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Tamar Valley CCGT reached full output at 11:55am today following yesterday's startup.
Also some of the OCGT's in Tas were run today. That was a purely commercial decision, not required for any technical reason, in response to interstate market prices. Had they not been run then someone else in another state would have supplied that power at whatever price but in short Hydro Tas was offering a lower price than others who had idle or underutilised plant at that time. A commercial decision in all cases. Likewise everyone else with plant running would have been offering supply at lower price than those who had plant sitting idle since price is the basis of dispatch subject to any technical constraints (eg maximum flow on transmission lines) being met.
Today's hot weather in NSW pushed demand there to high levels and that was supplied from Qld and Vic as well as from sources within NSW. With demand fairly low in Vic, Tas and SA the transmission lines Vic - NSW were at their limit transferring power north.
A considerable amount of oil-fired generation, a few hundred MW, was run in Qld today in order to supply power into NSW. That's in addition to coal, gas and hydro generation in Qld. Needless to say, oil isn't cheap.
A point about pricing and dispatch is that different generators (businesses owning power stations) take very different approaches. As some random examples:
Hazelwood (majority owner Engie) almost always just sits there and generates. Price is whatever the market gives them, they don't generally withhold supply or otherwise try to move the price other than by virtue of simply being there.
Hydro generators (Snowy Hydro and Hydro Tas being the dominant two) are necessarily constrained in terms of total output. That is, they can't run constantly 24/7 at maximum output without running out of water (though we do have some individual hydro power stations in Tas which operate constantly but most are set up for higher output intermittently). So they set prices for each station in order to achieve the desired level of output over a given period of time (weeks, months). Eg if we want to run power station x for 60% of the time then set a price that will be exceeded 60% of the time and which will thus result in that plant operating as desired. It's a bit more complex with ramp rates and frequency control etc but that's the basic concept. Work out how much you want to sell (generate), then price in order to achieve that volume.
Then there are those who actively seek to move the price. There's nothing "wrong" about that, it's a market and it's perfectly legal to set prices at whatever level up to the market price cap, but it's generally the larger players who tend to do it mostly. So they'll do things like offering half the capacity of a large, say 500 MW, generating unit at $5 per MWh and the rest at $250 per MWh (random example). Their aim is to push the price up to $250 but their fallback is to keep the plant online, that is to avoid being shut down, if they don't achieve that hence offering half the capacity cheaply.
It's pretty common to see capacity priced just below the expected pricing of competitors with genuinely high cost plant. So a coal-fired plant (cheap) prices just below the cost of diesel when they know that demand is high enough such that other coal, hydro and gas plants won't undercut them on account of already being fully utilised (or they're playing the same game). Since all price bids are made public the next day, and the cost of gas and diesel is no secret either, it's not hard to work out what rival generators are likely to be doing at any given time.
One area where there's a real problem, and this is the point I was referring to before Christmas in relation to the Hazelwood closure, is disclosure of future operations. In terms of plant closures or limitations as of now the following is announced:
Daandine power station (Qld, gas-fired, 33 MW) to close June 2022
Mackay gas turbine (Qld, oil-fired, 34 MW) to close June 2021
Smithfield (NSW, gas, 171 MW) to close 30 June 2017
Liddell (NSW, coal, 2000 MW) to close in 2022
That's it unless you count Hazelwood which wasn't announced until 5 months before the closure date and that's the big concern. It's a big operation and everyone gets just 5 months notice that it's closing. Suffice to say you sure can't build a replacement in 5 months! Full credit to those listed above for giving plenty of notice but the real concern is about what might not be being said? Are there more Hazelwood-like suprises on the way? There's plenty of rumours in the industry about ******** but officially it's business as usual for years to come just as Hazelwood was business as usual for at least the next decade until suddenly it wasn't.
Then there's the question of maintenance outages. Not the minor unpredictable and urgent stuff but the major, long term outages which are planned sometimes years in advance. Let's just say that this Smurf finds it rater interesting that Hydro Tas has publicly announced, via the AEMO (Australian Energy Market Operator), 24 separate major generating plant outages over the next decade (yes really, planned up to a decade in advance). And the total for every other generating company across Qld, NSW, Vic and SA combined? ZERO! Yep, literally zero. Let's say I don't think the full story is being told there. Either that or they genuinely believe they don't need to do any major maintenance (and I sure hope they don't think that's the case).
So there's an issue with lack of disclosure of information. Business as usual in October 2016, then we suddenly find out that the second biggest power station in Vic is closing in 5 months' time. Far too little notice there. And someone IS going to do some maintenance, aren't they? Sure hope so....
Also some of the OCGT's in Tas were run today. That was a purely commercial decision, not required for any technical reason, in response to interstate market prices. Had they not been run then someone else in another state would have supplied that power at whatever price but in short Hydro Tas was offering a lower price than others who had idle or underutilised plant at that time. A commercial decision in all cases. Likewise everyone else with plant running would have been offering supply at lower price than those who had plant sitting idle since price is the basis of dispatch subject to any technical constraints (eg maximum flow on transmission lines) being met.
Today's hot weather in NSW pushed demand there to high levels and that was supplied from Qld and Vic as well as from sources within NSW. With demand fairly low in Vic, Tas and SA the transmission lines Vic - NSW were at their limit transferring power north.
A considerable amount of oil-fired generation, a few hundred MW, was run in Qld today in order to supply power into NSW. That's in addition to coal, gas and hydro generation in Qld. Needless to say, oil isn't cheap.
A point about pricing and dispatch is that different generators (businesses owning power stations) take very different approaches. As some random examples:
Hazelwood (majority owner Engie) almost always just sits there and generates. Price is whatever the market gives them, they don't generally withhold supply or otherwise try to move the price other than by virtue of simply being there.
Hydro generators (Snowy Hydro and Hydro Tas being the dominant two) are necessarily constrained in terms of total output. That is, they can't run constantly 24/7 at maximum output without running out of water (though we do have some individual hydro power stations in Tas which operate constantly but most are set up for higher output intermittently). So they set prices for each station in order to achieve the desired level of output over a given period of time (weeks, months). Eg if we want to run power station x for 60% of the time then set a price that will be exceeded 60% of the time and which will thus result in that plant operating as desired. It's a bit more complex with ramp rates and frequency control etc but that's the basic concept. Work out how much you want to sell (generate), then price in order to achieve that volume.
Then there are those who actively seek to move the price. There's nothing "wrong" about that, it's a market and it's perfectly legal to set prices at whatever level up to the market price cap, but it's generally the larger players who tend to do it mostly. So they'll do things like offering half the capacity of a large, say 500 MW, generating unit at $5 per MWh and the rest at $250 per MWh (random example). Their aim is to push the price up to $250 but their fallback is to keep the plant online, that is to avoid being shut down, if they don't achieve that hence offering half the capacity cheaply.
It's pretty common to see capacity priced just below the expected pricing of competitors with genuinely high cost plant. So a coal-fired plant (cheap) prices just below the cost of diesel when they know that demand is high enough such that other coal, hydro and gas plants won't undercut them on account of already being fully utilised (or they're playing the same game). Since all price bids are made public the next day, and the cost of gas and diesel is no secret either, it's not hard to work out what rival generators are likely to be doing at any given time.
One area where there's a real problem, and this is the point I was referring to before Christmas in relation to the Hazelwood closure, is disclosure of future operations. In terms of plant closures or limitations as of now the following is announced:
Daandine power station (Qld, gas-fired, 33 MW) to close June 2022
Mackay gas turbine (Qld, oil-fired, 34 MW) to close June 2021
Smithfield (NSW, gas, 171 MW) to close 30 June 2017
Liddell (NSW, coal, 2000 MW) to close in 2022
That's it unless you count Hazelwood which wasn't announced until 5 months before the closure date and that's the big concern. It's a big operation and everyone gets just 5 months notice that it's closing. Suffice to say you sure can't build a replacement in 5 months! Full credit to those listed above for giving plenty of notice but the real concern is about what might not be being said? Are there more Hazelwood-like suprises on the way? There's plenty of rumours in the industry about ******** but officially it's business as usual for years to come just as Hazelwood was business as usual for at least the next decade until suddenly it wasn't.
Then there's the question of maintenance outages. Not the minor unpredictable and urgent stuff but the major, long term outages which are planned sometimes years in advance. Let's just say that this Smurf finds it rater interesting that Hydro Tas has publicly announced, via the AEMO (Australian Energy Market Operator), 24 separate major generating plant outages over the next decade (yes really, planned up to a decade in advance). And the total for every other generating company across Qld, NSW, Vic and SA combined? ZERO! Yep, literally zero. Let's say I don't think the full story is being told there. Either that or they genuinely believe they don't need to do any major maintenance (and I sure hope they don't think that's the case).
So there's an issue with lack of disclosure of information. Business as usual in October 2016, then we suddenly find out that the second biggest power station in Vic is closing in 5 months' time. Far too little notice there. And someone IS going to do some maintenance, aren't they? Sure hope so....
