Coal and Oil to the Rescue During Cold Weather

Last week was one of the coldest spells of weather here in Ireland of recent years. As usual with very cold periods, wind generation was low. The grid operators struggled to keep the lights on and many amber alerts were issued.

Wind energy contributed about 20% of the power on average. 

Whitegate Gas power station was and still is out of action which is surprising for a modern ten year old power station. Gas power still provided the majority of the power in the grid mix -  around 50%. 

Wind energy last week - only a small portion of the total installed wind capacity of 4,000MW was available at times

 

Coal provided 12% despite only two out of the three generators at Moneypoint functioning.

An internal ESB memo shows that national grid operator, Eirgrid, asked the company to start up one of its three generators at Moneypoint in Co Clare, which had been shut down, to avoid any possible risk of blackouts [Eirgrid].

Starting up a coal generator takes at least 16 hours to start up from scratch (cold start) so presumably this unit was kept ticking over (warm start). This is what many wind advocates do not understand - you simply cannot switch off a large power station and expect to turn it back on again at short notice. 

Imports were only 1% presumably because UK had no surplus electricity of their own.

This then leaves "Other" at 10%. 

There are only two possibilities for what this comprises now that all but one of the three peat power stations have been discontinued - waste to energy and oil/diesel. Only one waste to energy plant is currently in operation at 62MW. So assuming it was running at max output it was providing about 1.5% of the total fuel mix. Edenderry peat power station now operates at about 60MW also (the other half of it's fuel source is biomass) so likewise about 1.5%. Therefore, unless I'm missing something, about 7% of the fuel mix came from oil and diesel generators. 

Which is roughly the portion of fuel mix from the two peat power stations that were closed down. Oil generation has not contributed this much since the 2000s. This amounts to an indictment of the renewable energy program, in that 4,000MW of new wind energy installed cannot replace 230MW of peat.

Based on that, the expectation that Moneypoint coal power station will close down by 2025 is now looking very unlikely.

Overcoming Grid Constraints Fails to Solve Inherent Problems with Wind Energy

In 2014, the maximum level of wind energy allowed into the grid was 50%. In 2017, this was increased to 60% and by November of last year trials were run at 65%.  So some of the obstacles to higher levels of wind energy such as grid constraints have been partly overcome, which theoretically speaking should result in higher wind outputs from individual turbines (the capacity factor). 

In 2014, the capacity factor for wind was 27%. In both 2016 and 2017, the capacity factor remained at 27% despite the higher wind penetrations allowed. 

An analysis of wind speeds shows that wind speeds were fairly similar for those years, with 2015 being somewhat higher.  I took a sample of six weather stations from around Ireland, the average wind speeds I obtained neatly fitted with the capacity factors for wind. 

Year	2014	2015	2016	2017
Average wind speed (knots)	9.6	10.4	9.3	9.7
Capacity Factor Wind	27%	32%	27%	27%
Max wind penetration (SNSP)	50%	55% Trial from Oct	55% Perm from Mar	60% Perm from Mar - 65% trial Nov

As can be seen from the last part of the table above, we went from allowing 50% wind into the grid to 60% and by the end of last year 65%. As wind had more access to the grid, we should have seen a higher capacity factor for wind.

This seems to suggest that we have already reached saturation point for wind energy. I would be interested to hear what people think. I have already written about market cannibalisation and diseconomies of scale. Here is strong evidence that supports that argument. Most of the best sites for onshore wind have been used up. The turbine layout at some sites is too dense and newer larger wind turbine models have failed to deliver any significant additional output. And after all, the wind resource itself is limited, particularly in Midland regions. 

Sources

Eirgrid Constraint Report 2017

http://www.eirgridgroup.com/site-files/library/EirGrid/Annual-Renewable-Constraint-and-Curtailment-Report-2017-V1.pdf

Wind speeds from Met Eireann website (in knots)

https://www.met.ie/climate/available-data/historical-data

	2014	2015	2016	2017
Cavan	6.3	6.8	5.9	6.3
Kerry	9.5	10.3	9.1	9.3
Donegal	14.4	15.3	14.3	15.1
Cork	12.2	13.1	11.8	12
Tipperary	8.3	8.8	7.9	8.2
Carlow	7.3	8.2	7	7.3

All stations record wind speeds at 10m above ground level.

Note that total wind output did increase in 2017 by about 18% by adding an extra 530mw of wind capacity, an increase of about 20% on the previous years installed wind capacity. The capacity factor measures the actual output in relation to potential output if the entire wind turbine fleet had been operating at full output for the entire year. So theoretically if wind speeds increase so should the capacity factor. Or if wind speeds stay the same and the maximum level of wind permitted into the grid increases, then capacity factor should also increase.

Technical Problems with High Levels of Wind on Christmas Eve

New Report Describes Total Decarbonisation Dream as Wishful Thinking

On Christmas Eve, wind was providing just over 60% of electricity demand. This is new territory for the Irish grid (or indeed any grid). Eirgrid began trials of allowing a maximum of 65% for wind energy (wind penetration) in November. Wind generation was also exceeding the wind forecast. 

Jolly good I hear you say. However, it can be troublesome balancing this level of wind as other plant are forced to run below their optimum efficiency. The additional unforeseen wind also creates more problems as scheduled plant are constrained off.  Variances in the frequency are a good indicator of just how much trouble these high wind conditions can cause. A stable frequency is required for a stable grid and a certain amount of conventional plant is required to maintain the frequency within a tiny range. 

As the wind level rises, the frequency falls below 50Hz. At around 15:40, some of the wind energy is shut off and the frequency returns again to 50 Hz.


These technical problems have been highlighted in a new report on the German electricity grid (Hidden Consequences of Intermittent Electricity Production).

Another important difficulty caused by intermittency is the increased vulnerability of the electricity grid to instabilities. This is particularly visible in countries that are not so well interconnected like Ireland. An example of a threatening oscillation occurring at a 400MW power generator (24/4/2014 between 21:40:40 and 21:41:00) is shown in Fig. 3 (adapted from M.Zarifakis et al.,  “Models for the transient stability of conventional power generations stations connected to low inertia systems”, Eur. Phys. J. Plus 132, No.6, 289 (2017), op. cit.).

Grid stability is now a major issue around Europe :

Further, if one keeps the current Alternative Current grid technology, a certain minimum amount (~ 20-25%) of “rotating mass” has to be present to guarantee stability.  If this cannot be sufficiently provided using biomass, and if fossil and nuclear based power stations are not allowed, problems will arise. Instabilities caused by large contributions of intermittent power e.g. from wind or solar PV pose a major threat to the stability of the electrical network of a country and to the safe operation of conventional generator systems, as exemplified in Ireland. If no economical solution can be found for such difficulties, conventional backup power based on fossil fuels or nuclear power will necessarily have to remain part of the electricity system.

Their conclusion is in agreement with the work carried out on this blog :

A last point is the economic feasibility of such a system. Germany, with currently an installed capacity of about 90GW in solar PV and wind, has one of the largest renewable systems installed in the world. The cost (including feed-in tariffs, subsidies, extra costs because of court cases due to unfulfilled promises etc…) is estimated between 250 and 300 billion Euros, integrated over the last 10 years. The CO2 reduction on world scale realized by this system is less than 1‰. As discussed above, a 100% iRES without backup or storage systems makes not much economical sense and will lead to a doubling or tripling of the total costs, compared to the conventional system in use now. It is to be expected that not many countries are able to pay for such a costly and inefficient system. The question can thus be raised if the current EU plans for the electricity sector are bound to fail? 

Finally, the electricity sector is only a minor part of the problem. If one wants to completely decarbonise our economy then one should also include other private and economic sectors. Given already the challenge of a 100% renewable electricity system and the complexity of replacing the present primary energy supply based mainly on chemical energy by renewables, this total decarbonisation looks to be wishful thinking, at least at the present stage of technology. Would it not be more useful to invest in research and development of conventional and new energy systems rather than blindly investing in an existing “green” technology which seems bound to miss its goal? The other question is whether decarbonisation should be our primary concern. Is this really the best investment for a better future for mankind, as discussed in B.Lomborg, “Cool It”?A critical assessment of the EU plans is also voiced in countries outside the EU, in particular the United States under the presidency of Obama. Does transforming the present primary electricity supply (based presently mainly on fossil and nuclear sources) into a 100 % intermittent Renewable Energy System, as imposed by the EU, need to be the challenge and moral quest of the 21stcentury? This will for sure affect our society and standard of living if current EU plans are not corrected for the problems that are emerging from the grand renewable experiment in Germany of the recent years.

The full report can be found here : 
http://revue-arguments.com/articles/index.php?id=76

Grid Costs Set to Rise to Meet 2020 Targets

Grid costs will cost households and businesses an additional € 354 million next year as part of a large rollout of grid and transmission networks. The Energy Regulator explains :

The five years from 2016 to 2020 will require continued investment in the transmission system and delivering ongoing infrastructure projects. The PR3 period was characterised by the initiation of a large scale infrastructure delivery programme in order to meet 2020 renewable generation targets

So the transition to the green economy doesn't involve dismantling of the existing fossil fuel system. Instead, it means adding capacity and grid infrastructure paid for by you and me. This is fast turning into a gravy train for whoever has the best idea for extracting more money from electricity bills, or in economic terms, a bubble. 

The same is happening elsewhere in Europe. In Germany, grid costs will soon rise by a whopping 45%-80% as network infrastructure struggles to keep up with all the additional capacity :

http://www.spiegel.de/wirtschaft/unternehmen/tennet-und-50hertz-erhoehen-netzentgelte-a-1113741.html

There is no going back now. We have committed ourselves to a crazy energy policy. No wonder the European Union is no longer as popular as it used to be.

Will The Lights Stay on in Ireland ?

A new report by the European Network of Grid Operators (ENTSOE) has shown that Great Britain may not have sufficient electricity generation capacity by 2020 to keep the lights on. This has a knock on affect here in Ireland where by 2022 it is envisaged that we will become more and more dependent on interconnectors.

ENTSOE have placed Britain at the highest risk level of grid blackouts in EU but state that expensive Capacity Mechanisms may prevent them from happening. For the layman reading, this is due to lack of investment in baseload generation - gas, coal, nuclear. Lack of sufficient baseload generation in UK means interconnectors to Ireland will lie idle (where Ireland is also strapped for reliable means of power to export to UK). 

Eirgrid this year published their generation adequacy assessments up till 2025. 

Take a look at the bottom section which excludes interconnection. Green means we have sufficient generation, red means we don't. By 2022, things start getting tight, by 2023 and 2014 we are in blackout territory, highly dependent on UK to send us spare power. 

Of course, we have spent billions on new wind farms. But as ENTSEO state :

The contribution of RES [renewables] for adequacy purposes is less than for thermal plant.

I've dealt with this concept before - capacity credit.  Wind farms don't keep the lights on, power stations do. 

There is a further problem for the Irish Grid operators - Eirgrid - and that is the new data centres that are been built around the country. They consume lots of power - Eirgrid estimate that if all the data centres that are contracted are built, they will add a whopping 1,700MW on top of peak demand of about 5,000MW. This would mean we get into the red a lot quicker. 

There is a quick fix to this, of sorts, and I hinted at it earlier - Capacity Mechanisms. This involves load shedding - paying factories large amounts of money to close for a period and / or diesel generation which can ramp up alot quicker than power stations. Ireland had about 60MW of diesel generation in 2014 (referred to as Demand Side Units), we now have 230MW ! And Eirgrid have said :

The capacity of Demand Side Units in Ireland has increased to 230 MW, and is set to increase further. 

How ironic that the green revolution, the de-carbonization of our grid, the clean, green future has lead to us using more and more diesel generation - the most polluting form of electricity production. And of course, our neighbours England are also going down this path. 

Incidentally, the data centres will have back up power in the event of widespread blackouts. No, not windmills, yes you guessed it - diesel generators. The new Apple data centre in Galway will have 18 generators with a total capacity of 288MW. The new green revolution is upon us !

Rising Costs of Stabilizing Irish Grid

Synchronous Condenser in Australia (Wikipedia)

As levels of wind energy increase, fossil fuel generators and other devices are been called on to provide stability services to the Irish grid to help prevent blackouts. Its a simple engineering fact that as wind energy increases, the grid loses inertia and the frequency of electricity sent to your home becomes more difficult to control. The frequency of the Irish grid is set at approximately 50 Hertz, give or take about 1 Hertz, and all our appliances will not run outside this small range. 

Large power stations have trip switches that deactivate generators when the frequency moves outside this range so if the grid loses inertia for even a few seconds, there will be a cascade effect as generators drop out. A widescale blackout is the likely result. The rotational speed of wind farms is changing all the time and at different regions and it's because of this that they can't provide inertia to the grid. Gas and coal power stations are classed as synchronous generators because they provide stability to the grid, while wind farms and the East West interconnector are deemed non synchronous generators (SNSP). 

At the moment non synchronous generators are limited to 50-55% penetration in the grid. It is envisaged that this will have to rise to 75% in order to achieve the 20-20 targets. A consequence of this will be less synchronous generators online during high wind periods and increased risk of blackouts. So synchronous generators need to be paid more to maintain stability through what are called ancillary services.     


The diagram below shows that these ancillary or grid stability payments increased from € 24.5 million to € 26 million in the year to April 2016. 

POR means Primary Operating Reserves and SOR Secondary Operating Reserves. POR can step in up to 5 seconds and SOR up to 15 seconds to replace a generator that suddenly drops out. Tertiary Reserves (TOR1 and TOR2) take longer to start but can be maintained for longer time. These reserves are set by the single largest generator that happens to be online at the time, usually the East West Interconnector. However, demand for fast reserves, which are inefficient and high emitters, is increasing with higher levels of wind as wind fluctuations dominate the grid. 

The largest increase was for Reactive Power services. These are mostly provided by synchronous condensers which are able to provide stability in times of large voltage changes due to stochastic wind energy. Engineers at UCD provide a good overview of these devices here.  

Like battery storage units, synchronous condensers are net consumers of electricity but are essential for keeping the lights on with high levels of non-synchronous wind energy.  Adding units that consume more energy over their lifetime that they can generate is a consequence of the wind program and should have been included in a cost benefit analysis, which as we know, was never done.

What about alternatives ? Well, biomass and hydro provide synchronous power as of course does nuclear power. But green lobby groups do not want these and wind lobby groups want us to install more wind, this time offshore. Surely, it's time we looked at other options.

Sources:

1) http://www.eirgridgroup.com/site-files/library/EirGrid/AS_OSC_Report_April2016.pdf

2) http://www.eirgridgroup.com/site-files/library/EirGrid/AS_OSC_Report_2014_2015_Nov.pdf

3) http://www.eirgridgroup.com/site-files/library/EirGrid/OperationalConstraintsUpdateVersion1_35_February_2016.pdf

4) http://erc.ucd.ie/wp-content/uploads/2013/10/IRC_P%C3%A1draig_Daly.pdf