The graphs below were generated to look at in more detail the operation of the Eraring Coal Units in the NSW Region following the publishing of an article on RenewEconomy titled Energy oligopoly using market power to profit under cover of rooftop solar (Wed 12 Feb 2020) by Bruce Mountain and Dr Steven Percy.
As noted in the Graph below, the Eraring Station Output reduced in 2019 Q4 compared to 2018 Q3 and NSW Rooftop PV increased. The point of contention was that NSW Gas had increased 2019 Q4 to 2018 Q4. Gas being a more expensive fuel than Black Coal, the concern was that Eraring was withholding capacity.
The Graph below, also shows the NSW Price (Dispatch - 5min - Non-Intervention). There is a noticeable decrease in the price during the daylight hours and an increase in the non-solar producing hours. Overall the average NSW Price dropped 11.06 $/MWh, from 86.62 $/MWh in 2018 Q4 to 75.56 $/MWh for 2019 Q4.
The graphs below show the Eraring Unit Availability (right axis - solid line) and Output (right axis - dotted line) as Daily Profile (Mean) for the 2019 Q4 (left graph) and 2018 Q4 (right graph).