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In a nutshell
- What is the problem? A severe geomagnetic storm may have the potential to destroy power grids around much of the world.
- Who is already working on it? Power companies, insurance companies, and governments all have an interest in protecting the grid from geomagnetic storms. As far as we know, there is very little philanthropic involvement in this issue.
- What could a new philanthropist do? The grid can be protected through hardening and through the installation of ground-induced current blocking devices that would prevent the currents generated by a geomagnetic storm from flowing through the grid. A philanthropist could fund further research on the threat posed by geomagnetic storms or on mitigation possibilities, fund advocacy for dealing with the threat, or directly fund mitigation.
Published: January 2014
Published: January 2014
What is the problem?
Eruptions from the sun can disrupt the Earth’s magnetic field, potentially damaging power grids and satellites.1
In 1989, a geomagnetic storm caused blackouts and damaged equipment throughout Quebec, costing an estimated total of $6 billion.2 In 1859, a storm approximately three times more powerful that the 1989 storm occurred, though it caused no major damages because there was little electrical infrastructure at the time.3 A storm about 10 times as intense as the 1989 storm may have occurred in 1921.4
According to John Kappenman, a consultant who works on geomagnetic storms, a 1 in 100-200 years worst-case scenario geomagnetic storm could destroy large transformers throughout the world and cause a global power outage that would take years to fix.5 Other estimates appear to be substantially less aggressive: the North American Electric Reliability Corporation, a power industry group, reported that only older transformers would be likely to be damaged in a severe geomagnetic storm, and the US Department of Homeland Security noted that Kappenman was the only source of more extreme estimates of damages from geomagnetic storms.6 A 2011 report for the OECD concluded that the threat from geomagnetic storms is not well-understood.7
We do not feel that we have a good understanding of the degree of risk from geomagnetic storms, though we would guess, with low confidence, that Kappenman’s 1 in 100-200 year figure for a globally devastating storm is likely to overstate the degree of risk.
Besides the risk to the power grid, geomagnetic storms also threaten satellites and aviation.8 A high-altitude detonation of a single nuclear weapon, known as an electromagnetic pulse (EMP) attack, could cause similar effects as for a geomagnetic storm over an area the size of the continental US.9
Who is already working on it?
Power companies, state and federal governments, and insurance companies all have a stake in responding to geomagnetic storms:
- Power companies presumably want to protect their infrastructure from damage, though Kappenman argues that US power companies are not fully aware of the threat posed by geomagnetic storms.10 We have not investigated the extent to which power companies have responded to geomagnetic storm risks.
- Insurance companies might be able to pressure power companies to protect their assets from geomagnetic storms by promising lower premiums for those who take this step.11 Insurance companies appear to be considering how to incorporate geomagnetic storms into their risk models.12
- The US federal government has been concerned by the risk of electromagnetic pulse attack (which would cause similar damages and require similar mitigation strategies to a geomagnetic storm) since the Cold War, although its commitment to mitigating the damages from such an attack may have lessened since then.13
The SHIELD Act, which would require power companies to mitigate the threat from geomagnetic storms, has been introduced in the House but, as of July 2013, had not been voted on by either chamber.14
According to Kappenman, the US has done more about the threat from geomagnetic storms than other countries have.15
- The Federal Energy Regulatory Commission (FERC) is charged with enforcing geomagnetic storm-related regulations on the power industry. Our understanding is that FERC works with an industry group, the North American Electric Reliability Corporation (NERC) to devise standards, which FERC can then either accept or remand to NERC for revision. As of August 2013, NERC was working on new standards to mitigate the risk from geomagnetic storms that were to be made public in 1-2 years.16
- To our knowledge, Maine is the only state to have passed a law requiring power installations to be robust to EMPs and geomagnetic storms.17
A small number of advocates like Kappenman currently try to persuade NERC and the government to do more about the threat from geomagnetic storms, but as far as we know, there is very little philanthropic involvement in this issue.18
What could a new philanthropist do?
A philanthropist could potentially pursue a number of different approaches aiming to reduce risks from geomagnetic storms:19
- further research on the risks of geomagnetic storms and potential mitigation strategies
- advocacy for stronger geomagnetic safety standards for electric utilities, or for public funding to support mitigation efforts
- directly funding mitigation in partnership with electric utilities.
We do not have a strong sense of the likely returns to any of these strategies, though we would guess that the research and advocacy approaches would carry higher expected returns than direct support for mitigation.
Approaches to mitigating geomagnetic storm risk
The two basic options available to protect the grid are operational mitigation and hardening. Operational mitigation entails operating the grid in such a way as to reduce the threat from geomagnetic storms.20 The most radical kind of operational mitigation would be to unplug grid components in advance of a predicted geomagnetic storm so that they are not vulnerable to the effects of the storm. This strategy is feasible because satellites can predict periods of a few days when geomagnetic storms are likely.21 However, the national grid would likely have to be shut down for several days, which would cause enormous economic damages.22
Kappenman believes that for $1 billion, the US grid could be hardened to resist the effects of geomagnetic storms with ground-induced current (GIC) blockers.23 However, GIC blocking devices may turn out to be more expensive than Kappenman estimates, and a more diversified hardening strategy might be necessary to protect the grid.24
It is possible to undertake some operational mitigation and hardening for satellites, though both approaches face challenges.25
Questions for further investigation
Our research in this area has been very limited, and we have yet to answer many important questions.
Amongst other topics, our further research on this cause might address:
- How much attention do national governments (including the U.S.) pay to the threat of geomagnetic storms and EMP attack?
- How do power companies currently respond to the threat posed by geomagnetic storms?
- How likely is further research to pay off in better estimates of the likely damages from severe geomagnetic storms and in better mitigation strategies? Are better estimates already available from experts we did not contact?
- How significant is the risk of an EMP attack?
We initially decided to investigate geomagnetic storms because we thought that damages to the power grid from geomagnetic storms might be a serious risk that is relatively easy to quantify and interventions to mitigate the risk might be relatively tractable.
The investigation that went into this report has been very limited, consisting primarily of review of risk assessments by government agencies and other actors and a conversation with John Kappenman, the owner of Storm Analysis Consultants.
“The Sun is the source of severe space weather. Large, violent eruptions of plasma and magnetic fields from the Sun‘s corona, known as coronal mass ejections (CMEs), are the origin of geomagnetic storms (National Academy of Sciences [NAS], 2008). CME shock waves create solar energetic particles (SEPs), which are high-energy particles consisting of electrons and coronal and solar wind ions (mainly protons). When CMEs head towards the Earth, these geomagnetic storms create disturbances that affect the Earth‘s magnetic field. It takes approximately two to three days after a CME launches from the Sun for a geomagnetic storm to reach Earth and to affect the Earth‘s geomagnetic field (NERC, 1990).
Disturbances in the Earth‘s geomagnetic field can disrupt the operation of critical infrastructures relying on space-based assets but also can result in terrestrial effects, including disrupting electricity distribution networks.” CENTRA 2011, pg. 7.
“On 13 March 1989, a geomagnetic storm affected Canadian and U.S. power systems, resulting in a major power outage for nine hours for the majority of the Quebec region and for parts of the northeastern United States (Molinski et al., 2000). The Hydro-Quebec grid‘s geographic location and its 1,000 km transmission lines to the load center made it susceptible to geomagnetic storms (Kappenman and Albertson, 1990). Central and southern Sweden also experienced power losses when GICs disrupted six 130kV power lines (Babayev et al., 2007). The GICs flowing through the power system severely damaged seven static compensators on the La Grande network in the Hydro-Quebec grid, causing them to trip or shut down automatically before preventive measures were possible (NERC, 1990). The loss of the compensators resulted in a system disturbance and severe equipment damage. The unavailability of new equipment to replace the La Grande network‘s damaged equipment prevented power restoration to the transmission network. The power delay was also due to the damaged equipment and load transfers at the distribution network level. While work was being conducted to bring power back to the Hydro-Quebec grid, the New Brunswick and Ontario power systems helped provide emergency assistance to Quebec. As power was restored to Hydro-Quebec, it received assistance from New England and New York systems as well as the Alcan and McLaren systems based in Quebec. The voluntary reduction of power use by industrial customers during the incident also helped Quebec to meet its power demands.
After nine hours, 83 percent of full power was restored but one million customers were still without electrical power (NERC, 1990). The total cost of the Hydro-Quebec incidents is estimated to be $6 billion. (Canada/OCIPEP, 2002). Since the incident, the Canadian government has set up protective measures at the Hydro-Quebec site, such as transmission line series capacitors, which cost more than $1.2 billion, to block GICs from damaging the system (Canada/OCIPEP, 2002).” CENTRA 2011, pg. 13.
- “Molinski‘s definition of severe, however, is greater than 300 nT/min, below the severity of the March 1989 geomagnetic storm (480 nT/min) and more than an order of magnitude below the severity required for the consequences in the United States estimated by Kappenman in his 2007 analysis.” CENTRA 2011, pg. 18.
- “The Carrington Event of 1859 (described later in the report) was measured at -1760 nT (Lakhina et al., 2005).” CENTRA 2011, pg. 9.
- “While the socioeconomic impacts of a future Carrington event are difficult to predict, it is not unreasonable to assume that an event of such magnitude would lead to much deeper and more widespread socioeconomic disruptions than occurred in 1859, when modern electricity-based technology was still in its infancy.” Severe Space Weather Events 2008.
“Further anecdotal evidence suggests that a dBh/dt of about 5000 nT/min may have occurred during the Great Geomagnetic Storm of May 1921.” Kappenman 2006, pg. 198.
“Storms could be as much as ten times larger than the 1989 storm. Such a storm could wrap around the globe, causing large transformers to fail across the world. In a given year, there is a 1 in 100 to 1 in 200 chance of such an event. Although geomagnetic storms tend to be more intense near the poles, recent research suggests that the risk is global.
A large geomagnetic storm could result in a years-long global blackout. Large transformers destroyed by geomagnetic storms would have to be replaced to restore the function of the grid. Large generators might also be affected and have to be replaced. There are few extra transformers currently on hand. Under normal conditions, factories would take about four months to assemble one transformer. One factory could make 30-50 transformers per year. There are about 500 transformers in the US that might need to be replaced in the event of a large geomagnetic storm. Transformer and generator manufacturers depend on many services that would be interrupted by large-scale power outages. These include just-in-time delivery of materials from around the world, transportation, and access to a highly skilled work force. Nations are likely to impose restrictions on the export of raw materials as well as transformers. Given all of these factors, it could be years before the grid was restored. If the grid were down, there would only be limited potential to use alternative energy sources. Many people have natural gas generators at their homes to use in case of emergency, but the extraction and transportation of natural gas requires electric power from the grid. Oil and gasoline production requires power from the grid for extraction, refinement, and transportation. Wind and solar power are likely to remain usable, but they currently represent a very small portion of our infrastructure.” Notes from a conversation with John Kappenman, 8/6/2013.
- “NERC recognizes that other studies have indicated a severe GMD event would result in the failure of a large number of EHV transformers. The work of the GMD Task Force documented in this report does not support this result for reasons detailed in Chapter 5 (Power Transformers), and Chapter 8 (Power System Analysis). Instead, voltage instability is the far more likely result of a severe GMD storm, although older transformers of a certain design and transformers near the end of operational life could experience damage, which is also detailed in Chapter 5 (Power Transformers)…Voltage collapse can occur when there is insufficient reactive support in a wide area, leading to depressed voltages and eventually to blackout. The 2003 blackout experience shows that voltage collapse could result in blackout of hours in duration, but with minimal equipment damage” Geomagnetic Disturbance Task Force 2012, pg. vi.
- “Three of the recent, high-profile analyses used in this Issue Brief’s literature review all relied on a single source — John Kappenman — for estimates of consequence that tended to be more extreme than other perspectives.37 As an example, Kappenman testified before Congress that a severe geomagnetic storm would have catastrophic effects with infrastructure and economic impacts that could persist for multiple years and cost several trillion dollars per year; yet it was unclear what kind of analysis and methodology led to those impact assessments.” DHS Office of Risk Management and Analysis 2011, Pg. 10.
“The literature on geomagnetic storm risk assessments indicates that the state of the art for assessing the security risk from this type of event is still inchoate. There are examples of analyses that describe threat, vulnerability, and consequence, but they are not integrated, primarily because of the weakness in the threat analysis. The lack of valid risk assessments has limited risk mitigation efforts in many critical infrastructure sectors, as it is difficult to demonstrate the utility of investing in either hardening or operational mitigation efforts, especially if these investments reduce time and money spent in preparing for more common risks.” CENTRA 2011, pg. 6.
“The main industries whose operations can be adversely affected by extreme space weather are the electric power, spacecraft, aviation, and GPS-based positioning industries. The March 1989 blackout in Quebec and the forced outages of electric power equipment in the northeastern United States remain the classic example of the impact of a severe space weather event on the electric power industry. Several examples of the impact of space weather on the other industries are cited in the report:
- The outage in January 1994 of two Canadian telecommunications satellites during a period of enhanced energetic electron fluxes at geosynchronous orbit, disrupting communications services nationwide. The first satellite recovered in a few hours; recovery of the second satellite took 6 months and cost $50 million to $70 million.
- The diversion of 26 United Airlines flights to non-polar or less-than-optimum polar routes during several days of disturbed space weather in January 2005. The flights were diverted to avoid the risk of HF radio black- outs during PCA events. The increased flight time and extra landings and takeoffs required by such route changes increase fuel consumption and raise cost, while the delays disrupt connections to other flights.
- Disabling of the Federal Aviation Administration’s recently implemented GPS-based Wide Area Augmentation System (WAAS) for 30 hours during the severe space weather events of October-November 2003.” Severe Space Weather Events 2008, Pg. 2.
“High altitude EMP (HEMP) results from a nuclear detonation typically occurring 15 or more miles above the Earth’s surface. The extent of HEMP effects depends on several factors, including the altitude of the detonation, the weapon yield and design, and the electromagnetic shielding, or “hardening,” of assets. One high-altitude burst could blanket the entire continental United States and could cause widespread power outages and communications disruptions and possible damage to the electricity grid for weeks or longer.4 HEMP threat vectors can originate from a missile, such as a sea-launched ballistic missile; a satellite asset; or a relatively low-cost balloon-borne vehicle. A concern is the growing number of nation-states that in the past have sponsored terrorism and are now developing capabilities that could be used in a HEMP attack.” Wales 2012.
“Industry self-policing can be particularly indicted in the case of geomagnetic storms, in that the vulnerability of the infrastructure to this threat has steadily grown over decades to the proportions where it can now be legitimately called an “Unrecognized Systemic Risk”. This is a Risk which has remained unchecked, as there has never been a design code by the power industry to take into consideration this threat. Therefore power grid infrastructure operators, power system operators and planners have simply not appreciated the extent to which risk has migrated through their technical systems from this specific threat. This suggests a framework for solutions that must be focused on mandatory requirements; such as codes of design and, where needed, remedial corrections of the infrastructure with appropriate “force of law” oversight. Again numerous examples already exist on how these practices have been routinely adopted in areas where the interests of society need to be protected, such as fire codes, codes of construction for private and public buildings (and associated occupancy permits for these facilities), environmental emission laws and standards, etc.” Kappenman Comments Before the FERC.
“If insurance companies charge more for insurance to electric utilities that have not taken steps to mitigate the threat from geomagnetic storms, this may provide the incentive necessary for power companies to take steps to mitigate the threat.” Notes from a conversation with John Kappenman, 8/6/2013.
From a report by insurer Lloyd’s: “The insurance industry can play a key role in helping businesses and communities better understand the potential risks they face from solar storms and assist in mitigating these risks. In particular, some insurers are considering how to model the risks of geomagnetic storms on earth systems and apply expertise and learning from more traditional catastrophe modelling to the impacts of solar storms.” Lloyd’s 2013, pg. 15.
“The end of the Cold War relaxed the discipline for achieving EMP survivability within the Department of Defense, and gave rise to the perception that an erosion of EMP survivability of military forces was an acceptable risk. EMP simulation and test facilities have been mothballed or dismantled, and research concerning EMP phenomena, hardening design, testing, and maintenance has been substantially decreased. However, the emerging threat environment, characterized by a wide spectrum of actors that include near-peers, established nuclear powers, rogue nations, sub-national groups, and terrorist organizations that either now have access to nuclear weapons and ballistic missiles or may have such access over the next 15 years have combined to place the risk of EMP attack and adverse consequences on the US to a level that is not acceptable.
Current policy is to continue to provide EMP protection to strategic forces and their controls; however, the end of the Cold War has relaxed the discipline for achieving and maintaining that capability within these forces. The Department of Defense must continue to pursue the strategy for strategic systems to ensure that weapons delivery systems of the New Triad are EMP survivable, and that there is, at a minimum, a survivable “thin-line” of command and control capability to detect threats and direct the delivery systems. The Department of Defense has the capability to do this, and the costs can be within reasonable and practical limits.” Foster et al. 2004, pg 47.
“Congress has considered bills to require power companies to mitigate the geomagnetic storm threat. In 2010, the House passed the GRID Act, which would have required protections against the risk from storms. The bill died in the Senate, however. The bill was revived in 2013 as the SHIELD Act. It has yet to be voted on in either chamber.” Notes from a conversation with John Kappenman, 8/6/2013.
“The US leads the world in responding to the threat of geomagnetic storms. The UK and other countries are starting to move in the same direction as the US.” Notes from a conversation with John Kappenman, 8/6/2013.
“FERC/NERC: At the federal level, the Federal Energy Regulatory Commission (FERC) regulates the power industry. FERC lacks the power to devise regulations itself. Instead, FERC asks the North American Electric Reliability Corporation (NERC), a non-profit set up by the power industry, to devise standards to mitigate the risk from geomagnetic storms. NERC’s process for setting these standards is supposed to be an open process allowing all stakeholders to participate, but, in practice, only electric power companies come to the meetings in large numbers. Once NERC devises standards, FERC can either accept the standards or remand them to NERC for amendment. Currently NERC is working on new standards for mitigating the risk from geomagnetic storms, which will be made public in one to two years from now. At that point, advocates for the public interest will have to decide whether to encourage FERC to accept or remand. It is unclear how long it might take to arrive at adequate standards through this process. So far, there has never been a design code for grid components that takes the threat of geomagnetic storms into account.” Notes from a conversation with John Kappenman, 8/6/2013
“In 2013, Maine passed a law requiring power companies to protect the grid within the state from geomagnetic storms.” Notes from a conversation with John Kappenman, 8/6/2013.
“Currently, advocates for the public interest have little money to advance their cause. Mr. Kappenman, for example, draws from his personal savings to finance travel to NERC meetings. In contrast, the power industry has lots of resources that it uses to oppose regulations. Philanthropists could sponsor more advocacy for the public good. Some advocates would like to go to NERC meetings but lack the funds to do so, so philanthropists could provide financial support to enable them to attend.” Notes from a conversation with John Kappenman, 8/6/2013.
“Currently, advocates for the public interest have little money to advance their cause. Mr. Kappenman, for example, draws from his personal savings to finance travel to NERC meetings. In contrast, the power industry has lots of resources that it uses to oppose regulations. Philanthropists could sponsor more advocacy for the public good. Some advocates would like to go to NERC meetings but lack the funds to do so, so philanthropists could provide financial support to enable them to attend. Philanthropists could also pay for GIC blocking devices, or advocate for public ownership of GIC blocking devices. This would avoid having to force reluctant power companies to purchase the devices themselves. Alternatively, philanthropists could fund research on the threat or on mitigation measures. A variety of research is currently ongoing.” Notes from a conversation with John Kappenman, 8/6/2013.
“Reduction of equipment loading by re‐dispatch of generation, returning outage equipment to service, starting off‐line generation, and selective load shedding has the following benefits:
1. Allows the equipment loading to tolerate the increased VAr and harmonic loading.
2. Reduces the transformer operating temperature, thus permitting additional temperature rise from transformer saturation.
3. Prepares for the contingency of possible loss of transmission capacity due to transformer loss.
Unloading the reactive load of operating generation will provide operating margin in the case of possible loss of system reactive capability from SVC and shunt capacitors. Shunt capacitive devices are particularly vulnerable to the increased system harmonics and may trip during such an event. Shunt capacitors become a short for the harmonics, thus possibly overloading the capacitor and being sensed by relaying. Modifying protective relaying to prevent unnecessary tripping of these assets due to GIC may be the single most important action to prevent voltage collapse during GMD events (see Chapter 6).
Reductions of system voltage through reduced generator and load‐tap changer (LTC) set‐points and less insertion of capacitors have the following benefits:
1. Reduces system voltage, which could allow the transformer to operate farther from the saturation points of the transformer core. The transformer would then require less excitation current when the magnetic flux is biased due to GIC.
2. Lowers system voltage, which can reduce the loading on the capacitor, allowing an increased harmonic loading of capacitors.” Geomagnetic Disturbance Task Force 2012, Pg. 80.
“One of the important functions of a nation’s space weather infrastructure is to provide reliable long-term fore- casts, although the importance of forecasts varies according to industry. With long-term (1- to 3-day) forecasts and minimal false alarms, the various user communities can take actions to mitigate the effects of impending solar disturbances and to minimize their economic impact. Currently, NOAA’s SWPC can make probability forecasts of space weather events with varying degrees of success. For example, the SWPC can, with moderate confidence, predict the occurrence probability of a geomagnetic storm or an X-class flare 1 to 3 days in advance, whereas its capability to provide even short-term (less than 1 day) or long-term forecasts of ionospheric disturbances—information important for GPS users—is poor.” Severe Space Weather Events 2008, pg. 4.
“For now, since power companies do not have GIC blocking devices on hand, the safest response to a forecast of high risk of geomagnetic storms would likely be to shut down the grid for the duration of the period of high risk. This would protect the grid from harm. However, the grid might have to be shut down for days. Shutting down power across the US would be in itself an economic disaster costing billions of dollars. Installing GIC blocking devices would be cheaper than shutting down the grid even once. An order from the president is the most likely trigger for such a shutdown. However, it is uncertain whether a president would take such a step. The president has some related powers under the Constitution and laws passed by Congress. For example, laws allow him emergency control over coal-fired power plants and nuclear plants. However, the false alarm rate for major geomagnetic storms is high. A false alarm would damage the president’s power, so the president may be reluctant to shut down the grid.” Notes from a conversation with John Kappenman, 8/6/2013.
“Mr. Kappenman believes that ground-induced current (GIC) blocking devices are the best option for protecting against the threat to the grid posed by geomagnetic storms. Similar to an isolating foundation that prevents some of the Earth’s motion from being transmitted to a building during an earthquake, GIC blocking devices prevent the Earth’s charge from being transmitted to the transformer in a geomagnetic storm. GIC blocking devices have been shown to be feasible: they were tested in the 1990s and are currently being marketed. A paper that Mr. Kappenman coauthored determined that installing GIC blocking devices in transformers around the US would cost one billion dollars, which could be paid for by a 45 cent increase per person in annual electric bills. Most operators would prefer to keep GIC blocking devices on hand and install them when solar monitoring indicates a high probability of geomagnetic storms. Solar monitoring is good enough that we are very likely to have advance warning of geomagnetic storms.” Notes from a conversation with John Kappenman, 8/6/2013.
“Even with warning and alert procedures in place, operational mitigations may be overwhelmed by a sufficiently large storm. Hardening all critical infrastructures against geomagnetic storms is neither economically cost-effective nor technically possible. Hardening high-voltage transmission lines with transmission line series capacitors and the transformers connected to these lines through the installation of neutral-blocking capacitors is possible. But, doing so for all utilities supporting 345 MV and above would prove economically prohibitive (Molinski, 2000). For instance, since the 1989 Quebec electricity outage, Hydro-Quebec has spent more than $1.2 billion on transmission line series capacitors (Government of Canada, 2002). Although hardening all high-voltage transmission lines and transformers is not likely an economically viable strategy, OECD member governments should consider encouraging electricity generation companies and publicly owned utilities to harden transformers connecting critical electricity generation facilities to their respective electrical grids. Ensuring the survival of these high-voltage transformers in the event of an extreme geomagnetic storm will facilitate faster restoration of national electrical grids and remove part of the likely demand for replacement high-voltage transformers in an extreme geomagnetic storm scenario.” CENTRA 2011, pg. 51
“Satellite operators do not enjoy the economically beneficial option of relying on a wide range of operational mitigation of geomagnetic storm risk. Satellites in GEO can be temporarily moved into a graveyard orbit, an orbit hundreds of miles above a satellite‘s normal geosynchronous orbit where spacecraft are placed at the end of their operational life. However, this requires significant fuel and moving large numbers of GEO satellites into graveyard orbit in a short period of time preceding an extreme geomagnetic storm would raise require significant coordination between commercial satellite operators and national governments. Hardening a satellite‘s electronics serves as the primary space weather risk mitigation option. But, by increasing the satellite‘s weight, hardening makes it more expensive to launch. So, hardening is not frequently used in commercial satellite construction.” CENTRA 2011, pg. 44.