Negative prices leave many bemused, as Global-Roam helps to explain

Over on WattClarity, Paul first noted a growing trend of Queensland region prices dropping below $0/MWh at the end of August, as that trend continued into September more discussion on the topic was published on the site with Allan O’Neil analysing who was responsible for the market phenomenon and how it was influencing bidding behavior.


Several industry journalists attempted to explain the cause and effect of the negative prices, with Paul providing quotes to the national media discussion:

In a separate analysis, Global-ROAM’s Paul McArdle found increases in capacity bid into the NEM at negative electricity prices and in capacity bid in at over $300/MWh, reducing the incidence of more normal pricing.

Electricity market analyst Global-ROAM pointed to a trading price for the half-hour to 10am of -$413.65/MWh, followed by one -$731.11/MWh. In theory power generators operating then were paying hundreds of dollars for every megawatt-hour they produced, depending on their contracts and hedging.