Study shows that renewable energy auctions don't reduce costs any more than feed-in tariffs

A study just published in the International Journal of Sustainable Energy Planning and Management says that renewable energy auctions do not reduce costs of renewable energy projects any more than conventional feed-in tariffs.

See

Renewable Energy Auctions and Tenders: How good are they?

David Toke

Abstract

This paper analyses the performance of two cases of renewable energy (RE) auction/tender systems in an effort to contribute to the evaluation of RE auction/tender systems and to study best practice in their delivery of RE projects. This is done by comparing regimes in different settings, one concerned with Danish offshore wind development, the other concerned with renewable energy development in South Africa. It is found that regulatory factors which promote certainty in deployment, including measures to ensure that projects achieve grid connection, are important in assuring delivery of the programmes. However cost reductions that are associated with renewable energy auctions are not caused mainly by the auction systems themselves, but rather are associated with general declines in the costs of renewable energy technologies. Moreover, the effect of renewable energy auctions systems may be more concerned with limiting renewable energy deployment rather than reducing the costs of energy generated by renewable energy projects that are deployed.

The article can be accessed free of charge at:

http://journals.aau.dk/index.php/sepm/article/view/1197

This is an important piece of work since it contradicts a lot of narratives spread by leading utilities and governments who are anxious to limit the spread of renewable energy. Despite the clear message from Paris that we need to expand renewable energy as rapidly as possible the means of promoting renewable energy now being chosen are much concerned with limiting its expansion. This is being done under the guise of allegedly making the schemes be implemented at a low as cost as possible through 'auctions'. Yet as this study suggests, this system does not reduce prices - that is being done by global technological mechanisms - but what governments want to do is to limit the renewable energy that is deployed, and the auction systems can do this because they cap the amounts of capacity that can be deployed. Big energy companies also like the system since they can dominate auctions more easily.

Another important message brought by the study is that the auction systems need to be designed to maximise certainty for and by developers. Otherwise the schemes who win contracts will not be implemented. This means guaranteeing grid connection conditions for developers and to guarantee that the schemes actually materialise (through a system of penalties for non-implementation of projects).

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Eco-modernism - I've been mugged!

As an academic who has written widely about ecological modernisation - essentially how business can combine ecological protection and development - I feel thoroughly mugged by the recent launch of the so-called 'eco-modernist' agenda. It ended up being associated with people like Owen Paterson, who wants to scrap the 2008 Climate Change Act, and one of so-called eco-modernism's founders, Mark Lynas seemed surprised by this.

But you shouldn't be surprised if you do read the so-called eco-modernist' agenda. Essentially it rubbishes renewable energy, organic farming and generally green movement preferences for tackling environmental problems and proposes as the solution, well, business-as-usual industrialism. Of course it is very pro-nuclear power. So what is new about this version of eco-modernism? Not much it seems.

But ecological modernisation, an academic tradition stretching back to Germany in the 1980s is about reforming industrialism, not beefing up some of its worst attributes. The founder of the school (and those who have written about it since then including myself) are not noted for their pro-nuclear credentials, and they are of course generally highly supportive of renewable energy.

Renewable energy is. of course, at the cutting edge of ecological modernisation. Nuclear is something that is not happening very much, in fact in the UK not at all! All the British state, for example, seems to be able to do at the moment, is to stop the delivery of renewable energy but it cannot, as much as it tries, manage to deliver nuclear power (except in press releases). The Paris COP21 involves nations pledging to pursue supply side measures through renewable energy and to redouble demand conservation through energy efficiency. Those are the things that business can get along with. Nuclear power, at the fringes of developments now, only seems to get anywhere where the private sector is displaced by the state who ends up backing nuclear schemes which come very slowly at great cost.

I certainly don't claim to be  the leading theorist of ecological modernisation - there are a few I could name who are ahead of me on that - but amongst my writings on ecological modernisation I have written a book about  about ecological modernisation and renewable energy (see details on my profile). It is quite theoretical, I suppose, but the 'eco-modernist' manifesto seems to neglect some basic fundamentals of what ecological modernisation is about, according to the established literature. It seems to avoid engaging with serious thought and relies on what seems to me to be an arrogance of a disappearing mid-twentieth century industrial paradigm. I feel like I have been intellectually mugged and I am not at all surprised that the so-called eco-modernist manifesto crashed. That's because it is junk.

See the report in the Guardian on the 'launch'

http://www.theguardian.com/environment/2015/sep/30/ecomodernism-launch-was-a-screw-up-of-impressive-proportions
the so-called eco-modernist manifesto http://www.ecomodernism.org/ and one of its leaders:
http://blogs.new.spectator.co.uk/2014/10/owen-patersons-speech-on-abandoning-the-2050-climate-change-targets-full-text/

A few more words that I wrote during the course of a debate on this subject:
Contemporary Ecological Modernisation (EM) theorists like Mol and Janicke claim that they describe and analyse processes of ecological reform rather than make normative prescriptions. They argue that environmental objectives are defined through processes centrally involving environmental NGOs (especially emphasised by Hajer) and responses to consumers, but implemented by business. This excludes the so-called  'eco-modernist' project by definition since it leaves out, indeed excoriates, environmentalists and presumes what consumers want. 
I argue that In the case of renewable energy (see my Palgrave book and paper in Environmental Politics) this extends to identifying with renewable energy as a key solution; - with environmentalists helping make technological choices; in early stages as an active social movement, more recently as environmental groups in alliance with renewable industrial trade associations.
Nuclear power won't be a part of change precisely because it is not promoted by environmental groups or social movement organisations (however much the industry describes itself as 'green'). 
Although EM is implemented by business, in practice it can only do so in response to environmentalist/consumer preferences. This limits the extent to which it can be a purely top down process, and is one of the reasons why the recent claim of eco modernism being the way forward is misplaced.
NOTE: There are still some (used) copies of my book 'Ecological Modernisation and Renewable Energy' (Palgrave 2011) available from amazon for under or around �20!

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Payments to fossil fuel plant now being counted as 'environmental' by Treasury

In a move that will astonish many the Treasury have decided to count payments to existing fossil and nuclear power stations for providing capacity as 'environmental' levies'. Real environmental spending is, as a result of the Government's policies, falling, and is being replaced by payments for polluting power stations. This 'levy' money is collected as a levy on consumer energy bills. See the Table below complete with newly added budget line 'capacity market'.
The fear must be that as so-called environmental levies increasingly consist of payments to power stations to provide capacity, funding for renewables and energy efficiency will increasingly be crowded out by subsidies to fossil fuel power stations and nuclear power. Meanwhile spending on energy conservation has been slashed in this statement, and support for solar power and onshore wind cut to next to nothing in policy statements made earlier in the year. See some commentary on the latest cuts to energy efficiency spending at http://energydesk.greenpeace.org/2015/11/25/daily-dispatch-optimism-over-paris-tempered-by-calls-for-extra-money-for-worlds-poor/

The capacity mechanism has been introduced as a measure to encourage power station developers to bring new plant on line. You can see a description of the first auction at https://www.gov.uk/government/news/first-capacity-market-auction-guarantees-security-of-supply-at-low-cost
You can see comment by me on this at http://realfeed-intariffs.blogspot.co.uk/2015/10/government-heading-for-electricity.html and also in the context of Government plans energy plans at http://realfeed-intariffs.blogspot.co.uk/2015/11/amber-rudd-re-set-do-nothing-fantasy.html

So now we have a new policy - to extend a phrase used by the PM's office before the 2015 General election - 'cut the green crap'  - and spend it on brown crap instead! This is not a joke. The inclusion of the capacity mechanism under environmental levies is very serious indeed. This is because many believe that spending on the capacity mechanism will mushroom - and do so well beyond the figures mentioned in the Treasury below. The Government's policy is a very serious, perhaps mortal, blow for any UK programme to carry on reducing carbon emissions beyond 2020 or even 2018.
NOTE: I am corrected by Jon Ferris who points out that my original assertion (now deleted) that payments made through the capacity mechanism count towards the cap on low carbon spending is incorrect. Although the capacity mechanism is counted as being part of the 'levy Control Framework', The Government's energy statement, in 2014 at least, says that this is not included in caps on 'low carbon spending'. The extent to which this is a fine distinction may, in the light of the shifting emphasis of spending, be a matter of opinion! But I bow to John' in this case as a matter of form!
The Treasury figures........ 

2.7 Environmental levies
	� billion
	Outturn	Forecast
	2014-15	2015-16	2016-17	2017-18	2018-19	2019-20	2020-21
Carbon reduction commitment	0.6	0.7	0.7	0.5	0.5	0.5	0.5
Warm homes discount1	0.0	0.3	0.3	0.3	0.3	0.3	0.3
Feed-in tariffs1,2	0.0	1.3	1.5	1.7	1.9	2.1	2.2
Renewables obligation2	3.1	3.9	4.6	5.4	5.9	6.0	6.2
Contracts for difference	0.0	0.0	0.2	0.5	1.1	2.2	2.8
Capacity market	0.0	0.0	0.0	0.0	0.6	1.0	1.1
Environmental levies	3.6	6.2	7.3	8.5	10.3	12.2	13.1
Note: This is consistent with the 'Environmental levies' line in Table 4.6 of the November 2015 Economic and fiscal outlook.
1 The ONS have yet to include Warm Homes Discount and Feed-in Tariffs in their outturn numbers.
2 Forecasts do not include the outcomes of the consulatations on feed-in-tariffs or renewables obligation that have yet to be decided.

source:

Chart 2.7, Economic and fiscal outlook supplementary fiscal tables � November 2015, http://budgetresponsibility.org.uk/economic-fiscal-outlook-november-2015/

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Amber Rudd re-set: a do-nothing fantasy policy

Amber Rudd today compounded the fantasy that surrounds UK energy policy by declaring that the future would depend on new gas fired and nuclear power stations without any realistic policies of delivering such objectives. Meanwhile her Government is stopping support for renewable energy and energy efficiency even though (or perhaps precisely because) they are being delivered in substantial volumes.

New nuclear power, as discussed in previous blog posts are very unlikely to be deployed for the forseeable future, perhaps never. On the other hand the Government's capacity mechanism will serve, at best, to be a very expensive way of delivering gas fired power stations.

Nuclear Power - Hinkley C, as discussed earlier, seems only likely to be built in the context of the break up and bankruptcy of the French nuclear sector and EDF in particular  (see earlier posts) which hardly makes this likely. The other supposed nuclear projects have no realistic chances of investors given the high risk that surrounds the costs of such projects. See my earlier post http://realfeed-intariffs.blogspot.co.uk/2015/10/could-hinkley-c-spell-end-of-edf.html

Gas fired power stations - As discussed in an earlier blog post, no new gas fired power plant are currently set to be delivered. The capacity mechanism will 'spike' in its prices for new capacity in 2019 as the market is prepared for coal fired power stations to be finally phased out in 2023, that is if the Government do phase them out. See http://realfeed-intariffs.blogspot.co.uk/2015/10/government-heading-for-electricity.html
The capacity mechanism will prove to be a very expensive way of funding new combined cycle generating (CCGT) plant, none of which are likely to be deployed as a result of the first auction earlier this year.

The most cost-effective way of making CCGTs happen would be to organise auctions for contracts to be issued to them them broadly similar to that organised for renewable energy last year - what are called contract for difference (CfD) contracts to ensure that the power station operators got some certainty about electricity sales. But, they are unlikely to do this because then people would ask why contracts for the same price were not issued to onshore wind - which is a no-no for Tory Party political reasons.

An even better way to get more power plant capacity, as suggested also is the blog post about spiking capacity mechanism prices would be to incentivise lots of CHP plant and district heating which is the most flexible system available, as well as incentivising more energy efficiency to reduce demand.

A cheap way to provide new capacity is to incentivise the National Grid to install batteries and feed into them wind power which is otherwise constrained or worth zero on the wholesale market. That way wind can provide even more firm capacity than it does already (see last post on this). But that's far too imaginative for a Government who do not even realise that fracking and new nuclear power is just not going to happen.....


http://www.theguardian.com/environment/2015/nov/18/energy-policy-shift-climate-change-amber-rudd-backburner

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The untold story of how windfarms help keep the lights on

The UK press has been full of stories implying that wind power is to blame for the National Grid having to call in expensive demand shedding measures recently to keep the lights on. What they will not tell you is how often wind power saves the UK consumer large amounts of money because the National Grid does not have to buy in expensive reserves of power. Also they do not tell you that wind power in fact has quite a substantial contribution to effective firm power station capacity.

It is all very well repeating over and over again that the wind sometimes doesn't blow very strongly, but that doesn't tell you how to keep the lights on. Put simply, the chances of there being challenges to keeping enough electricity generation to meet demand at any point in time depends on a combination of factors being present; not just there being not much wind, but also that there are unexpected failures in power stations, unexpected high demand and unavailability of other power or demand side reduction options at any given time. Usually wind power will be slaving away saving the the need to buy in more reserves of power or demand side management during those winter days and nights when our electricity system is challenged. But we don't hear about this.

It would be as ludicrous to dismiss wind power's contribution to providing firm capacity as it would to insist that a particular power station can be guaranteed to be online all of the time. Indeed, a difference is that low wind power production may be usually more predictable than power stations going offline through breakdowns.

In fact, buried deep inside regulatory reports there is official recognition that wind power does have substantial equivalent firm capacity. As can be seen in OFGEM's electricity capacity assessments. See the 2014 version at https://www.ofgem.gov.uk/ofgem-publications/88523/electricitycapacityassessment2014-fullreportfinalforpublication.pdf

OFGEM defines:'Equivalent Firm Capacity of wind (EFC): the average contribution of wind power to the de-rated margin. It is the quantity of firm capacity (ie always available) required to replace the wind generation in the system to give the same level of security of supply' (pages 26-27)

In fact OFGEM's models indicate that the 'wind equivalent firm capacity factor'  varies in its models from 14.8 per cent to some 25.9 per cent depending on the scenarios modeled for a range of years.

Now that is quite substantial (ie a mean of around 20 per cent). According to the UKWED database there are currently around 13.5 GWe of wind power installed in the UK. http://www.renewableuk.com/en/renewable-energy/wind-energy/uk-wind-energy-database/

Hence, in effect, averaging out the mean of the models assessments of equivalent firm capacity provided by wind, wind power adds the equivalent of  2.7 GWe of firm capacity to UK generating capacity. That, by the way, is rather more than the equivalent of around two and a half Sizewell B nuclear power stations.

We hear a lot about how the Government is throwing huge sums of money into something called a capacity mechanism to produce very inefficient outcomes. What I'd like to see, (among a lot of other things!) is a calculation of how much the electricity consumer is saving through the equivalent firm capacity that wind power is providing, which is likely to be quite large! That, of course, is apart from providing a lot of cheap clean energy.

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Could Hinkley C spell the end of EDF?

EDF's apparent obsession with continuing with the increasingly financially toxic European Pressurised Reactor (EPR) programme by building another two units at Hinkley C could spell doom for EDF. Further drastic losses on Hinkley C similar to the mounting losses accrued by AREVA and EDF on the EPRs being built in Finland (Olikuoto) and France (Flamanville) might lead to what hitherto has seemed unthinkable - the break up of EDF. At least a major sell-off of assets seems almost certain if EDF is to finance Hinkley C, but if the project then went badly in the same way as the Olikuoto and Flamanville projects then both privatisation and a break up seem plausible outcomes.

Financial institutions are issuing increasingly strong warnings about the financial wellbeing of EDF, the electricity multinational which dominates the French electricity market. Both Moody's and Standard and Poor have issued warnings that EDF will face credit downgrades if it goes ahead with Hinkley C.  See http://www.thetimes.co.uk/tto/business/industries/utilities/article4574734.ece

Investec , an investment broker has urged people to consider selling shares in EDF (87 per cent of EDF is owned by the state, but 13 per cent is privately owned). The financial bulletin 'This Is Money' which has previously been very positive about the UK nuclear power programme reported this outcome and also commented: 'Future nuclear decommissioning costs in France are already set to affect EDF adversely and the bank questions whether the company has set aside enough cash to cope with this and the expense of refurbishing existing N-plants'
http://www.thisismoney.co.uk/money/news/article-3287956/Investment-bank-Investec-advises-clients-sell-shares-EDF-amid-fears-connection-nuclear-plant-Hinkley-Point-C-payouts-shareholders-threat.html. See also http://www.theguardian.com/business/2015/oct/22/broker-tells-investors-sell-edf-shares-hinkley-point-costs

The Financial Times recently reported that EDF 'looks to sell 10 billion euros worth of assets to boost balance sheet'  http://www.ft.com/cms/s/0/fcd6a462-7578-11e5-a95a-27d368e1ddf7.html#axzz3pTYWk2yt. EDF needs infusions of capital to meet the costs of the forced merger with the failing nuclear constructors AREVA, as well as its other liabilities, even before the Hinkley C 'investment' is considered. I put the word investment in quotes since there is increasing feeling in the financial community that a decision to go ahead with Hinkley C would be a huge financial risk. I would call it sheer madness. The EPR has already sunk AREVA. EDF, its nuclear client, has been drafted in to pick up the pieces. But if EDF has to absorb more EPR losses, next time there will not be a cousin company to pick up the damage. Could privatisation of EDF be a plausible outcome?

Indeed, the notion of privatisation as a general measure to reduce the debts of the French state have been discussed by Nick Butler of the FT, himself a regular sceptic about the plans for Hinkley C.
See 'Is privatisation the answer?'  http://m.ft.com/nick-butler/2014/10/12/is-privatisation-the-answer-for-france

Of course the notion of privatisation is barely on the agenda in France, and in the case of EDF it would be fiercely opposed by the left wing union, the CGT, which is very influential within and around EDF. But if EDF does go ahead with Hinkley C and the project ends up anything like as badly as the other EPR projects then EDF will be facing some very big losses indeed. Selling off more shares in the company may not be a good solution if the share price has fallen.

The French state could then be left with two options. First would be giving the bill to ordinary French people through a direct subvention of taxpayers money for EDF or an increase in electricity prices (maybe a mixture of the two) or, secondly, and here is the rub, breaking up EDF and selling off the still profitable parts to pay off the debts. So which would French people prefer, paying for mounting losses out of their own pockets, or breaking up EDF?

Of course people assume when we hear that a 'final investment decision' is soon to be taken by EDF over Hinkley C (note: a final investment decision has been about to emerge for three years now!) people assume that EDF have learnt lessons from the previous two reactors and that next time will be different. Why do people thiunk they have learnt anything? If anything, things seems to be getting worse with the other two schemes, with construction times becoming ever longer. A better question would be to turn it around and ask. Isn't it likely that Hinkley C will be a another disaster? EDF say they are going to build two reactors at once at Hinkley C! To cap it all, people have no idea whether the reactors will actually work (very well)!

Clearly too much notice is taken of EDF's pronouncements on what happens with Hinkley C. Certainly I have never thought that this project was rational. But are EDF pursuing financial rationalities? They are certainly pursuing what looks like an increasingly outdated industrial ideology with a deeply held religous zeal that defies notions of financial rationalities.  And that (via Hinkley C) may well lead EDF into the abyss.

Of course, as noted in my previous blog post, the Hinkley project has not made any serious progress in two years. It is not expected to happen any time soon, as they say. But even the possibilities that this mad project might happen is making the financial community very wary about EDF.

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Hinkley C - no progress in two years

The only successful thing about the Hinkley C project is the management of the news to imply that there has been progress in the project. In fact there has been absolutely no progress, certainly not in the financial terms, and in many ways things have got worse. That is compared to two years ago when the UK Government's much criticised terms, for paying EDF �94 per MWh (2015 prices) for 35 years underpinned by a 60 per cent loan guarantee by the Treasury, were given state aid clearance by the EU Commission.

Two years ago it was being reported that Chinese companies were to take between a 30 an 40 per cent equity stake in Hinkley C. It was reported that a 'final investment decision' would be taken by April 2014 and the project would be completed by 2023.

Now we hear blazoned across the media the 'new' breakthrough of a deal between EDF and the Chinese nuclear companies whereby the Chinese will take a one third equity stake in the project. The story goes that a final investment decision will soon be made and the expected completion date is now 2025. So what has changed over the last two years? Well, not the signing of a contract between the British Government and EDF, that is for sure, since no such thing exists. All that has changed, in substance it seems, in 2 years, is that the suggested completion date has been put back by....wait for it....2 years!
If you don't believe me, read for example the latter sections of the article in New Civil Engineer of October 22nd 2013 at http://www.nce.co.uk/news/energy/french-and-chinese-set-to-dominate-hinkley-c/8654517.article
Of course we have so many announcements of an imminent final investment decision over the past three years that their value has now depreciated to vanishing point.

But while nothing of substance has changed on the status of the commercial terms, there has been a major deterioration in technical and financial context of the European Pressurised Reactor (EPR) programme. The reactors being built in Finland and France, which were already overshooting their delivery dates in 2013 are still not finished, and not expected to be finished for some time yet. Major safety flaws have been found in the reactor, which is currently being investigated by the French nuclear regulators.

AREVA, the French state owned nuclear constructor collapsed and is being absorbed into EDF. Incredibly EDF is now reported to be selling off several billion pounds of assets to absorb the consequential liabilities and to fund Hinkley C. Now why would the French state want to take the very high risk of another disastrous project at Hinkley C with the same EPR design and end up shelling out billions of pounds of euros in losses to build a nuclear power station for another country (UK)? I don't know. It sounds mad to me. It is certainly a terrible advert for state ownership of electricity companies. Moody's are warning of a credit ratings downgrade for EDF if they go ahead with Hinkley C.

My own guess is that the British Government is only keeping the PR for the project positive because it hopes to provide a smooth passage for other financial deals it is doing with China, and to preserve at least the appearance of keeping alive the British nuclear power programme.

Supporters of nuclear power like to be charitable and say that if only the Treasury lent the project low interest loans (without insurance,presumably,to make the taxpayer doubly liable!) then the project would get built relatively cheaply. Well, no it wouldn't. For one very simple reason. The Treasury would not know how much to lend. This is  because, despite all the figures bandied around in analyses by the EU Commission and many others, nobody has a good idea of how much the project will cost. The Treasury, to their favour, is not prepared to write EDF a blank cheque. Long may this remain so.

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One line or multiple lines . . . That is the question!

All of us have been taught that having a system with one line is �better� than having dedicated lines (one per server). Engineers are taught about this in almost every Operations Research course, in almost every University around the world. Indeed, Queuing Theory provides strong support for this �fact�. It can be �demonstrated� that the average wait time for customers in the one line setting is far less than the average wait time for customers in the dedicated multiple lines setting, ceteris paribus. ("all things being equal").

Well, I disagree. The average wait time in both configurations are almost identical. Therefore, when setting aside �customer care� considerations (in particular �fairness�) there is no technical reason to choose one configuration over the other. And I will demonstrate it!

First of all, models traditionally used in Operational Research are based on very unrealistic assumptions, namely Poisson arrival processes and exponentially distributed service times (usually called the M/M/c model, where c stands for the number of servers). During my whole engineering career, I have never fitted an exponential distribution to processing times. The real world does not behave like that!

So, let�s assume for a moment that we do have a system that acts as that beautiful and neat �chalkboard� M/M/c model. Let's use the splitting property of the Poisson distribution to divide the problem in identical M/M/1 sub-models (1 server). The arrival rate for the sub-systems are identical and equivalent to 1/c the arrival rate that the whole system faces. So, using traditional Queuing Theory formulas, it could be demonstrated that the average wait time in the one line setting is indeed far less than the average wait time in each of the sub-systems.

We can verify this using a simple example. Let�s assume we have an M/M/4 system with an average arrival rate of 11.5 customers per hour and average service rate of three customers per hour in each server. Using the Sakasegawa*approximation for M/M/4 we can calculate the average wait time for this one line system as follows:

Now, using the splitting property of the Poisson distribution, we can elegantly assume that the arrival rate for each of the four M/M/1 sub-systems is 2.875 customers per hour (11.5 arrivals multiplied by 0.25, assuming equal probabilities for each of the four Poisson sub-streams). Now using the same Sakasegawa*approximation for M/M/1 (c=1) we get:

 In other words, this stylish and neat theory seems to support the assertion that the average wait time in the one queue system is less than the average wait time in the same system with multiple dedicated queues. Similar kind of �demonstrations� can be found in dozens, maybe hundreds of Operations Research text books around the world. Well, this is too good to be true. Something smells �fishy� here!

To validate the results, I prepared three separate models and simulated the same M/M/4 system in ExtendSim (� Imagine That Inc). The models are:

1. One line,
2. Four lines with one fourth of the arrival rate each (equivalent to four independent M/M/1 sub-systems), and
3. Four lines where customers select the shortest line after arriving to the system (�Intelligent behaviour� model).

The following figure shows the three models and the average wait times after a simulation time of 100,000 hours:

These are the results for the average wait time:

• One line: 1.86 hours.
• Four lines with one fourth of the arrival rate in each of the M/M/1 sub-systems: 7.43 hours.
• Four lines where customers select the shortest line (�Intelligent behaviour�): 2.15 hours.

In spite of its elegance, the neat mathematical assumption of having one 1/c of the arrivals assigned with equal probability to each of the individual lines (the splitting property of the Poisson distribution used in Queuing Theory) virtually never occur in real world situations. When having multiple lines, people and jobs are directed almost always to the shorter line (�Intelligent Behaviour�). So, myth busted!

The statement �The average wait time for customers in the one line setting is far smaller than the average wait time for customers in the dedicated multiple lines setting, ceteris paribus� is not applicable to most real world situations. As proven using computer simulation, there is almost no difference in wait times between the two configurations (1.86 hours for the one line configuration and 2.15 hours for the four lines with intelligent behaviour ). Therefore, the only reason some organizations prefer one line instead of dedicated lines is �fairness�.

If on top of all this, we have to remember that service times never distribute exponential in the real world. Therefore we can affirm that this neat Queuing Theory model is not the best option to deal with real world problems. I hope that after reading this article, professionals of the XXI Century will realize that computer simulation is the right tool to analyze queuing systems in the real world.

In the movie �The Imitation game� the Alan Turin character says �What if only a machine can defeat another machine?� I would like to adapt this question and say: �What if the complexity of the real world can only be analyzed using computer simulation?�

* Whitt, W, 1993, Approximating the GI/G/m queue, Production and Operations Management 2(2): 114-161.

Rene Alvarez, IE, MEng
www.SmartSimulation.ca

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