Each month, Watt Utilities publishes this Commercial Energy Market Report to keep our clients informed about wholesale electricity price movements across Australia’s east coast. We cover what happened in the spot market, why prices moved, and what it means for businesses managing energy costs. A new edition is released around the 20th of the following month.
Australia’s electricity grid operates through the National Electricity Market (NEM), which connects Queensland, New South Wales, Victoria and South Australia via a shared transmission network. Wholesale spot prices are set every five minutes through a competitive bidding process managed by AEMO (the Australian Energy Market Operator), the independent body responsible for operating the NEM and ensuring reliable electricity supply. The prices in this report reflect the wholesale spot market and are distinct from the retail rates businesses pay on their energy bills, though sustained movements in the spot market generally feed into retail contract pricing over time. This report covers the mainland NEM only (Queensland, New South Wales, Victoria and South Australia).
April 2025 saw spot prices rise across all mainland NEM states compared to March 2025, driven by coal generator outages and interconnector constraints. New South Wales recorded the highest average at $104.07/MWh with 25 high-price intervals, while Queensland averaged $98.50/MWh with 24. South Australia recorded two high-price intervals as lower wind generation increased reliance on alternative supply sources. Victoria averaged the lowest at $74.76/MWh with zero high-price events, despite a high count of zero or negative pricing intervals. FY2026 forward contracts saw upward pressure early in the month before stabilising, closing the month broadly unchanged from March.
Source: Shell Energy / AEMO
| State | Average Spot Price | Max 5 Min Spot Price | 5 Min Intervals at $1,000+ | 5 Min Intervals at $0 or Below |
|---|---|---|---|---|
| QLD | $98.50 | $15,335.23 | 24 | 1,459 |
| NSW | $104.07 | $17,498.96 | 25 | 1,028 |
| VIC | $74.76 | $983.96 | 0 | 1,529 |
| SA | $88.82 | $1,000.00 | 2 | 1,631 |
Source: NEM Spot Market, AEMO (via Shell Energy Market Summary Report, April 2025)
Source: NEM Spot Market, AEMO. Chart Credit: Shell Energy. Historical data prior to Sep 2025 sourced from Shell Energy 3-year charts.
FY2026 forward contracts saw upward pressure in early April as spot market volatility, particularly in cap products for QLD and NSW, prompted initial hedging activity. By month-end, however, prices had stabilised with all four states ending broadly unchanged from March. QLD’s FY26 contract closed at $107.77/MWh, NSW at $122.35/MWh, SA at $95.16/MWh and VIC at $80.90/MWh. For businesses with renewals in FY2026, April’s forward market stability meant the spot volatility did not translate into a materially different contracting environment by month-end. With winter approaching and coal reliability concerns building (as demonstrated by the Callide incident), forward prices in subsequent months reflected increasing winter risk premium, making April a relatively contained window to have engaged the contract market.
Spot price averaged $104.07/MWh in April, up 15.7% from March’s $89.96/MWh. The 25 high-price intervals were concentrated around April 9, when the daily average reached $311.08/MWh. The peak five-minute interval of $17,498.96/MWh is an AEMO-published market price from the competitive bidding process during acute supply tightness.
Planned and unplanned coal generator outages combined with constraints on the VIC-NSW interconnector created the most volatile conditions on the mainland NEM in April. The restriction on interstate power flows amplified local pricing pressures during the April 9 supply event. NSW recorded 1,028 zero or negative pricing intervals as renewable output provided relief across lower-demand periods.
Source: AEMO (via WEB_AVERAGE_PRICE_DAY_202504)
Spot price averaged $98.50/MWh in April, up 24.7% from March’s $79.01/MWh. The 24 high-price intervals above $1,000/MWh included a maximum of $15,335.23/MWh, representing legitimate AEMO market prices from the competitive bidding process during supply-constrained periods.
Coal generator outages (including the April 4 Callide Power Station explosion) and interconnector constraints limited power flows, contributing to elevated spot prices and 24 high-price intervals. Strong solar penetration provided 1,459 zero or negative pricing intervals during daylight hours, moderating the daily average impact of the high-price events.
Source: AEMO (via WEB_AVERAGE_PRICE_DAY_202504)
Spot price averaged $88.82/MWh in April, up 43.8% from March’s $61.75/MWh. Despite recording only two high-price intervals, the higher average reflects reduced wind generation across the month increasing reliance on gas-fired and other alternative generation sources during lower-wind periods.
Relatively low wind generation levels contributed to higher spot outcomes, with two intervals reaching exactly $1,000.00/MWh during brief supply shortfalls. SA recorded 1,631 zero or negative pricing intervals, the highest count across the mainland NEM for April, as solar generation created extended oversupply periods during daylight hours across the month.
Source: AEMO (via WEB_AVERAGE_PRICE_DAY_202504)
Spot price averaged $74.76/MWh in April, up 21.0% from March’s $61.79/MWh and the lowest mainland average for the month. Zero high-price intervals above $1,000/MWh were recorded, though intra-month volatility was notable with the April 9 daily average reaching $144.14/MWh.
Constraints on the VIC-NSW interconnector and strong renewable output created 1,529 intervals at or below zero pricing. The interconnector limitations meant Victoria could not efficiently export its surplus generation northward during oversupply periods, contributing to both the high zero-price interval count and the state’s lower average relative to NSW and QLD.
Source: AEMO (via WEB_AVERAGE_PRICE_DAY_202504)
Source: Shell Energy Market Summary Report, April 2025 (AEMO fuel mix data)
Coal held 63% of NEM output over the 90-day period to April (black coal 46%, brown coal 17%), with wind at 15%, solar at 10% and hydro at 7%. Gas contributed 5%. The 63% coal share reflects the late-summer and autumn period where solar declines from its peak but wind has not yet reached winter levels, leaving coal as the dominant balancing source and making unplanned outages particularly impactful on spot prices.
Watt Utilities welcomed two new energy managers to the team in April. Mahee Moturu joins as our Victorian Energy Manager, bringing extensive commercial and industrial (C&I) sector experience to our growing Victorian client base. Dean Van Der Heever joins our Robina office, where he will look after SME clients across Queensland.
Both additions strengthen our capacity to deliver personalised service across the SME and C&I segments. Our Watts Mine platform, which has incorporated AI-driven analysis for over two years, supports both Mahee and Dean’s client work with real-time market intelligence and contract analytics, allowing the team to act quickly when market conditions shift.
CS Energy came under pressure to restart Queensland’s Callide Power Station by 30 May 2025 following an explosion at the facility on 4 April that disrupted one of its generator units. The incident added to existing market concerns about the reliability of ageing coal generation infrastructure and its effect on energy costs, particularly as winter demand approached and supply margins tightened across the NEM.
Source: CS Energy / AEMO, April 2025
BOC Australia signed a 10-year agreement with ZEN Energy in April 2025 to source over 45% of its electricity from solar power across Queensland, New South Wales and Victoria. The deal represents a significant corporate renewable energy commitment from one of Australia’s major industrial gas and energy businesses, with the partnership expected to reduce BOC’s carbon emissions across its operations.
Source: ZEN Energy / BOC Australia, April 2025
Our team works with SME, C&I and Strata clients across Queensland, New South Wales and Victoria. Get in touch for a no-obligation portfolio review.
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