ACEnergy sells 250MW Yanco BESS to BW ESS ahead of 2028 commercial start
The deal adds to a growing secondary market for pre-operational battery assets as Australia's NEM project pipeline reaches record volumes.
ACEnergy has sold its 250-megawatt Yanco battery energy storage system to BW ESS, with commercial operations targeted for 2028. The transaction is part of a growing secondary market in Australian large-scale storage, where developers are transferring pre-operational assets as a buildout straining the connection queue reaches record volumes.
Australia added 9.1GW of new generation and storage to the National Electricity Market in financial year 2026, more than double the FY25 total, according to AEMO. The overall project pipeline expanded 42% year-on-year to 75.4GW, up from 53GW in FY25, driven by record wind applications and continued growth in battery storage.6
Wind led the application surge: AEMO received 12 wind project applications totalling 5.2GW in FY26, the highest annual volume on record. But applications and completions are pulling apart. AEMO approved 14.2GW of project applications and 7.4GW of registrations during FY26, while only 6.4GW progressed through the developer-led implementation stage, out of 14.4GW that entered it.6
That gap between entry and completion defines the secondary market. Developers holding grid connection rights but facing capital constraints or shifting priorities become sellers. BW ESS acquires Yanco with approximately two years to navigate AEMO's registration and connection requirements before the 2028 commercial target.
The deal is not the only transaction of its kind in the current cycle. In May (2026-05-20), Enervest acquired the 300-megawatt Northern Border Battery from a Sydney-based developer, with construction expected to begin in early 2028, the same targeted commercial year as Yanco.1 On June 9 (2026-06-09), Ark Energy received approval from AEMO and Transgrid to connect its 435-megawatt Richmond Valley solar-plus-storage project in northern New South Wales, demonstrating that the NEM connection pathway can be cleared for projects of comparable scale within the same timeframe.5,4
Demand growth supports the investment thesis alongside the grid capacity need. Data centre capacity in Australia is projected to reach 6.5 gigawatts, and electric vehicle sales reached 157,000 units in FY26, a 38% year-on-year increase, according to market analysis covering the 2026-2034 period. Both are vectors for new peak demand concentrated in evening ramp periods, when battery storage is best positioned to respond.2
AEMO issued a succession of market notices starting Sunday (2026-06-07) forecasting a Lack of Reserve Level 2 condition for South Australia on Wednesday (2026-06-10). By the final update on Monday (2026-06-08), the minimum capacity reserve available in the afternoon window was 384 megawatts against a requirement of 571MW. South Australia NEM spot power traded at A$163.42 per megawatt-hour as of 2026-08-14 08:20 UTC. Storage dispatching into those reserve events generates the merchant revenue that justifies development at current costs.3
Wallumbilla gas hub spot traded at A$10.55 per gigajoule as of 2026-08-14 08:20 UTC, the counterfactual against which storage revenue is measured. Battery dispatch holds a clear economic edge when reserve calls are concentrated in short, high-priced windows — precisely the conditions AEMO's successive market notices described.
In the June quarter alone, 14 NEM projects with a combined 3.9GW reached full output, and eight totalling 1.5GW achieved registration, showing that projects can clear the final stages at pace.6 BW ESS will need similar execution: with 75.4GW in the pipeline, network service providers face simultaneous connection requests from competing developers, and AEMO's processing bandwidth is finite.6
Projects that miss their commercial start date face stranded development costs in a market where simultaneous entry of significant new capacity would compress merchant spreads. The Yanco 2028 target is achievable, but the connection queue is contested by dozens of comparable projects, leaving BW ESS little room for delay.6