the following pertinent factors: Network constraints. Location of generation, particularly South Australian wind farms. Transmission network electrical and geographical characteristics. Location of major load centres. Generator bids. 21 ElectraNet. South Australian Transmission Annual Planning Report May Available at: Papers/2015-Transmission-Annual-Planning-Report.pdf. Viewed: 2 July AEMO. NEM Constraint Report 2014.Sections 5.5 and 5.6. Available: Operations/Dispatch/~/media/Files/Other/Dispatch%202014/NEM%20Constraint%20Report% ashx. Viewed: 27 July AEMO

28 Figure 17 Heywood Interconnector flow duration curves Figure 18 Murraylink Interconnector flow duration curves AEMO

29 Figure 19 Combined interconnector flow duration curves Figure 20 Interconnector flow as a percentage of interconnector capacity AEMO

30 4. LINKS TO SUPPORTING INFORMATION Information source AEMO Generator Information page AEMO South Australian Advisory Functions NEM Historical Market Information Report AEMO National Electricity Forecasting Report AEMO Current Registration and Exemption lists Website address Information Market-Information-Report (to be published in August 2015) Forecasting-Report AEMO

31 MEASURES AND ABBREVIATIONS Units of measure Abbreviation GWh MW MtCO2-e Unit of measure Gigawatt-hour Megawatts Megatonnes of carbon dioxide equivalent Abbreviations Abbreviation AEMO ESIPC MSATS NEFR NEM PV Expanded name Australian Energy Market Operator Electricity Supply Industry Planning Council Market Settlements and Transfer Solutions National Electricity Forecasting Report National Electricity Market Photovoltaic AEMO