Thai Energy Minister Pongsak: Blackout Was 'unavoidable'

[jacko45k]

All politicians are liars!

He was probably supplied with a completely factual report by Engineers, but as a politician realised he couldn't use it.

[Traveling Sailor]

"Thanit Sorat, secretary-general of the Federation of Thailand Industries, said the government should ensure that a similar event would not recur and it should find out which party would be held responsible for this instance."

Responsible party? In Thailand? I won't hold my breath.

[TallGuyJohninBKK]

lightning striking a high-voltage transmission line... There are two such lines but the other one was under maintenance.

All the original news reports said there was just a single line connecting the Central and Southern regions...

Now suddenly, the news reports say there are two... but the other one was out of service...

Can't tell who's doing a crappier job... the journalists...or the government.

And it takes them a full day-plus to come up with the lightning explanation???

I would say one HV tower but double circuited. No HV line comes with a single circuit as far as I know and as far as I have experienced. There should be 4 lines all together or more. Two lines, 230kV lines had failed earlier. I would say the same failure mode i.e. overloaded or overcurrent as opposed to what the authority wanted us to beleive, i.e. lighting strike.

Two HV circuits are always conveniently separated to make them as almost totally independent from each other. This means a single lighting strike on one of the lines the other line will not be effected. Unless two strikes just happen to hit the two lines within the duration of 30 minutes.... Then both lines can be considered fail at the same time

It is easier for me to beleive that one of the 230kV lines had been overloaded much earlier. By right the authority should curtail load in the South to ensure the healthy 230kV line will not carry greater than 50% of its capacity. But no pro active load curtailment was carried out. The grid dispatcher took chance to load the healthy line up to 100% or so although the normal rating should be around 50% (The N-1 stability requirement). With very little safety margin left, then anything could go wrong. Something when wrong after that. Thus the two lines were off.

My justification is that even the more powerful double circuited 500kV HV line could not stand the load (they tripped too later) then what chance that a 230kV double circuited could stand it?

That sounds like a more plausible explanation vs. lightning... But my continuing question is WHY??? Or in your scenario, why were the line/lines suddenly overloaded on that one night???

That night wasn't especially hot. The time of the failure was in the evening well past what likely would have been the peak demand usage period for the day. And I can't imagine the demand that day was significantly different than what it would have been the day before, or week before or two weeks before.

So, that kind of leads me to suspect something else happened? What that something else was, I don't know. But just a long term trend of growing power demand in the region isn't going to cause a sudden one-off regionwide blackout. There had to be some triggering factor... whatever that may have been.

[bangon04]

All politicians are liars!

"Various agencies have now given conflicting information,"

[ResX]

lightning striking a high-voltage transmission line... There are two such lines but the other one was under maintenance.

All the original news reports said there was just a single line connecting the Central and Southern regions...

Now suddenly, the news reports say there are two... but the other one was out of service...

Can't tell who's doing a crappier job... the journalists...or the government.

And it takes them a full day-plus to come up with the lightning explanation???

I would say one HV tower but double circuited. No HV line comes with a single circuit as far as I know and as far as I have experienced. There should be 4 lines all together or more. Two lines, 230kV lines had failed earlier. I would say the same failure mode i.e. overloaded or overcurrent as opposed to what the authority wanted us to beleive, i.e. lighting strike.

Two HV circuits are always conveniently separated to make them as almost totally independent from each other. This means a single lighting strike on one of the lines the other line will not be effected. Unless two strikes just happen to hit the two lines within the duration of 30 minutes.... Then both lines can be considered fail at the same time

It is easier for me to beleive that one of the 230kV lines had been overloaded much earlier. By right the authority should curtail load in the South to ensure the healthy 230kV line will not carry greater than 50% of its capacity. But no pro active load curtailment was carried out. The grid dispatcher took chance to load the healthy line up to 100% or so although the normal rating should be around 50% (The N-1 stability requirement). With very little safety margin left, then anything could go wrong. Something when wrong after that. Thus the two lines were off.

My justification is that even the more powerful double circuited 500kV HV line could not stand the load (they tripped too later) then what chance that a 230kV double circuited could stand it?

That sounds like a more plausible explanation vs. lightning... But my continuing question is WHY??? Or in your scenario, why were the line/lines suddenly overloaded on that one night???

That night wasn't especially hot. The time of the failure was in the evening well past what likely would have been the peak demand usage period for the day. And I can't imagine the demand that day was significantly different than what it would have been the day before, or week before or two weeks before.

So, that kind of leads me to suspect something else happened? What that something else was, I don't know. But just a long term trend of growing power demand in the region isn't going to cause a sudden one-off regionwide blackout. There had to be some triggering factor... whatever that may have been.

Assuming you have the current peak demand 2300MW. The maximum that the grid could take is 2400MW. The peak demand gradually increases from the current peak to the new peak if your GDP is not zero or less. It is a matter of time when the peak demand will exceed 2400MW. If you don't have any additional power to feed the demand then the right thing to do is to suppress the peak demand to be at 2400MW at most by cutting down supply to consumers at the right time and the right consumers. Why now? I don't know. If not now then it could be next week, next month, etc.

"But just a long term trend of growing power demand in the region isn't going to cause a sudden one-off regionwide blackout. There had to be some triggering factor... whatever that may have been"

That depends on how competent the person in charge to decide up front plant up and to forecast the expected demand growth. A power plant has to be constructed between 4-5 years before you really need it. Somebody might have forgotten to do this 5 years ago I supposed.

" isn't going to cause a sudden one-off regionwide blackout"

It takes the system to lose 10% of the generation for the entire grid to split apart or to undergo major under frequency load shed . Under such condition, some areas may survive some may not... It is hard to see such scenario under the normal condition since one of the grid codes has spell it out cleary about the need to limit loss of load under single major fault shoult be 5% of the total demand capacity or less. So you need to have two major faults that happen within the duration of 30 minutes due to two isolated reasons to trigger the major grid failure. It is like the odd to have both airplane engines to fail at the same time for two isolated reasons. But then as the grid comes closer to its capability limit, the equation may change.

[Thai at Heart]

Not really sure I understand the problem as explained by the government.

Choice A: Lightning strike. Hard to buy, as there are high voltage transmission lines all over the place, and endless lightning storms. A strike to a transmission line would seem to me to be a regular occurrance.

Choice B: Some kind of terrorist attack. The government definitely does not want to go down that path.....

Choice C: Having to explain that there actually is insufficient power available for the south. A great strategy if you want to push a new power plant down there, but would reek short term havoc upon any company deciding if they want to locate their business in the south.

Ahh decisions decisions....

I go with insufficient supply. Just consider how much extra demand has come online in 10 years with industry, tourism and domestic residences and no new power stations.

[Thai at Heart]

lightning striking a high-voltage transmission line... There are two such lines but the other one was under maintenance.

All the original news reports said there was just a single line connecting the Central and Southern regions...

Now suddenly, the news reports say there are two... but the other one was out of service...

Can't tell who's doing a crappier job... the journalists...or the government.

And it takes them a full day-plus to come up with the lightning explanation???

I would say one HV tower but double circuited. No HV line comes with a single circuit as far as I know and as far as I have experienced. There should be 4 lines all together or more. Two lines, 230kV lines had failed earlier. I would say the same failure mode i.e. overloaded or overcurrent as opposed to what the authority wanted us to beleive, i.e. lighting strike.

Two HV circuits are always conveniently separated to make them as almost totally independent from each other. This means a single lighting strike on one of the lines the other line will not be effected. Unless two strikes just happen to hit the two lines within the duration of 30 minutes.... Then both lines can be considered fail at the same time

It is easier for me to beleive that one of the 230kV lines had been overloaded much earlier. By right the authority should curtail load in the South to ensure the healthy 230kV line will not carry greater than 50% of its capacity. But no pro active load curtailment was carried out. The grid dispatcher took chance to load the healthy line up to 100% or so although the normal rating should be around 50% (The N-1 stability requirement). With very little safety margin left, then anything could go wrong. Something when wrong after that. Thus the two lines were off.

My justification is that even the more powerful double circuited 500kV HV line could not stand the load (they tripped too later) then what chance that a 230kV double circuited could stand it?

That sounds like a more plausible explanation vs. lightning... But my continuing question is WHY??? Or in your scenario, why were the line/lines suddenly overloaded on that one night???

That night wasn't especially hot. The time of the failure was in the evening well past what likely would have been the peak demand usage period for the day. And I can't imagine the demand that day was significantly different than what it would have been the day before, or week before or two weeks before.

So, that kind of leads me to suspect something else happened? What that something else was, I don't know. But just a long term trend of growing power demand in the region isn't going to cause a sudden one-off regionwide blackout. There had to be some triggering factor... whatever that may have been.

Why couldn't peak demand in an area with combined tourism and industry be at night.

10mn people coming home for a hot shower and turning on the ac could add on top of industrial activity to make a peak? Couldn't it?

[JetsetBkk]

Truth is, they have power plants all around the south, and there is not "one" cable or whatever that would knock out the power to the whole south. This was a planned event, as the powers that be hate the south, because it's a stronghold of their opposition. This gov't is asking for a fight, and they won't win.

[ResX]

"Why couldn't peak demand in an area with combined tourism and industry be at night".

"10mn people coming home for a hot shower and turning on the ac could add
on top of industrial activity to make a peak? Couldn't it?" TAH

10mn...ahhh...quiet likely. Furthermore, the South was at it weakest condition without those two 230kV lines. I have estimated there should be at least 6 lines altogether, excluding any line from Malaysia for the South grid to remain healthy if the authority decides against construction of additional plant within the South grid. With two remaining lines out of the desired six, the authority should do something drastic to make the grid healthy.

Edited May 23, 2013 by ResX

[TallGuyJohninBKK]

I don't know the exact power use demographics here in Thailand...

But in my home country, the peak use hours usually are mid afternoon tapering up and then tapering down toward dinner time.

But more to the point, electric use usually is driven a lot by temperature and resulting air con usage. And it doesn't seem to me that the evening of the outage was especially warm compared to any other day in the past month.

If it was simply growing demand, then I fail to see why the same thing wouldn't have happened the day before, two days before, the week before, etc. No, I continue to believe there was some human element to this, either the grid operators mis-managing their loads in a way that crashed the system, or outside tampering with the line/lines.

[Unkomoncents]

All politicians are liars!

Ah, but in the Kingdom, an unusually informed public endowed with a social ethic promoting the concept of truth helps to ensure that the most obfuscatory, dishonest politicians are prevented from spreading egregious untruths and obvious circumlocutions.

[Unkomoncents]

I think they should be looking at more Wind powered Turbines instead of dirty coal fired plants. There are wind farms just coming on line in Korat and one in Nakhon Si Tamarat. due for completion in a few months. Wind farms are needed along the Andaman coast to assist with increased Power usage in the area.

Wind turbines are expensive, loud, unsightly and inefficient. The fact is that the human mind is going to have to come up with better energy alternatives than wind turbines. Those things break and they are difficult and expensive to maintain. They don't actually provide all that much power and they interfere with migrating bird patterns and they seriously mar local habitats. A field of turbines may pollute less than a coal-plant but other considerations often have some governments tripping over themselves to find alternatives to the wind turbines themselves.

[ResX]

I don't know the exact power use demographics here in Thailand...

But in my home country, the peak use hours usually are mid afternoon tapering up and then tapering down toward dinner time.

But more to the point, electric use usually is driven a lot by temperature and resulting air con usage. And it doesn't seem to me that the evening of the outage was especially warm compared to any other day in the past month.

If it was simply growing demand, then I fail to see why the same thing wouldn't have happened the day before, two days before, the week before, etc. No, I continue to believe there was some human element to this, either the grid operators mis-managing their loads in a way that crashed the system, or outside tampering with the line/lines.

You have to consider the fact that South grid was at the weakest after the two 230 kV lines were out of order.

[Longtooth]

Well, you can put a "scrubber" on the stack of a coal fired plant. Particulate pollution is cured. Quite expensive. Don't know the number. There is still the CO2 pollution, but that's where "modern" "civilization" seems to be at.

[kruangfaifar]

Two things that Thailand can appreciate about this incident. 1. Restoration time of 4 hour is probably one of the fastest in the world for the sub grid of that size. 2. Fundamental grid protection that is called major area saparation works well. Otherwise entire Thailand is would have been in the dark during that day. Do appreaciate this. Don't take thing for granted.

On the negative site.... No it is not true such incident was unavaoidable. You need at least two major mistakes before the sub grid can go down. One single major mistake won't do that job.

So let we see what could go wrong.

As it was mentioned the 230-kV line was failed due to lighting strike. Why don't you put eveidence to support this hypothesis? You can do it since any major lighting strike on any HV lines will always trigger surge diverter protection to operate. The function of surge diverter is to ground fault current that is triggered by excessive voltage uild up. Lighting strike on on a transmission line ultimately will increase the line voltage above the maximum allowable limit. When this limit is violated a surge diverter makes a complete electrical circuit from the HV line to ground. Thus it prevents further increase in line voltage, before high voltage protection operates to isolate the line. There are dozens of such protection in the Sourth. At least one protection for each generating unit. Let you find out any of them operated. Your operators would not fail to see once the surge diverter operate. They should have heard the noisy "booommmm" sound followed by ground shaking. It migh take not more than 0.5 seconds.

Or...just read the surge diverter counters. The counter will increase by 1 for each time after the protection operates.

The total peak demand capacity in the South is 2500MW. The area can only supply up to 1600MW. So the South is net importer of power from its neighbours by 900MW. I came to know that the South imports 0-150MW, via a double circuit HVDC, from Malaysia grid. That is fine as long as it never allows any single line to carry greater than about 5% of its maximum real time generating capacity. In this case 5% of 2500MW, i.e. 125MW per line. This requirement applies to all transmission lines that feed power to the South.

Here is my suggestion. The South requires additional generating capacity at least 900MW. It still can import from Malaysia grid by at most 150MW double circuited (or 75MW/line) . So it can import the remaining 750MW via the at least 6 independent lines, excluding HVDC tie line with Malaysia grid. Has it been done? I don't know. As far as I can see only 4 lines availabe namely a 230-kV double circuited line, and a 500kV double circuited line from the central. So there is a shortage of two more lines as far as I can see. I can be wrong anyway. But if I'm right about my assumption that only 4 lines are avilable to feed power to the South, excluding 2 lines from Malaysia grid, then the South has already breached its maximum generating capacity to meet its new peak demand. Based on my estimate, the total demand that South grid could provide is 2300MW at most. So under the current scenario the South has been overloaded by 200MW. "Coincidently" the recent blackout has something to do with line overloaded.

What can be done? 1. Build new power plants least by 500MW in the South over the next 5 years. and 2. If possible buy more electricity from Malaysia, at most 50MW more. 3. Limit peak demand up to 2250MW, assuming Malaysia is willing to provide additional 50MW (I doubt about it at least for now) via load curtailment exercise. 4. Promote power saving at least during peak hours of the day.

Even if I'm wrong with active power flow balance triggered failure, there is another potential failure mechanism that needs to be reckon, that is called the voltage sag induced failure. The South grid is very exposed to it too at the moment. That tells how important to have at least one power plant to be constructed in the South.

Good Post. Its nice to see a post from somebody who knows what they are talking about, A couple of points to add.

• The OPGW should have taken the hit from the lightning strike before it got to the line itself. Something must have failed in order for the line to trip.
• Addition of additional lines to Malaysia may help the problem with the Thai grid but may not be politically acceptable to Malaysia. Malaysia has power plant projects in the pipeline which may have problems getting EIA approval if Malaysia is selling power to Thailand in preference to satisfying home demand
• EGCO are building a new 900MW gas fired plant at Krabi in Nakon Si Thammarat to replace the existing 789 MW plant whose contract expires in 2016. This will help the situation a bit
• EGAT is building a 782MW expansion to it's existing 720 MW gas fired plant at Chana in Songkla which will help a lot
• The EGAT Governor's suggestion to build a new transmission line from Ratchaburi is a valid suggestion but it will take years to aquire the Right of Way, get environmental approval and build
• EGAT's plan to build a coal fired plant at Krabi has a number of advantages including 1) diversifying risk (using coal from a number of potential overseas suppliers ),2) Takes pressure off the gas supplies which are already getting limited (and subject to Burma supply uncertainties) and 3) the addition of large generators to the system will improve system stability and hence reliability as well as 4) competitive energy prices. However obtaining Environmental approval will be a challenge and may kill the project.
• I think the time is coming pretty soon when people are going to have to choose between building Nukes or Coal fired plant because the gas will not last forever and renewable power is not going to solve the problem anytime soon.
• I wish all the TV posters who make embarassingly uninformed cynical comments about power system planning in Thailand would Google "Thailand PDP 2010", download and read the latest version then give us your comments (if you can understand it:

[OzMick]

To add a different perspective on this debate, I read an article a few days ago about power generation in Germany. Nuclear and fossil fuels are slowly be phased out and being replaced by solar power and other eco-friendly alternatives. Apparently Germany, not as close to the equator as Thailand, is a world leader in the use of solar power. Rather than build a coal fired power station, look at installing solar panels on buildings, certainly new buildings, and do some work on the power distribution grid to eliminate waste.

Didn't you notice that the power shortage was at night?

[Valentine]

So, it turns out the region wide blackout could have been avoided if those in control had stopped passing the buck. Contingency plans were in place for such an eventuality but no one was prepared to authorise their use.

[kannot]

"Thanit Sorat, secretary-general of the Federation of Thailand Industries, said the government should ensure that a similar event would not recur and it should find out which party would be held responsible for this instance."

Responsible party? In Thailand? I won't hold my breath.

Then send them to the "electric" chair..............if any is available

[johnlandy]

"Energy Minister Pongsak Ruktapongpisal yesterday described Tuesday evening's blackout in all 14 southern provinces as "unavoidable" but did not come up with long-term measures to prevent a repeat in the region"

Ah, Thai politicians at their best.

Yes and another reason why Thailand will remain a 5th world country probably for the next millenium.

Singapore has more lightening strikes than any other country in the world (every 2nd day on average) and I never experience a blackout there (and I lived and worked there)

The electrical supply / reticulation in Thailand is at best haphazard (like many things in the realm) so what can be expected.

[Robby nz]

Those who recommend wind turbines have a look at that.

http://toryaardvark.com/2011/11/17/14000-abandoned-wind-turbines-in-the-usa/

It seems from the latest news that the baddies in the south have picked up on the idea of power blackouts.

[ginjag]

Unavoidable ????? Having extra power re directed from Khorat, The word infrastructure comes to mind, usually one would see that extra power is available when planning resorts of the souths magnitude, NOT the usual excuse---unavoidable.

When you have persons in charge of departments, they should be qualified to forsee future problems. BUT as water management minister proved, FLOODS-excuse was unusual rainfall. these are 2 examples, an so on. carry on as usual government and it will be to your downfall. The south was not important when it came to votes, So it is vital you keep the Issan and Chiang Mai free from mega probs.

[TallGuyJohninBKK]

You certainly could argue the south blackout was UNAVOIDABLE... if you start with the premise that the people operating the power grid here are buffoons who don't know what they're doing, how to properly upkeep their infrastructure, or how to operate a system that is not prone to recurring failures, both local and sometimes more broadly.