There's been a lot of talk about power price rises here in Australia. So what's causing it?
Short answer: Old coal-fired power stations that keep breaking down.
In detailed terms, here's a chart from finance reporter Elysse Morgan, showing the power output of AGL's coal-fired power stations over the last month or so.
The purple line at the top is what they would normally be producing - if the stations were all functional, and not having "unplanned outages". The difference is around a million homes.
Of course the electricity grid normally makes up for this shortfall by having gas-fired power stations operate as a backup. But this is quite expensive. Perhaps because the shortage is so large. Perhaps because the gas price (globally) is so high at the moment. Perhaps a combination of the two.
The result is that energy costs more, as shown in this graph of energy prices in the states of Queensland (QLD) and Victoria (VIC).
Elysse Morgan points out that Western Australia (WA), as a gas-exporting state, requires companies to provide gas for WA first (at a fixed price).
As a sidenote she also points out that renewables like wind and solar also have a stable and low per-unit cost - as the power source is free.
Ah, if only we'd built more of that earlier.
