Modo puts Western Australia's grid-battery index at $184,100 a megawatt for October - capacity credits are 91% of that revenue, the 2028-29 price on AEMO's page is a different year, and a factory invoice is not in the index
On 2 November 2026 Modo Energy put its Wholesale Electricity Market battery index at $184.1k per MW per year for October, up 3.7 times from September. Reserve Capacity payments accounted for 91% of that revenue. The index is seven grid batteries, 1,485 MW, after Alinta's Wagerup battery joined. No megawatt-hours and no workplace site are printed. AEMO's page prints $459,191.55 per MW per year for the 2028-29 capacity year. That is a later year.
A dollar figure per megawatt per year, on a grid-battery index, is not the saving on a factory bill. The index is a set of batteries that sell into Western Australia's wholesale market. A workshop meter is a different piece of paper.
On 2 November 2026 Modo Energy published its October read of battery revenue in the Wholesale Electricity Market, the WEM. The index, which the page calls ME BESS AUS WEM, rose to $184.1k per MW per year. Written in full, $184.1k is $184,100. The page says that is up 3.7 times from September. It names Reserve Capacity payments as the reason the index jumped. Four existing batteries began receiving those payments as the 2026-27 capacity year started. Alinta Energy's Wagerup battery began operating and joined the index in October. The page says the index fleet is now 1,485 MW, and that all seven batteries in it receive Reserve Capacity payments. Those payments accounted for 91% of October revenue on the index.
The trading slice, as the page describes it. Lower evening prices narrowed the two-hour spread for a fourth month. A two-hour spread is the gap between a dear pair of hours and a cheap pair. The page says higher rooftop solar output also lowered daytime prices, and that the reduction in evening value outweighed the benefit of cheaper charging. Inside that smaller gap, lower charging cost lifted merchant revenue. The page's word for three of Synergy's four batteries is merchant-positive: trading, apart from the capacity payment, came out ahead. The opening of the page says three of Synergy's batteries. The summary says three of its four. The dollar width of the two-hour spread is not printed. A cents figure for a workplace is not printed.
What the page leaves off. No megawatt-hours, so a reader cannot turn 1,485 MW into hours of storage. No solar plant paired with these batteries. No factory, farm, warehouse or shop. Wagerup's own megawatts are not split out of the 1,485. The 91% is a share of index revenue. The page does not print the dollars per capacity credit that produced the share. A capacity credit is a right to a payment for capacity the market operator has assigned. The page does not print the assignment for any one battery.
A different year, on the market operator's own page. AEMO's reserve capacity price page, in the section for the 2026 reserve capacity cycle and the 2028-29 capacity year, prints a peak reserve capacity price of $459,191.55 per MW per year. That price is for a capacity year that starts later. Modo's $184,100 is an October 2026 index result, and the page ties the jump to the 2026-27 capacity year, the one that has started. The two pages do not say the figures are the same payment. $459,191.55 is not 91% of anything on the Modo page. Neither figure is a line on a business invoice.
The east-coast note already on this desk is a third sheet. The September-quarter note is about grid batteries setting the spot price in the National Electricity Market. This note is a capacity payment in Western Australia, on an analyst's index. A fixed retail invoice for a workshop is neither sheet. Rooftop solar shows up here only as a reason daytime wholesale prices were lower. That is not a discount on a factory's bill.
Analogy: $184,100 is the index rent for one megawatt for a year, across seven grid batteries. On the page's share, 91 cents in the dollar is the capacity payment, a fee for being available. The other slice is not itemised as a saving at a workplace. A screenshot of the index is not a contract.
Good: A dated index, a named market, a per-megawatt figure, a 91% share with a named payment, a fleet count of seven and 1,485 MW, and a second official page that prints a different year's price in full cents.
Bad: September's dollar is not beside the 3.7 times in the lines the page leads with. The two-hour spread has no dollar width. Wagerup's megawatts are inside the 1,485, not beside it. No megawatt-hours. The 91% is an index share, not a tariff. $459,191.55 is a later capacity year. Three of Synergy's batteries and three of its four are both on the page.
Ugly: Putting $184,100 a megawatt on a factory quote. Treating 91% as a discount off a battery invoice. Pasting the 2028-29 reserve capacity price onto October's index. Reading 1,485 MW as solar. Reading rooftop solar's effect on the daytime price as a credit on a workplace bill.
Soft next step: keep $184,100 on the grid-battery index, and leave it off a factory quote.
Source: Modo Energy, Marcus Freese, published 2 Nov 2026 - WEM battery revenues for October 2026. Primary for the ME BESS AUS WEM index at $184.1k per MW per year in October, the statement that this is up 3.7 times from September, Reserve Capacity payments as the driver, four existing batteries beginning those payments as the 2026-27 capacity year started, Alinta Energy's Wagerup battery beginning operation and joining the index, the fleet at seven batteries and 1,485 MW, all seven receiving Reserve Capacity payments, those payments accounting for 91% of October revenue, two-hour spreads narrowing for a fourth month, higher rooftop solar output and lower daytime prices, a smaller charge-and-discharge opportunity, cheaper charging lifting merchant revenue, and three of Synergy's batteries, with the summary saying three of its four, described as merchant-positive. $184.1k written as $184,100 is our expansion of the page's own abbreviation. The page does not print megawatt-hours, a dollar width for the spread, Wagerup's megawatts on their own, or a workplace. The page marks publication at 2026-11-02T03:30:27+00:00. AEMO - Reserve Capacity Price, WEM. Primary for the peak reserve capacity price of $459,191.55 per MW per year in the section for the 2026 reserve capacity cycle, the 2028-29 capacity year. That section is not Modo's October index, and it is not a 2026-27 payment.