How Close is Ireland to Blackouts ?

 

                                  Chart 1 - The green line includes all potentially available capacity whether currently in use or not. Some adjustments have been made to the red line to take account of the temporary loss of two gas and one oil generators . 

The above graph shows how Ireland's electricity supply position has evolved since the height of the building boom in 2006. The green line shows the total generation capacity that consumers must pay for including wind energy. As you can see the gap between the green line and peak demand in blue has increased exponentially in tandem with the building of new wind farms in yellow and new power stations in red. This gap is a large part of the reason why electricity bills have soared in recent years as the capital element of all of this capacity must be financed through bills regardless of how much energy they produce. So with all of this excess capacity, how is it that we are facing the prospect of blackouts? 

The red line is dispatchable plant, that is, plant that can be switched on at a moment's notice as required. The main ones in Ireland are gas, coal and oil power stations. The interconnector to England (EWIC) is also included in this however it's debatable how dispatchable this is in light of recent events (more on this later). Peat is also dispatchable but two of those power stations were closed down in 2020 leaving only one remaining peat station in Edenderry which also runs on biomass. It is due to be closed down in 2023. It has now finally being accepted by almost everyone (apart from the Green Party Energy Minister ?) that wind is not dispatchable and during long periods of low wind as we have had this year it is really the red line that we are relying on to keep the lights on.

The red line takes a noticeable dip after 2020. This is to take account of the loss of three power stations during 2021 - Huntstown 400MW, Whitegate 444MW and Tarbert 243MW. This has returned us to 2007 levels of dispatchable plant. This shouldn't present a serious problem, we managed okay back then. However, there are two main differences between now and back in the Tiger days :

1) Peak demand has increased by about 10%. The peak of 5,357MW was reached in December 2020. It is likely that this will increase further this winter which means the gap between the red and the blue line in Chart 1 will narrow even further. 

2) The rate of forced outages has increased dramatically in recent years. According to Eirgrid, the forced outage rate went from a low of about 3% in 2016 to a high of about 16% in 2021. The forced outage rate is the rate at which power stations are breaking down. Power stations are becoming less reliable and not just old ones. One reason for this is that they are switching on and off too much to balance the wind (more here) . 

The situation then is precarious enough but what happens if the UK does not have spare energy to give to us over the interconnector ? This has become a greater risk as energy shortages have recently become a major political issue in the UK. Chart 2 shows what happens when the EWIC is no longer available :

Chart 2

There is now a very small gap between the red and blue lines. 353MW to be exact. Which is about the size of a single power station. So another power station outage would leave us on the precipice and if the winter is a cold one demand will surely rise pushing us over the edge into blackout territory. 

To sum up here, it would take six events occurring at the same time to leave us in a very dangerous position - three of those are the three currently unavailable power stations not being repaired in time for winter, the fourth is the interconnector becoming useless, the fifth is either another power station breaking down or demand rising higher than last year. The trend for the fourth and fifth events is going the wrong way in all cases. The likelihood however of all 3 power stations not being repaired in time for winter is fairly slim although I have a feeling Whitegate may not be repaired by mid November as scheduled.

The sixth event is perhaps the biggest variable of all, the yellow line in the charts - wind energy. If there is plenty of it then in theory the majority of these events occurring simultaneously would not pose such a major problem. But if we have another lull as we have had this summer then that is a different story.

I say, in theory, because it is slightly more complicated than that. Certain power stations are required to be operating at all times to maintain the stability of the grid. Currently that includes Moneypoint coal power station. Moneypoint happens to be the oldest power station on the grid so there is a risk to the entire grid if it alone suffers an outage. No amount of wind energy can replace the inertia that Moneypoint provides to the system. 

In any event, the demand of large energy users will most likely be cut before we get near the precarious position of all or most of these events occurring together. 

Demand management they are calling it. Which is another form of blackout, just with a nicer name . 

Record Prices hit the Irish Electricity Market

 On Thursday the 9th September, prices in the All Ireland Electricity Market hit record highs of €4,680 per MWh, well over 20 times the normal price :

The scale here is from €0 to €5,000 MWh

What a normal day looks like, prices rise to about €150 MWh

These prices may have had something to do with the UK switching on coal plant that same week, the cost of which can be very high. Margins are set to get even tighter in the UK as this week one of the interconnectors to France went on fire causing wholesale prices to rise even higher there. Low outputs of wind energy have plagued both Ireland and the UK for many months now. In essence, high prices in the electricity market go hand in hand with low amounts of reliable generation.

There have been three Amber Alerts and seven Notifications of Tight Generation Margins issued this month in the Single Electricity Market (SEM). An Amber Alert means there was expected to be enough energy to meet demand, but possibly not enough in reserve should something go wrong. They can also be issued if there are significant frequency / voltage deviations which can happen when there aren't enough large power stations on the grid. The notification of Tight Generation Margins seems to be a prelude to an Amber Alert. 

System Alerts can go from Alert (Amber) to Emergency (Red) to Blackout (Blue) and finally to a Restoration state. Up to the end of August of this year there have been six system alerts on the grid. In the previous decade, they averaged just one per year.

Amber Alert With More Generation ?

 Eirgrid warned this week of an Amber Alert due to high peak demand, a loss of a number of generators and low wind generation :

“There were a number of reasons that gave rise to Wednesday’s alert. Firstly, two of the three units at Moneypoint, the country’s largest power station, suffered technical failures and were not available. This resulted in the loss of 570 megawatts of electricity.

“Generation at Whitegate power station in Cork totalling 450 megawatts was also unavailable due to technical issues. A 243 megawatt generator at Tarbert power station was called up but could not respond due to technical problems. 

“The electricity market was set up for Ireland to export renewable energy via the two interconnectors (EWIC in the South and Moyle in the North) linking Ireland and GB.

“Following the issuing of the amber alert we were able to reverse the flows on the Moyle Interconnector and on EWIC shortly after that. There was also a drop in wind generation greater than was forecast prior to the alert being issued.

“There was no loss of electricity during the alert which ended by 6.20pm on [Wednesday],” the spokesman explained.

 Apparently the last time we hit such a demand was back in 2010 but there was no mention of an alert back then. In 2010 there was 1,405MW of wind installed on the grid. In 2019 this reached 4,235MW (+2.8 GW). The 500MW EWIC interconnector was commissioned in 2012. 

So the question has to be asked, how is it that with 3.3GW of additional generation equipment, we are now struggling to meet demand?