Factors such as war, climate change, technology, and public opinion are causing significant disruption and change in power generation. In this first of a two-part story, SCT’s Mario Pierobon identifies what resilience in the power sector is, typical threats on the power system, and strategies to improve power sector resilience.

According to Alexander Gilbert and Morgan Bazilian in a 2020 commentary entitled ‘Can Distributed Nuclear Power Address Energy Resilience and Energy Poverty?’[i] there exist three energy challenges that are driving energy decision making. “First, the need to mitigate and adapt to climate change. Second, despite recent progress, many communities in both developed and developing countries remain in energy poverty or lack reliable, low-cost energy services. Finally, due to climate-amplified natural disasters and other threats, the reliability and resilience of energy systems is an increasing public concern,” they say.

At the same time, emerging issues have made energy sector resilience a political issue. As the cornerstone of critical infrastructure, electricity supply is the focus of the operation of modern economies and social services. Power interruptions are costly and dangerous, Gilbert and Bazilian affirm. In this context, resilience development and decision making in nuclear and power generation have become very strategic topics.

Resilience in the Power Sector

According to Sherry Stout, Nathan Lee, Sadie Cox, and James Elsworth of the National Renewable Energy Laboratory (NREL) and Jennifer Leisch of the United States Agency for International Development (USAID) in a 2018 document entitled “Power Sector Resilience Planning Guidebook”[ii], resilience is defined as “the ability to anticipate, prepare for, and adapt to changing conditions and withstand, respond to, and recover rapidly from disruptions to the power sector through adaptable and holistic planning and technical solutions.”

The expression ‘resilience’ is assumed among nuclear engineers as a concept for enhancing nuclear safety and it is used to describe a large gamma of points of view, affirm Tatsuya Itoi and Naoto Sekimura in a 2017 book section entitled ‘Challenges for Nuclear Safety from the Viewpoint of Natural Hazard Risk Management’[iii]. “The concept of resilience is considered important when dealing with risk under large uncertainty. The concept of resilience is not introduced when risk is simply regarded as the possibility that something untoward may happen, but when it is regarded as something whose occurrence is rare but inevitable, to be managed when it in fact does occur,” they state.

According to Stout et al., reliable, secure, and affordable electricity supply is essential to driving economic growth and development. Energy systems are vulnerable to a range of natural, human-caused and technological threats, that can cause everything from blackouts to chronic energy shortages. “It is critical for policymakers, planners, and system operators to safeguard their power systems from these threats by proactively planning for future needs and investing in resilient power systems. Resilience planning identifies the threats, impacts, and vulnerabilities to the power system, and devises strategies to mitigate them,” they affirm.

Threats on the Power System

The impacts of these threats include potential shortages in transportation, power generation, fuel supplies, damage to physical infrastructure, changes in energy demand, and interruptions to end-user power supplies. These disturbances, in turn, can adversely affect critical services and facilities such as hospital services, water treatment and communication networks, Stout et al. affirm.

Identifying threats to the energy sector is an important step in planning a resilient energy system. A threat is anything that has the potential to damage, destroy or disrupt the energy sector, intentionally or unintentionally. Threats can be natural, technological, or human-caused and are generally outside the control of energy system designers and operators. They include the likes of wildfires, hurricanes, storm surges, and cyber-attacks. Natural threats include long-term climatic changes, such as variations in precipitation patterns and changes in air and water temperatures, as well as severe weather events, such as storms, flooding, and storm surges. Technological threats are often unpredicted equipment and infrastructure failures. Human caused threats include accidents and malicious events, Stout et al. explain. “Accidents involve unintentional actions that damage systems, such as a driver running into a transmission pole and causing an outage. Malicious events are the result of deliberate, harmful, human actions, such as physical terrorism or cyberattacks on power infrastructure and control systems. Physical attacks could injure workers and destroy energy infrastructure, such as fuel pipelines or transmission lines,” they state.

How to Improve Resilience

According to Stout et al., improving power system resilience requires to systematically identify and address vulnerabilities through proactive resilience planning. This can be done at multiple geographical scales and should be included within current power sector planning processes. “To perform a vulnerability assessment, planners initially gather data about critical loads, threats, energy resources, energy system infrastructure, and other relevant areas,” they say. 

Solutions may include options such as spatial diversification, development of microgrids for critical systems, introducing redundancy to the most vulnerable systems, and demand side management and efficiency, according to Stout et al. “Any of these solutions should be completed within an appropriate policy framework that values and enables resilience through infrastructure development and operational planning. It is also vital to identify financing that enables implementation of these solutions,” they affirm.

Summing Up

In this first part on resilience development and decision making in nuclear and power generation we have defined resilience, identified threats to resilience and strategies to improve power sector resilience. In the next and final part, we shall consider solutions for resilience development and some operational drawbacks.

[i] Alexander Q. Gilbert and Morgan D. Bazilian, Joule 4, 1839-1851, September 2020 Elsevier Inc.
[ii]Sherry Stout, Nathan Lee, Sadie Cox, and James Elsworth, Jennifer Leisch, POWER SECTOR RESILIENCE PLANNING GUIDEBOOK - A Self-Guided Reference for Practitioners, 2018. https://www.nrel.gov/resilience-planning-roadmap/.
[iii] Tatsuya Itoi and Naoto Sekimura, 2017 ‘Challenges for Nuclear Safety from the Viewpoint of Natural Hazard Risk Management’, published in ‘Resilience: A New Paradigm of Nuclear Safety - From Accident Mitigation to Resilient Society Facing Extreme Situations’