Power failure

from Wikipedia, the free encyclopedia
Short circuit (earth fault with tree) in an overhead power line

Under a power failure (including English blackout ) refers to an inadvertent interruption in the supply of electricity .

Duration of power outages ( SAIDI value ) in an international comparison (as of 2014).


Classification according to the cause

A power failure can be caused by faults in the power grid, in switching elements of the grid and in electrical systems, or by an imbalance between generation and consumption. A defect in an individual device or its supply line does not constitute a power failure.

According to the Low Voltage Connection Ordinance , the boundary between the power grid and the customer system is in the house connection box , which also houses the main fuses. Power failures in the area of ​​the customer system do not count as power failures according to the Energy Industry Act . The same applies to customers connected to higher voltage levels. Nevertheless, errors in the customer system can have the same effect as a power failure, especially in larger customer systems and if other customers are downstream in the customer system.

According to Section 52 of the Energy Industry Act, operators of energy supply networks must submit a report to the Federal Network Agency by April 30 of each year on all supply interruptions that have occurred in their network in the previous calendar year, including the measures taken to avoid future supply disruptions. The Federal Network Agency records faults lasting longer than three minutes with the following causes (figures for 2018):

  • Atmospheric agents: 6.262
  • Third party actions: 20,076
  • Force majeure: 2,584
  • Responsibility of the network operator: 36,262
  • Reaction disorders: 1,042
  • Other: 99,964
    This cause of malfunction includes all planned supply interruptions (except meter replacement).

The VDE | FNN compiles its own fault and availability statistics every year, which cover around 75% of the circuit lengths. From this the knowledge is derived that the medium voltage level has a decisive influence on the supply reliability. Since 2013, the FNN scheme for recording disruptions has been compared with that of the BNetzA.

A study by the Energietechnische Gesellschaft des VDE from 2006 revealed the following distribution of the causes of supply interruptions:

  • Medium voltage networks: 84%
  • Low voltage networks: 14%
  • 110 kV networks: 2%
  • Transmission networks 220/380 kV: 0.1%
  • Generation: 0%

Triggering of protective devices

  • Triggering the fuse ("blowing out" the fuse) or the circuit breaker of a circuit (rarely several) or the residual current circuit breaker (RCD, often switched three-phase, which separates many circuits) is a frequent cause of power failure in individual areas of a customer system , e.g. B. in one or more rooms or a device group.
  • If the main fuse blows , the entire house is affected by a power failure.

Atmospheric disturbances and storm damage

  • Lightning strikes (direct strikes) in conductor ropes or substations, but also strikes in the vicinity of lines cause overvoltages in the lines. As protection, overhead lines from the 110 kV level are spanned with earth cables as lightning protection and substations and outdoor switchgear are equipped with interception rods.
  • In a storm, branches or trees can fall onto the conductors and cause short circuits or earth faults. In such cases, an automatic restart is first used to check whether the arc fault has already eliminated the fault (burned away). The line is only completely switched off if the error persists.
  • Power poles can be knocked down by storms.
  • Extreme weather conditions, snow and ice such as in the Münsterland snow chaos or in 1998 in the Québec region in Canada. To remedy this, additional devices such as the Lévis de-icer can be installed for de-icing overhead lines if the self-heating of the overhead lines is no longer sufficient in extreme weather conditions in winter.
  • A magnetic storm led to a one-hour power failure in Malmö in 2003. A strong magnetic storm like the solar storm of 1859 could trigger a nationwide power outage.

Excavator damage

Underground cables are well protected underground. They are at risk during construction work. Improper work can lead to excavators grabbing and destroying the cable. Line information must therefore be obtained before civil engineering work. To protect underground cables from damage, alignment tapes are laid above the cables. The repair of damage to cables is more complex than to overhead lines. Power failures on underground cables are rare without outside interference, as damage to the insulation - especially in the medium and high voltage range - is detected during regular checks by means of partial discharge measurement before it leads to a failure.

Overload of a network element

If individual network elements are overloaded, they are switched off by protective devices. The main reason for this lies in exceeding the maximum permissible currents. The temperature of network elements can also be the cause of an overload. The failure of network elements is particularly critical in the case of power supply networks with a radial structure , since this is associated with direct and large-scale power failures in the downstream network areas. In order to prevent such failures, the (n-1) rule is applied in the area of ​​power grids, substations or power plants in order to maintain the overall operation of the power supply network in the event of failure or disconnection of equipment such as a power transformer, generator or overhead line.

Imbalance in the energy system

Electric current has virtually the same for consumption generated are transported to the points of consumption. Generation and consumption must correspond very precisely. An unexpected power shutdown may therefore from a (sudden) imbalance provided and requested power, for example, by the interruption of a circuit of large capacity (sudden loss of load) or the unannounced switching follow a large load (sudden overload).

The generation of electricity is generally regulated via the frequency: If consumption increases (i.e. the "load"), the power plant generators are more difficult to turn and their speed drops slightly, which means that the grid frequency falls below 50 Hz. The power plant output is then increased until the generators can supply 50 Hz again despite the higher load. As consumption decreases, the generators are easier to turn and their speed increases, causing the frequency to rise above 50 Hz. The power plant output must then be reduced so that the generators turn more slowly again. Generators in power plants are usually synchronous machines . With these generators, the speed is synchronous with the mains frequency. In the case of steam or gas turbines, the nominal speed corresponding to the nominal frequency of 50 Hz is usually 3000 min −1 . In the case of generators in hydropower plants, the nominal speed is often lower, with an integer fraction of 3000 min −1 corresponding to the number of pole pairs .

If the speed cannot be changed quickly enough in the event of a sudden, strong change in load, some of the consumers must instead be "disconnected" in the event of an overload. This is a load shedding . Switching off consumers is only a last resort. Previously, pantographs that have contractually agreed to do so and receive a fee in accordance with the ordinance on interruptible loads for the provision of this positive control power are switched off . Such current collectors can be aluminum smelters or steel works with large electric furnaces, for example. In the event of a sudden drop in load, loads can also be switched on (e.g. power-to-heat systems), which is then the provision of negative control power.

Sabotage and the effects of war

  • Targeted sabotaging attacks against power plants, redistributors or electricity pylons, for example on the night of fire in 1961 in South Tyrol, can lead to supra-regional power outages.
  • The US military first successfully used graphite bombs against the substations in Iraq in 1990/91 in the second Gulf War . Within a short period of time, 85% of Iraq's electricity supply was paralyzed.
  • At the 36th Chaos Communication Congress from December 27 to 30, 2019, Kaspersky showed in a 45-minute presentation how easy it would be for cyber criminals to take over the control center of a large German power plant, with the result that the power plant could be shut down so that at least one regional power supply could collapse.

Classification according to duration

  • Short-term failures in the time range of a few fractions of a second are colloquially referred to as power wipers , in which the energy supply is automatically restored after this short time. Causes at the distribution level can be short-term events such as lightning strikes, earth faults , arcing faults on overhead lines or, in rare cases, switching errors in switchgear or substations . Uninterruptible power supplies and emergency power generators should be able to react quickly enough to these short-term failures so that there is no permanent disruption to the system. Typical response times are between 15 and 50 ms.
  • Short-term voltage drop ( voltage dip ) as a result of overload due to unforeseen events. This condition is also known as brownout - named after the strong attenuation of incandescent lamp lighting - or sag and occurs in particular in smaller or undersized power grids with insufficient control power . As a rule, there is no serious damage. However, electronic devices react very differently to a brownout: Some devices have no adverse effects whatsoever, while other devices respond more sensitively to a brief voltage drop. For example, a lack of battery storage can lead to a loss of data or functionality. A so-called brownout detector can prevent such a scenario. Brownouts are relatively common, for example, in the Japanese power supply network, also due to the mixed network frequency of 50 Hz and 60 Hz, while national brownouts occur only very rarely in the European network system . Brownouts can also precede a catastrophic failure as a harbinger.
  • Medium or long-term power failure or total failure, which can range from a complete power failure in the minutes to several hours. This failure is also known as a blackout . Comparatively very long downtimes ranging from days to a few weeks are associated with extensive damage to the infrastructure such as the lines, for example as a result of extreme weather events in winter (see list of historic power outages , Münsterland snow chaos November 2005 ).

Classification according to spatial extent

An exact definition of the spatial extent of power outages does not exist. In general, however, a distinction is made between local or regional and supra-regional power failures.

Local and regional power outages

  • In the event of a defect in the low-voltage network (230/400 V), individual streets, settlements or - in rural areas - limited areas are disconnected from the electricity network .
  • Individual districts (districts) or, in rural regions, entire localities can fail if there are interruptions in the so-called medium - voltage network .
  • Is a larger (industrial) plant, e.g. B. a factory, affected by a failure of the connection to the external power grid, this is referred to as black case , English station blackout (SBO) . The blackfall can be caused by a failure of the power supply line, the power connection or the control of the system or by a failure of the higher-level power grid.

Supraregional power outages

  • Network-wide, supraregional power outages occur, for example, when large parts of the transmission network or the 110 kV network fail.
  • The most frequent cause is the disregard of the N-1 criterion , which states that the failure of a certain piece of equipment such as a line, transformer or generator must never lead to a total failure. Another cause can be direct multiple errors - however, these errors are rather rare due to the high level of automation.
  • Another cause is if the control of the network does not react or does not react quickly enough to disturbances or changes in the electricity network.

If the power supply in a network has completely collapsed and even the power plants can no longer draw electricity from the network, one speaks of a blackfall . In this case, only power plants capable of black start, such as specially prepared gas turbine power plants or river power plants without external energy supply, can start. The output of those black-start-capable power plants is then used to start non-black-start-capable power plants such as coal-fired power plants in stages. For safety reasons, some non-black start-capable power plants, such as nuclear power plants , also have their own black-start capable units, mostly in the form of gas turbines, with which the power plant can be self-sufficient and the power plant can be started without an external energy supply.

Major power failure scenario

Power supply companies usually cite a defect in a power plant , damage to a line , a short circuit or a local overload of the power grid as reasons for a power failure in an entire area . However, these occasions would generally not be a reason for a power outage if the regulation was functioning. Supraregional power grids are operated according to the (n − 1) criterion . This means that electrical equipment, a transformer, a line or a power plant can fail at any time without overloading other equipment or even interrupting the energy supply. The integrated networks in Germany and in the UCTE area must be managed according to this standard . Does it come, however - z. B. due to a defect in a power plant - the simultaneous failure of several transformers or lines can lead to an interruption of the power supply. In a correctly operated system, at least two events must come together so that an interruption in supply can occur.

The (n-1) criterion valid in transmission network operation was originally developed for systems with local network coverage and short transport distances. This criterion has proven to be inadequate against large-scale and supra-regional network failures (blackouts), the frequency and extent of which are increasing worldwide. In the decades between 1965 and 1995, large-scale network failures still occurred sporadically; after 2005 there were an average of 14 events per year. They have their reasons in multiple failures and / or cascading errors in the network and may be. a. attributed to the high utilization of the transmission network (which leads to restrictions in network renewals, network reinforcements and expansions), the inconsistent feed-in from renewable energy sources and the vulnerability of large transmission routes from the generator to the consumer. The shutdown of the 7 + 1 nuclear power plants in March 2011 exacerbated this situation due to the loss of power in southern Germany.

The investigations into the causes of the blackouts that have occurred around the world show that the main cause complexes are: privatization and liberalization led to the neglect of the networks and their infrastructures; the increased growth of renewable energy causes the instability of the grid.


If not enough energy can be activated for the current demand in one's own network, e.g. B. If the grid control fails, the grid frequency in particular drops , because the load difference is initially covered by the kinetic energy of all rotating masses in the generators. This case is known as underfrequency and is divided into five levels in the Western European network (UCTE control area): In addition to the short-term activation of reserves, in particular automatic load shedding is carried out.

If stabilization cannot be achieved as a result, the last consequence is a separation into several, mutually asynchronous network areas, between which no more power flow occurs. This leads to total failures in individual network areas as the power plants are automatically disconnected from the network. Larger caloric power plants (base load power plants) such as coal-fired power plants or nuclear power plants try to cope with their own needs when the grid is disconnected by reducing the output and to maintain this non-optimal operating state for a few hours. If this catching and holding in the power plant's own consumption does not succeed, the affected power plant units are switched off, which leads to a longer process of recommissioning.


The network connections are switched to different locally separated substations so that if one substation fails, the other can continue to be supplied with power. The higher-level network is usually the same for both substations, so that a fault there also affects both connections. Much more important is z. B. the use of an uninterruptible power supply system (UPS) in hospitals .

In the IT area , power failures can lead to the loss of unsecured data and, in individual cases, damage to devices. In the event of a power failure, individual devices can still send messages to other devices, e.g. B. a dying gasp signal .

Serious economic damage can also occur in industrial companies that are dependent on a continuous supply of energy and cannot easily continue a production process after a service interruption (e.g. the chemical industry, food processing, etc.).

In the private sector, too, longer power failures can have unpleasant consequences:

  • Lighting: electric light, traffic lights, signals
  • News: radio and television sets with mains voltage; Batteries run out quickly. Many transmission systems have emergency power generators.
  • Communication: Mobile telephony is only available for a limited time in the event of a longer power failure, as cell phone masts usually only bridge a few hours with the help of batteries; Fixed line and internet are i. A. depending on (currentless) end customer routers.
  • Security: Door intercom systems and door openers, access security systems, alarm systems, fire alarms and warning lights for air traffic on tall structures only work if and as long as batteries or emergency power systems are used as a replacement. Hospitals in this country have emergency power generators and particularly critical areas such as operating theaters and intensive care medicine have an uninterruptible power supply . Escape route marking lights in larger (residential) buildings are usually individually battery-powered and light up for a while.
  • Mobility: elevators, cable cars, parking garage gates; Some railways have their own power supply networks.
  • Water: Drinking water treatment and sewage disposal with pumps fail after a while. In the case of water supply networks that are operated by the natural gradient and without pumps (such as the Viennese water supply via the high spring water pipes), a power failure has little effect on the supply.
  • Fuel: filling stations usually do not have an emergency generator or connection for it; the dispenser pumps fail.
  • Heat: air conditioning, ventilation, electric heating; But even oil, gas and pellet central heating systems have no control, no ignition spark and no circulation pump without electricity.
  • Money: Bank ATMs are mostly inoperative.
  • Shopping: Supermarkets close, as cash registers and main lighting often fail, as do restaurants. Electric sliding and revolving doors are inoperable.
  • Food: Fridge and freezer contents can thaw / spoil in the event of an extended power failure.

A study by the Office for Technology Assessment at the German Bundestag (TAB) comes to the conclusion that a long-term, large-scale power failure would affect all critical infrastructures and a collapse of society as a whole could hardly be prevented. Despite this potential for danger and catastrophe, social risk awareness in this regard is only rudimentary.

Emergency power operation

Power failures are particularly critical for hospitals , as they need power to operate medical devices. But also safety-relevant systems (such as radar devices for air traffic control , traffic lights or signal systems for railways ) or other suppliers (such as waterworks , gasworks or telecommunications companies ) require electricity to work. For this reason, hospitals and other critical facilities, like many companies, have emergency power generators that are often operated with diesel generators and switch on automatically as soon as a power failure occurs ( general backup power supply ). In addition, many facilities have several network connections to (largely) independent networks.

The period of time that can be bridged in emergency power operation differs greatly. The public broadcasting should remain able to transmit at least 3 days to inform the population - the Rundfunk Berlin-Brandenburg there are, for example, 8 days, but on only one radio wave instead of the normal operation of six frequencies.


The central telecommunication facilities and main exchanges are consistently prepared for longer emergency power operation. The local exchanges, which can supply the end devices with electricity with copper cables, are usually only designed with buffer batteries for 4 hours. In the event of a long-term failure, only a few terminals and in particular public telephone booths will continue to be operated there. The cellular networks work with emergency batteries in the event of a power failure. In this way, continued operation for about a day can be ensured, but only on a greatly reduced number of channels. A battery backup of at least 12 hours is provided for the BOS radio , which ensures the complete operation of all end devices; thereafter, there may also be a restriction in the employability.

Economic costs

A large part of the consequences includes the fact that parts of the added value in the affected economy are lost for a certain period of time. Economics Minister Philipp Rösler said in May 2011: “In studies, the amount of damage caused by a blackout is at least 6.50 euros per kilowatt hour. We use around 1.6 billion kilowatt hours a day. The daily gross domestic product in Germany is around 6 billion euros. If the electricity went out for a day in all of Germany and nothing could be produced anymore, that would be considerable damage. There are also indirect costs. "

A study by the Technical University of Berlin from 2011 estimates these economic costs at a weighted average of at least 8.50 euros / kWh. The costs of the individual consumer groups are estimated at at least the following values:

Agriculture Industry Services Public administration households
2.34 EUR / kWh 2.49 EUR / kWh 16.35 EUR / kWh 5.53 EUR / kWh 15.70 EUR / kWh

Strictly speaking, all the figures are hypothetical, since the actual damage apart from the inability to provide services can hardly be estimated. The Hamburg World Economic Institute (HWWI) came to the conclusion in 2013:

  • There is a growing potential for risk.
  • The study is deliberately limited to power outages of no more than one hour.
  • Costs that are difficult to estimate in the event of longer downtimes, such as the interruption of the supply chain or the failure of cooling systems, are thus excluded from the analysis.

The blackout simulator, with which a cost simulation (unavailability of services) can be carried out, comes from an Austrian and subsequently European research project. However, no damage resulting from a blackout can be taken into account here.

Power failure in nuclear power plants ("blackfall")

To hedge against external network failures, the nuclear power plants (NPP) in Germany must have at least two network-side supply options according to the nuclear rule " KTA 3701" and - in the event of failure of the external networks - an automatic switchover to the power plant's own demand (load shedding to own demand). Only if these three feed routes fail does the emergency power case occur, which is safeguarded by the redundant emergency power system of the power plant, which covers the power requirement for the redundant after-cooling pumps for residual heat removal . The emergency power case is an explicit investigation case in the “ Probabilistic Safety Analyzes (PSA)” of the NPP (“triggering accident”) and is given with a frequency of H = 2.5% per year.

On several occasions, however, NPPs have already struggled with problems relating to the proper functioning of these emergency power generators and their connection devices. Best known in this regard are probably the Fukushima nuclear accidents and the 2006 accidents at the Forsmark nuclear power plant in Sweden . Similar incidents occurred in 1975 in the Greifswald nuclear power plant , 1982 in the Belgian nuclear power plant Doel , 1999 in the French nuclear power plant Blayais , 2000 in the New York nuclear power plant Indian Point  2, 2001 in the Taiwanese nuclear power plant Maanshan , 2004 in the nuclear power plant Biblis , 2007 in the French nuclear power plant Dampierre and nuclear power plant Penly and Swiss nuclear power plant Beznau 1 and 2011 in the French nuclear power plant Tricastin .

On April 26, 1986, the operators of the Chernobyl nuclear power plant practiced mastering a nuclear reactor ( Block 4 ) in the event of a complete power failure. Due to serious violations of the applicable safety regulations and the design-related properties of the graphite-moderated nuclear reactor, there was an uncontrolled increase in power, which led to the reactor fire and explosion ( Chernobyl disaster ).

Reliability of the power supply in the Federal Republic of Germany

Downtime in different countries

In its availability statistics for 2014, the Federal Network Agency (BNetzA) determined that the unavailability of electrical energy was 12 minutes and 28 seconds, which was the lowest value since the systematic measurements began. In 2013 the value was over 15 minutes, in 2008 it was 16.89 minutes

In 2006 it was over 20 minutes. Although it is often feared, the energy transition and the decentralized feed-in of renewable energies will continue to have no negative effects on the security of supply for end consumers. With an average unavailability of electricity of 15.91 minutes for end consumers, Germany was the country with the highest security of supply in 2012 .

Power failures in the traction current network and in the public network almost never have reciprocal effects because both systems are operated largely independently of one another, partly because of different network frequencies. With the SAIDI (System Average Interruption Duration Index) an internationally recognized statement about the quality of the power grid can be made.

SAIDI values ​​for Germany 2006–2012

The reliability of the interconnected network is determined today - as experience from past network failure events show - by the risk of multiple errors (cascading errors) in the network. The system index (SAIDI) does not provide any information about this.

General data Low voltage Medium voltage SAIDI
Reporting year Number of network operators / networks End consumers (in millions) Number of interruptions (in total in thousands) SAIDI (minutes) Number of interruptions (in total in thousands) SAIDI (minutes) SAIDI (minutes) Unavailability in%
2018 866/872 50.7 143.7 2.34 23.7 11.57 13.91 0.0026%
2017 862/869 50.5 143.0 2.22 23.5 12.92 15.14 0.0029%
2016 860/868 50.3 148.3 2.10 24.3 10.70 12.80 0.0024%
2015 850/860 49.9 150.9 2.25 26.7 10.45 12.70 0.0024%
2014 874/884 49.6 147.8 2.19 26.0 10.09 12.28 0.0023%
2013 868/878 49.5 151.4 2.47 27.8 12.85 15.32 0.0029%
2012 866/883 49.3 159.0 2.57 32.0 13.35 15.91 0.0030%
2011 864/928 48.9 172.0 2.63 34.7 12.68 15.31 0.0029%
2010 890/963 49.0 169.2 2.80 37.1 12.10 14.90 0.0028%
2009 821/842 48.4 163.9 2.63 35.1 12.00 14.63 0.0028%
2008 813/834 48.4 171.5 2.57 36.6 14.32 16.89 0.0032%
2007 825 48.5 196.3 2.75 39.5 16.50 19.25 0.0037%
2006 781 48.5 193.6 2.86 34.4 18.67 21.53 0.0041%

Data: Federal Network Agency

Power failure in the media

The novel Blackout - Tomorrow is too late by Marc Elsberg describes the effects of a large-scale power outage in Europe over two weeks.

See also

Web links

Wiktionary: power failure  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ↑ The risk of power failure increases - causes for a power failure
  2. Individual fault data of the reported interruptions in supply in 2018 (xlsx, 10 MB) Federal Network Agency, accessed on October 23, 2019 .
  3. ↑ Reliability of supply - the FNN fault statistics. VDE, accessed on October 22, 2019 .
  4. Malfunction and availability statistics, reporting year 2016. VDE, October 25, 2017, accessed on October 22, 2019 .
  5. Malfunction and availability statistics - Instructions - Systematic recording of malfunctions and supply interruptions in electrical energy supply networks and their statistical evaluation. VDE FNN, December 2016, accessed on October 24, 2019 .
  6. Energietechnische Gesellschaft im VDE (ETG): Quality of supply in the German power supply network . VDE analysis, Frankfurt, February 1, 2006
  7. Halloween Space Weather Storms of 2003. ( April 1, 2014 memento in the Internet Archive ) NOAA Technical Memorandum OAR SEC-88, Space Environment Center, Boulder, Colorado, June 2004, p. 37, accessed December 17, 2013.
  8. How dangerous are coronal mass ejections? A look back at the Carrington event of 1859
  9. Stefan Loubichi: 36C3 - more open questions than answers. VGB PowerTech Journal, issue 1–2 / 2020, ISSN 1435-3199
  10. What is a brownout? In: www.next-kraftwerke.de. Retrieved July 20, 2016 .
  11. US legal definition "station blackout"
  12. a b Effects of the nuclear power plant moratorium on the transmission grids and security of supply. ( Memento from April 23, 2013 in the Internet Archive ) Report from the Federal Network Agency to the Federal Ministry of Economics and Technology, April 11, 2011.
  13. ^ A b Marko Čepin (University of Ljubljana): Assessment of Power System Reliability: Methods and Applications , Springer, 2011.
  14. a b Power Blackout Risks - Risk Management Options - Emerging Risk Initiative (PDF; 2.0 MB)
  15. Power failure: precaution and self-help. ( Memento of the original from March 4, 2016 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF) Flyer of the BBK - Federal Office for Civil Protection and Disaster Relief @1@ 2Template: Webachiv / IABot / www.bbk.bund.de
  16. Th. Petermann u. a .: What happens in the event of a blackout. Consequences of a long and large-scale power outage. (= Studies by the Office for Technology Assessment at the German Bundestag. 33). edition sigma, Berlin 2011, ISBN 978-3-8360-8133-7 .
  17. New threats and risks. Security interests and protection of the population. Lecture on March 19, 2009 on the occasion of the 11th DRK Rescue Congress.
  18. Non-public land radio service of the authorities and organizations with security tasks (BOS): Implementation of the BOS radio guidelines at the non-police BOS. Bavarian State Ministry of the Interior, December 2009.
  19. We should consider a cold reserve. ( Memento from September 16, 2011 in the Internet Archive ) Interview with Minister of Economics Rösler. May 28, 2011. In: FAZ.
  20. A. Praktiknjo, A. Haehnel, G. Erdmann: Assessing energy supply security: Outage cost in private house holds. In: Energy Policy. Vol. 39, No. 12, December 2011, pp. 7825-7833. doi: 10.1016 / j.enpol.2011.09.028
  21. Licht ins Dunkel: An estimate of the potential damage from power outages in Germany. In: HWWI Update. 9, 2013.
  22. ^ Blackout simulator
  23. KTA 3701: Superordinate requirements for the electrical energy supply in nuclear power plants. ( Memento of December 13, 2013 in the Internet Archive ) (PDF; 100 kB). April 2004.
  24. Assessment of the accident risk of advanced pressurized water reactors in Germany (PDF; 8.5 MB), GRS, GRS-175, Oct. 2002 (Section 5.1 Triggering events).
  25. Federal Network Agency : Continued high security of supply in German electricity networks (PDF)
  26. 12 minutes without electricity . In: Süddeutsche Zeitung . August 21, 2015. Accessed August 21, 2015.
  27. Federal Network Agency: Quality of the electricity supply in 2015 at a consistently high level. Press release from October 21, 2016. Quote: "The energy transition and the increasing proportion of decentralized generation capacity continue to have no negative effects on the quality of supply."
  28. Christoph Pieper u. a .: The economic use of power-to-heat systems in the balancing energy market. In: Chemical Engineer Technology . Volume 87, No. 4, 2015, 390-402, p. 390, doi: 10.1002 / cite.201400118 .
  29. Federal Network Agency: Key figures for electricity supply interruptions , accessed on April 5, 2018.