i cant count. 4 years ago
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i cant count. 4 years ago
Big batteries are the go.
Taylor reckons a big gas generator, rather than a big battery, is needed to avoid load shedding, and he singled out South Australia as the prime example. But here’s the irony: South Australia has not had any significant load shedding since February 2017, and that event was caused by the failure of the state’s biggest gas generator to switch on when needed. It was that very failure that directly led to the billionaire tweets between Cannon-Brookes and Musk, and the construction of the Tesla big battery.
It’s also interesting to note that the last big loading shedding event in Australia happened in West Australia in January this year when more than 95,000 people had their power cut off for several hours. According to AEMO, that was the result of a failure at the modern gas unit at Kwinana, and a cascading series of events involving other gas generators. It probably would not have happened had there been a big battery in the local grid.
you need to get your facts right bob. its wasnt a problem with the generator, it was a problem with the switching yard.Quote:
Originally Posted by bob10
Some facts on the S.A. blackout.
AEMO’s forecasts for temperatures and wind energy in South Australia on the afternoon of February 8 were hopelessly wrong. And when the crunch came after the operator realised its mistake, key fossil fuel infrastructure failed or melted down in the heat, or in the case of Pelican Point, simply did not get switched on.
And then, to make matters worse, the local network operator completely stuffed up the management of the load shedding due to “software” issues – meaning that three times more people lost power than needed.
Regulator sues South Australia's biggest gas unit over role in blackouts | RenewEconomy
oh i see the problem, you are using renew economy as a source of facts.Quote:
Originally Posted by bob10
It is this type of reporting that leads to confusion. The average Joe consumer reading this will believe that these things produce electricity by some magical means without putting in any other form of energy!
Probably beyond the scope of this Forum to go too far into just what these machines achieve, and how they achieve it. It all comes down to an AC systems "Power Factor", which is also often referred to as "Wattless Current". Any AC induction type generator produces electricity at what is termed a "lagging power factor". That is to say the voltage and the current produced are not in phase, or rise and fall together, rather the rise of the current as seen on a sine wave, follows the rise of the voltage by some degree less than equal or in phase, also called "unity". If you have a small portable generator it may have on the nameplate: PF .8, which means that the rated output is only achieved at .8 PF(or better).
The problem with power grids is that the "wattless current" has to be produced, which means all the infrastructure, plus the generator out put capacity, has to be big enough to cope with poor power factors.
What they are referring to in this article is a machine that runs from the grid at synchronous speed,(that is at grid frequency), but its shaft is not connected to anything. Its field winding has to be separately excited with a DC current, and the result is it acts like a big capacitor and as such runs with a LEADING power factor.(greater that 1.0) The aim is to improve the overall PF of the grid by "absorbing" some of the useless reactive Kvars of the grid by simple offset. Some also claim that it also "stabilises" the voltage, but if it does that is not its prime function.
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Big spinning machines arrive in South Australia to hasten demise of gas generation
Big spinning machines arrive in South Australia to hasten demise of gas generation | RenewEconomy
S.A. leading the way with roof top solar rules
.Rooftop solar enters brave new world as South Australia leads shift to tighter rules | RenewEconomy
Apparently they are an interim measure.Quote:
Originally Posted by Old Farang
Essentially, these syncons – which are also being installed in Victoria, NSW and Queensland, and have already been in Tasmania – are seen an interim measure as the grid transitions from one dominated by large synchronous machines (coal, gas and hydro) to one dominated by inverter based technologies (wind, solar and batteries).
Not sure just who sees them as an "interim measure". For grid power generating stations their sole purpose is the "bottom line". They are not put there to make a grid more reliable, or to provide customers with cheaper power.Quote:
Apparently they are an interim measure.
Essentially, these syncons – which are also being installed in Victoria, NSW and Queensland, and have already been in Tasmania – are seen an interim measure as the grid transitions from one dominated by large synchronous machines (coal, gas and hydro) to one dominated by inverter based technologies (wind, solar and batteries).
The simple fact is, the more that the power factor can be kept towards unity, the more the return is to the operator because the fuel input, regardless of what form it is, is not being wasted generating "wattless power".
The argument being touted concerning "renewables" is only valid because the wind and the sun are "free". The infrastructure still has to have the capacity to tolerate a poor power factor, but it is a one off cost only built into the design of the system.
For "average Joe consumer" power factor can be thought of as two horses pulling a cart, they are most efficient when pulling in the same direction (unity/PF of 1.0) not at an angle to each other.Quote:
Originally Posted by Old Farang
The article refers to "synchronous condensers" for old petrol car owners this should remind them of points and condensers, a condenser is a capacitor, power factor correction can be achieved with capacitors. I think the reason they have opted for the synchronous motors, is they can alter phase angle (and even frequency which is pro'ly what they'll be used for in this case) , as they do in America because they don't have a national grid, so states buy in power from other states that are not synchronised and use a synchro to align with their local power.