Huntly vs Other Thermal Stations
Quote:
Originally Posted by
Paper Tiger
Snoopy wrote".But if Huntly has to close, and of all the power stations in NZ it is the most likely candidate for closure IMO..."
Why?
A fair question PT. I need to explain some more background here to give a full answer.
'Huntly' is probably better described as 'a collection of power stations operating on one site' rather than 'a power station'. Originally Huntly consisted of four what is termed "Rankine Units" rated at 250MW each and can operate on natural gas or coal. These were commissioned over the 1982 to 1985 period. As of today only two of these original units are operational. Number four has been fully decommissioned. Number three was put into storage at the end of 2013.
In 2007 what is termed 'Unit 5' a 400MW unit was commissioned at Huntly. This is a combined gas cycle gas turbine that only runs on natural gas. There is also a much smaller 50.8MW 'Unit 6' commissioned in 2004 that runs on gas and diesel.
There are two other gas powered stations well sited to serve the Auckland market. These are "Otahuhu B", commissioned in 1999 and owned by Contact Energy, with a total generating capacity of 380MW and "Southdown", commissioned in 1996 and owned by Mighty River Power with a total generatinng capacity of 175MW.
When I said "if Huntly had to close", I more correctly should have said "If part of Huntly had to close", because as I said before Huntly is really 2 1/2 power stations on the one site. The bit I was referring to that might have to close are the two older Rankine units. I believe this is likely because one of them has already closed and another is in storage. Also they are by far the oldest of the thermal power stations remaining in the upper North Island. So simply from a wear and tear perspective it makes sense to me that these two would be most likely to shut down first because:
1/ They have done the most work.
2/ They have the oldest technology, are not as efficient as 'Unit 5' and probably not as efficient as "Otahuhu B" or "Southdown" either.
Furthermore on the demand side, while Genesis has 26.8% of the NZ electricity market (p16 investment statement) they only have 19% of the Auckland market. Their relatively low market share in the largest market (Auckland) leads me to belive that they would still be able to supply all of their customers (they claim unit 5 alone and the hydro can do this already) and don't really need an old inefficent power generator (the rankine units) as backup when the overall market is well supplied with power.
SNOOPY