Monday 12 September 2016

Over 40% of Wind Energy Shutdown Last Night

by OWEN MARTIN

Last night, over 40% of wind energy produced was shutdown or curtailed during a spell of gale force winds across the island of Ireland. This episode clearly shows the limitations of relying too much on an intermittent source of energy like wind. Billions of euros worth of turbine installations become worthless at both low wind and at high wind.   

Figure 1


The reason for the shutdown of so many wind turbines can be clearly seen in the System Frequency charts before and after the wind shutdown. 

As the gales gathered in strength on Sunday evening, maintaining the frequency of the grid became more difficult :


Figure 2


The zig zag patterns in the Figure 2 show how frequency fluctuated between 49.9 and 50.1 Hz. The dips represent periods of too much wind when system inertia drops (due to lack of conventional generation such as coal or gas). Should frequency drop below 49.7 Hz then a blackout may occur, so Eirgrid rectified this by shutting down some of the wind and allowing more conventional generation into the system. The frequency then rises again to 50Hz. Gas turbines are forced to ramp up and down more often to maintain system stability during such periods thus pushing emissions up and negating some of the benefits of  having all the wind in the first place. 



Figure 3

Figure 3 shows what happened when over 40% of the wind output was shutdown and there was more manageable levels of wind, in this case about 1,500MW. The frequency is very stable and there is little risk of blackouts. This has been normality in the grid for many years. Compare it with Figure 2. This is the future. It will certainly test engineering skills to it's limits. Gas turbines will have to function under greater strain than before. It will cost a lot of money. There can no longer be a guarantee that the electric kettle will boil when you want it to. 

The other option Eirgrid have to maintain a stable frequency in these situations is to cut demand - which is in effect a blackout under another name. The future is renewable. The future is green. I'm at a loss to figure out how this is "progress".

3 comments:

  1. The question is, why is science, engineering and mathematics shut out of policy making today. Wind is just one symptom of it just to make money by loading the cost on consumers. As society develops, it becomes more reliant on electricity, as it does we can assess if there is a mob in charge of it all. A mob of the great and the good typified by Al Gore and Mary Robinson but there are other well know controllers with stooges Eamon Ryan and the Pope. Hillary Clinton has Parkinson's disease for over 5 years. Poor woman, she will grow physically weaker. Last Sunday, the mask slipped at Ground Zero. Do you seriously believe the mob were not aware of this? The nomination was rigged, by whom? Why was Biernie the only challenger? Why was he the victim of a rigged convention. There were 17 on the Republican side. Hillary is not the real Democratic candidate, the real candidate is Tim Keane. If the Democrats take the White House, Keane will very early on be President. Tis he we should be looking at, not Hillary. He is the puppet of the mob, not their preferred man, their man. Brexit was a rejection of this by observant voters. The EU is controlled and they control America.Trump is just a Brexiter with money. He needs good security, very good security.

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  2. The last few days in the UK have seen the opposite wind problem, anticylonic gloom killed both wind and solar for around 50 straight hours, did the same happen in Ireland? and is archived electricity data for each generator available to analyse for Ireland?

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  3. The ten turbine 11 me wind farm at Gearteaneanne Bailieboro was shut down completely yesterday. I passed at 11.30 am and again at 1.50 pm and all were stopped. It was very windy, about 18 mph I guess. But not gale force. Ideal. I suspect they are creeping. (15 years ) old. So better get paid to turn off than force then to generate at high output. Nice money to produce nothing.

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