Electricity Sector Research Articles

Application of the environmentally extended input-output method in the identification of key sectors: A PRISMA-guided systematic review

The overarching goal of this systematic literature review is to identify, present and in detail analyze relevant published studies in Scopus-indexed publications regarding the identification of key sectors in the economy with the application of the environmentally extended input-output methodology (EEIO). For this reason, the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines for systematic literature reviews have been adopted. The Scopus scientific database was surveyed with the keywords “Environmentally extended input-output”, “key sectors”, “transmission sectors” and “key industries”, which led to a total of 50 published papers in English. After implementing all of the steps of the PRISMA guidelines, which included both electronic and manual searches, a total of 8 relevant papers remained for qualitative analysis. Most of these papers were conducted for the period between 2000 and 2017. The key findings are elaborated in a narrative synthesis and reveal that most authors indicate the electricity, transport and construction sectors as the sectors with the highest pollutant emissions; the household sector is also singled out as a sector that has a large impact on carbon emissions. The underlying purpose of this paper is to raise awareness and knowledge among scholars and local and national policymakers in regard to the key sectors and empirical ways for their identification with the application of the EEIO method. Lastly, the scientific and practical implications of the study are provided, and plans and guidelines for future work are presented.

Enhancing Risk Management: Leveraging the Likelihood/Severity Matrix for Effective Risk Assessment and Mitigation in the Electrical and Electronic Sector

This paper presents the basic concept of risk and reviews commonly applied tools and techniques for risk assessment. Generally, risk assessment is a completely experiential decision-making process based on experience and knowledge of risk assistants. This paper emphasises one quantitative/qualitative technique, namely the likelihood/severity matrix approach, which aims to direct the organisation’s attention towards risks that have the highest potential to have a negative effect. This paper’s main contribution lies in introducing a proposed model that utilises the likelihood/severity matrix approach to categorise risks into ‘regions’ and subsequently rank them. This process supports risk managers in making informed decisions to reduce risks effectively. A likelihood/severity matrix was examined through a case study belonging to the electrical and electronic sector to find the critical risks that hinder the assembly line of personal computers. Results showed that the ‘Breaking parts during assembly’, ‘Shocking the components from static electricity discharge’ and ‘Using wrong compatible parts’ risks had the maximum risk score, with values of 10–15 as the most critical risks. These results can influence decision makers in developing actions to mitigate these highlighted risks.

Green growth and net zero policy in the UK: Some conceptual and measurement issues

This paper examines how the likelihood of a transition to net zero could play out on the UK's total factor productivity growth over the longer term. It does this in the context of a potential trade-off between net zero goals and productivity growth. We begin by discussing the concept of green growth and a green industrial revolution, and then relate the green economy to the circular economy, as well as GDP measurement and how this relates to productivity growth under climate policies. We use a simulation method for the projected growth under net zero of the electricity sector in Great Britain to provide a context on the consequences of increasing input growth as output growth declines, and the result shows that the 2020s are challenging decades as productivity declines by −3.24 % p.a. in the electricity sector due to the combination of high input and low output growth. However, our findings reveal that the 2030s and 2040s look more promising, with productivity growth of 3 % p.a. and 1.6 % p.a. respectively as electrification increases and fossil fuel and labour inputs decline. Overall, the analysis offers a glimpse of just how challenging raising even maintaining the level of TFP will be in that sector in the earlier years out to 2050.

Decarbonizing the electricity sector using terawatt-scale interconnected photovoltaic power grids to meet the climate goals: A comprehensive review and a strategic roadmap

High scalability and quick deployability of solar photovoltaic (PV) make it an ideal candidate for rapid decarbonization of electricity. The typical SPV generation profile and power grids designed for conventional power plants (PP) are the major obstacles to maximizing SPV utilization. While energy storage systems (ESS) are often deemed critical, scalable ESS are site-limited, highly dependent on rare-earth elements, and either have higher embodied energy and emissions or low round-trip efficiencies. This manuscript demonstrates that by strategically interconnecting SPV power plants longitudinally, PV can meet base load demands and extend availability beyond peak-solar hours, thereby reducing the need for ESS and replacing existing carbon-intensive electricity infrastructure. It is demonstrated by modelling two 12 GW longitudinally separated transmission lines interconnecting SPVPPs situated 40° (case-1) and 90° (case-2) apart can provide PV electricity beyond solar hours for 4.69 and 7.33 equivalent hours (daily average), respectively. For cases 1 and 2, the lithium battery-ESS route can result in 4.76 and 3.35 times more carbon emissions and cost 4.23 and 2.98 times more than the transmission route, respectively, for providing the same energy over the transmission line's 40-year lifespan. Technologies such as multi-terminal ultra-high-voltage-DC grids, hybrid superconductive cables, new semiconductor materials for PV and energy systems, etc. are explored for the globally interconnected solar grid. Findings suggest 90 TWp of PV capacity can supply a significant portion of world's energy demand by 2050. This study outlines a comprehensive approach to build a sustainable and interconnected global solar energy infrastructure that aligns with climate objectives.

Sectoral electricity micro-spatial load forecasting based on partitional clustering technique

<p>Load demand forecasting is crucial in energy supply planning due to economic progress and territorial expansion, where land utilization transforms dynamically. An accurate sectoral load prediction can preclude the loss of beneficial opportunities arising from excessive load demand or excessive investment at a low-growth juncture. However, the particular area in this sectoral approach is still relatively large, rendering it incapable of precisely projecting load at minor points (micro-spatial). This study has proposed a micro-spatial load prediction strategy that categorizes identified areas into smaller grids or districts. This procedure includes clustering similar sites together for improved accuracy. K-Means is one of the partitional clustering approaches, a clustering algorithm utilizing object-based centroid-based partitioning approaches. The algorithm determines a cluster's centroid or centre as the average point for the cluster. This technique is advantageous as it can process extensive data efficiently and is appropriate for circular data. This technique can divide the data into multiple partitions, ensuring that each object belongs to precisely one cluster. Subsequently, mathematical modelling is used to predict the load of each cluster, which can then be utilized to more accurately evaluate the positions and sizes of prospective substations, transmission, and distribution facilities.</p>

Exploring the diffusion of low-carbon power generation and energy storage technologies under electricity market reform in China: An agent-based modeling framework for power sector

Promoting the widespread adoption of multi-complementary low carbon power generation technologies is a fundamental strategy for attaining carbon neutrality within the electricity sector. In the context of electricity market reform, this study develops an agent-based modeling framework integrated simulation with optimization. The model uses agent-based simulation to analyze annual market dynamics and low-carbon technology diffusion, with a two-stage optimization for energy storage and spot market simulation. The research findings indicate: (1) For different power generation technologies, the spot market can establish differentiated average prices, making the market price of carbon-captured coal power higher than that of conventional coal power, which are advantageous in reducing the subsidies required to promote the diffusion of carbon capture technology. (2) Expanding the spot market scale and implementing differentiated capacity compensation mechanisms both promote carbon capture technology diffusion. Nevertheless, with the marginal clearing mechanism, thermal power holds a average price advantage than renewable energy. Failing to control the growth of thermal power capacity will result in increased carbon emissions. (3) After 2030, energy storage's role in balancing supply and demand grows. Storage capacity should align with renewable energy scale and the regional characteristics of wind and solar resources to prevent overbuilding and stranded assets.

Remote-Sensing-Based Estimation of Rooftop Photovoltaic Power Production Using Physical Conversion Models and Weather Data

The global photovoltaic (PV) installed capacity, vital for the electric sector’s decarbonation, reached 1552.3 GWp in 2023. In France, the capacity stood at 19.9 GWp in April 2024. The growth of the PV installed capacity over a year was nearly 32% worldwide and 15.7% in France. However, integrating PV electricity into grids is hindered by poor knowledge of rooftop PV systems, constituting 20% of France’s installed capacity, and the lack of measurements of the production stemming from these systems. This problem of lack of measurements of the rooftop PV power production is referred to as the lack of observability. Using ground-truth measurements of individual PV systems, available at an unprecedented temporal and spatial scale, we show that by estimating the PV power production of an individual rooftop system by combining solar irradiance and temperature data, the characteristics of the PV system inferred from remote sensing methods and an irradiation-to-electric power conversion model provides accurate estimations of the PV power production. We report an average estimation error (measured with the pRMSE) of 10% relative to the system size. Our study shows that we can improve rooftop PV observability, and thus its integration into the electric grid, using little information on these systems, a simple model of the PV system, and weather data. More broadly, this study shows that limited information is sufficient to derive a reasonably good estimation of the PV power production of small-scale systems.

A worldwide analysis of stranded fossil fuel assets’ impact on power plants’ CO2 emissions

Will power plants emit less or more CO2 in anticipation of stronger climate policies that would strand fossil fuel reserves? Here, using a worldwide data source on individual power plants’ CO2 emissions and the value of countries’ at-risk fossil fuel assets, we show that between 2009 and 2018, plants emitted more CO2 in countries where more assets would be devalued under a 1.5 °C scenario, which we theorize is due to these countries’ regulatory leniency and plants’ vested interest in long-term fossil fuel contracts. Although the extra amount of carbon emitted each year trigged by imperiled assets is relatively small, it would exhaust a sizable portion of the electricity sector’s remaining carbon budget when added up over time. This is especially true in the U.S. and Russia where up to 16% and 12% of their budgets, respectively, could be spent within ten years due solely to the stranded asset effect.

Structural Effects of Economic Shocks on the Macroeconomic Economy–Electricity–Emissions Nexus in India via Long-Term Cointegration Approach

For developing nations to achieve net-zero targets, macroeconomic linkages impacting the decoupling of emissions from economic growth must account for non-linear business cycles and economic shocks. This study aims to delineate decarbonization policy pathways for the Indian electricity sector in the aftermath of COVID-19 by analysing the long-term evolution of the economy–electricity–emissions (3E) nexus during the 2008 financial crisis and during COVID-19, covering the period of 1996Q2 to 2020Q3. Upon testing multiple theoretical 3E systems, it was found that a model internalizing trade, inflation, and stochasticity was able to minimize the reproduction errors from growth to recession phases, as well as predict the rebound effect from an economic crisis. This was revealed to be due to more information within the coefficients in a trade stochastic model. Our results confirm the existence of electricity-associated emission decoupling with capital formation in the long-run, post-crisis, while economic growth and inflation increase CO2 emissions. The main finding highlights the negative feedback loop of inflation->trade->emissions, which shows that GDP and emissions are not directly causal. This long-run macroeconomic dynamic death spiral causes decoupling to be inhibited, where fossil fuel imports should not be subsidized for economic shock rebound, and the risk hedging of energy transition investments should occur in the post-COVID-19 era.

The Economics of Electricity and Development: Planning for Growth and a Changing Climate

Many low- and middle-income countries have made tremendous gains in electrification over the past few decades. These improvements in electricity access have enabled a growing body of empirical evidence on its impacts. This article complements prior reviews on the impacts of electrification by addressing several major remaining challenges faced by the electricity sector in developing countries—impediments to maximizing electricity services᾽ economic effects, obstacles to recovering utility costs, difficulties in forecasting future electricity demand, and uncertainty regarding the future adoption of climate-mitigating technologies—and the existing micro economic causal evidence addressing those challenges. We describe how randomized experiments have complemented the quasi-experimental evidence and then highlight some remaining gaps in the existing literature. Specifically, we highlight climate adaptation within the electricity sector in developing countries, which remains a crucial gap in both the discussion on and financing of electrification for development. We use case studies of Nepal and Pakistan in South Asia—a region that both recently experienced great electrification gains and is among the most vulnerable to climate change—to illustrate the need for additional work on adaptation in the electricity sector. We conclude by linking to recent discussions on climate adaptation finance.

Beyond the Meter: Understanding Consumer Satisfaction with Torrent Power in Bhiwandi

This thesis investigates consumer satisfaction with Torrent Power, an electricity distribution company operating in Bhiwandi, Maharashtra, India. It examines how various factors, including pricing, billing transparency, service quality, and grievance redressal, influence consumer perceptions and satisfaction. By employing a mixed-methods research design, this study explores the complexities of consumer-utility relationships in the Indian context. Findings reveal that while customers appreciate certain aspects of Torrent Power’s services, concerns about pricing, billing clarity, and power outages significantly impact overall satisfaction. Recommendations are provided to enhance customer experience and improve Torrent Power’s service delivery. This research contributes to the growing body of literature on consumer satisfaction in the electricity sector by providing insights into the specific challenges and opportunities faced by a distribution company operating in a developing country context. The findings of this study have implications for policymakers, industry practitioners, and consumer advocacy groups seeking to improve the performance of electricity distribution utilities.

Carbon pricing under electricity market constraints: analyzing rent management dynamics in the Republic of Korea

ABSTRACT How do policymakers manage the tension between enforcing a carbon price and ensuring low-cost electricity provision? This paper answers this question in two steps. First, it combines literature on electricity market design and rent management to arrive at a novel analytical framework. Carbon pricing can disrupt longstanding rent transfers between the state and electricity consumers by making it more expensive to produce and/or consume fossil fuel-based electricity. We theorize that policymakers respond to this dilemma by making incremental policy design adjustments to gradually enforce rent losses across the electricity production value chain. We apply this framework to study the implementation of the Korean emissions trading scheme (ETS) policy 2015–2022. Drawing on 20 expert interviews and policy documents we identify an initial sequence of policy design adjustments which enable, but also delay, the enforcement of the carbon price signal in the electricity system. This incremental and politically contentious process reduces the ETS policy’s ability to abate greenhouse gas emissions from the Korean electricity sector in the short term. The findings suggest that the effectiveness of carbon pricing in the electricity sector hinge on the parallel construction of supportive institutions to permit meaningful carbon cost pass-through.

Climate neutrality of the French energy system: overview and impacts of sustainable aviation fuel production

CO2 emission reduction of sectors such as aviation, maritime shipping, road haulage, and chemical production is challenging but necessary. Although these sectors will most likely continue to rely on carbonaceous energy carriers, they are expected to gradually shift away from fossil fuels. In order to do so, the prominent option is to utilize alternative carbon sources—like biomass and CO2 originating from carbon capture—for the production of non-fossil carbonaceous vectors (biofuels and e-fuels). However, the limited availability of biomass and the varying nature of other carbon sources necessitate a comprehensive evaluation of trade-offs between potential carbon uses and existing sources. Then, it is primordial to understand the origin of carbon used in sustainable aviation fuel (SAF) to understand the implications of defossilizing aviation for the energy system. Moreover, the production of SAF implies deep changes to the energy system that are quantified in this work. This study utilizes the linear programming cost optimization tool EnergyScope TD to analyze the holistic French energy system, encompassing transport, industry, electricity, and heat sectors while ensuring net greenhouse gas neutrality. A novel method to model and quantify carbon flows within the system is introduced, enabling a comprehensive assessment of greenhouse gas neutrality. This study highlights the significance of fulfilling clean energy requirements and implementing carbon dioxide removal measures as crucial steps toward achieving climate neutrality. Indeed, to reach climate neutrality, a production of 1,046 TWh of electricity by non-fossil sources is needed. Furthermore, the findings underscore the critical role of efficient carbon and energy valorization from biomass, providing evidence that producing fuels by combining biomass and hydrogen is optimal. The study also offers valuable insights into the future cost and impact of SAF production for air travel originating from France. That is, the European law ReFuelEU would increase the price of plane tickets by +33% and would require 126 TWh of hydrogen and 50 TWh of biomass to produce the necessary 91 TWh of jet fuel. Finally, the implications of the assumption behind the production of SAF are discussed.

Resolution Effort of Electricity Theft Crimes at PLN UP3 Sorong

This study aims to investigate the impact of electricity theft on PLN and the state and analyze the out-of-court resolution system for electricity theft by PT PLN UP3 Sorong Branch. The method used is an empirical juridical approach focusing on case analysis and field data. The results showed that PLN uses the additional bill, Tagihan Susulan (TS) as the fine, as an out-of-court resolution for electricity theft cases. However, there is an option to settle through the court if the customer objects. Although the number of cases is decreasing, challenges in addressing the problem of electricity theft still exist, and its resolution requires a holistic approach that considers the principles of justice and applicable law. In conclusion, electricity theft violates the law that must be addressed effectively to maintain the sustainability of the electricity sector and justice for all parties involved.

Relevance of guarantees of origin for Europe's renewable energy targets

To accelerate the transition towards an energy system based on renewable energy sources (RES), governments set targets for RES shares in their energy mixes. Renewable energy also plays a major role in decarbonization strategies of private organizations. Electricity from RES is claimed via the acquisition of market-based Energy Attribute Certificates, such as Guarantees of Origin (GOs). GOs can be traded within the European residual mix area. Interest in GOs is lower in countries with high RES shares, leading to a trade imbalance. In 2020, Iceland and Norway had a GO trade deficit that corresponded to 74.2 % and 62.4 %, respectively, of their gross final electricity production from RES. This study evaluates the non-dependence of Europe's RES targets and the GO system by including GO trade in the RES share calculations. Overall, 11 countries do not reach their 2020 RES targets for the electricity sector due to the inclusion of GO trade. Their total GO trade deficit amounts to 212 TWh, equivalent to 31 % of all issued GOs from RES. Limiting international GO trade to ensure that each country still achieves its RES-E targets is one option to harmonize governmental and corporate RES and decarbonization targets. Other options include the complete prohibition of international GO trade and a GO trade limitation to actual physical electricity transmission. Further aligning physical and virtual electricity consumption could strengthen the energy transition contribution of energy attribute certificate systems, such as the GO system.

Lost in transaction?: An institutional analysis of households’ transaction costs from demand-side grid management

Better utilization of the electricity grid is urgently called for, and demand-side management (DSM) measures are implemented to influence consumers' electricity consumption to off-peak periods. Little is known about how DSM measures generate private transaction costs for households, being crucial for the effectiveness and fairness of such measures. This article contributes to the energy transition literature by exploring sources of private transaction costs for households from a time-of-use tariff scheme for the grid in Norway. Data from nine group interviews reveal that uncertainty about the transaction (grid capacity), distrust of the transactor (grid provider) and the complexity of the institutional context (uncertainty about the electricity sector) increase transaction costs for households and reduce effectiveness of the tariff. Providing households with information on the reasons and methods for adjusting electricity consumption is essential, including the economic impacts on households of the new tariff. Additionally, households should receive enhanced guidance of technology use and behavior changes. For these two steps to work, trust in energy actors must be strengthened. Lastly, one should pay attention to the potentially undermining effect of such DSM measures on legitimacy of energy policies in general, given the unequal levels of transaction costs depending on households’ capital.

Transitioning Toward a Zero-Emission Electricity Sector in a Net-Zero Pathway for Africa Delivers Contrasting Energy, Economic and Sustainability Synergies Across the Region.

Although Africa contributes less than 5% to global greenhouse gas (GHG) emissions, its role in global climate action is pivotal. To date, 53 African countries have submitted their Nationally Determined Contributions (NDCs), and four have committed to a net-zero target. However, many of Africa's NDCs are vaguely expressed and without specific focus on explicit sectoral decarbonization targets. Furthermore, Africa's huge land-based carbon dioxide removal (CDR) potential remains unclear in the context of enabling net-zero (NZ) emissions within the continent. This study achieves two objectives: Under a NZ GHG emission trajectory in Africa, we uncover the implications of a targeted zero-emission electricity sector by 2030, on the energy landscape and other sustainability factors. This study also features the role of land-based biological removal methods─bioenergy carbon capture and storage (BECCS) and afforestation/reforestation (A/R)─in net zero actualization in Africa. Our results reveal a unified but disparate actualisation of the mid-century net zero emission goal across the continent, as all regions except North Africa achieve carbon neutrality. The industrial sector faces significant difficulties in transitioning and contributes substantially to positive emissions on the continent, with its share of total residual emissions reaching 49-64% by 2050. This difficulty persists even with targeted sectoral decarbonization of the electricity sector, although it is significantly reduced by the availability of BECCS as a CDR option. Under the zero-emission electricity pathway, emissions in buildings and transport sectors are reduced due to rapid electrification. A trade-off emerges in the net zero pathway concerning land allocation for negative emissions versus other land use activities. A key result shows that achieving a net zero target in Africa leads to a cumulative loss of $102 billion in fossil fuel infrastructure within the electricity sector by mid-century, which doubles when the zero-emission electricity goal is achieved.

Green hydrogen demand in Cameroon's energy sectors by 2040

Cameroon possesses a significant endowment of solar energy, granting it exceptional potential for the generation of hydrogen through environmentally friendly means. However, the continued expansion of the nation's petroleum industry presents an obstacle to the domestic utilization of green hydrogen due to its present costliness for energy purposes. Nonetheless, the prospect of exporting green hydrogen to developed nations remains an intriguing proposition. Indeed, a pact concerning hydrogen was established between Australia and Cameroon in the year 2021, thus opening avenues for the export of green hydrogen to facilitate the decarbonization of national energy supplies in Australia and other industrialized nations. Presently, there are no documented large-scale projects within Cameroon dedicated to the electrolytic production of hydrogen. This study projects the potential hydrogen demand in the electricity and transportation sectors up to 2040. Electricity demand is expected to be as high as 8675 GWh in 2040, while gasoline and diesel demand are expected to reach 1.75 and 3.26 million cubic meters, respectively. Therefore, the total amount of hydrogen needed to power both the electricity and transportation sectors is estimated at 0.532 megatonnes. Even a relatively modest allocation, merely 5 %, of Cameroon's land for the production of hydrogen via solar-powered electricity generation could yield a surplus. This resultant quantity of hydrogen, estimated at a substantial 16.68 megatonnes, would likely be more than enough to satisfy the projected domestic needs for both electrical and transportation uses by the year 2040.

Finding opportunity in economic power dispatch: Saving fuels without impacting retail electricity prices in fuel-producing countries

In many oil- and natural gas-producing countries, fuels are allocated to the electricity sector at administratively set prices below international market prices for domestic policy reasons. This article shows that dispatching power units based on the opportunity costs of domestically used fuels can yield significant efficiencies, while end-user electricity prices can continue to reflect administratively set fuel prices. In addition, opportunity cost dispatch can bring environmental benefits when it results in switching the priority of oil and gas units in the merit order and facilitating investments in renewable energy. Therefore, this approach can support long-term net-zero emission targets. It can also resolve cross-border electricity trading issues faced by fuel-rich countries, which are reluctant to base their electricity exports on domestic fuel prices.

Operational Technology resilience in the 2023 draft delegated act on cybersecurity for the power sector—An EU policy process analysis

The EU’s 2020 Cybersecurity Strategy promotes cybersecurity as essential for building a resilient, green, and digital Europe. Cleaner energy sources such as wind and solar are more volatile and thus need digital integration with Industrial Control Systems (ICS) for grid balancing. However, the digitization and the properties of cyberspace provide the ability to coordinate disruptive cyberattacks against power grid infrastructures. Digital weapons may be launched against ICS to start multiple cascading outages with a keystroke, causing large-scale blackouts we have never seen before. To reduce risk, the EU’s Strategy describes three objectives for ICS: Secure-by-design, resilient, and timely patched. In the strategy, the European Commission suggests a ”network code,” i.e. a delegated act for the electric power sector, setting rules for cybersecurity in cross-border electricity flows. The draft delegated act of November 2023 presents security requirements for Information and Communication Technology (ICT) and Network and Information Systems (NIS). Although ICS systems are used directly to manage electricity flows, ICS is only mentioned in one of the delegated act’s recitals as a subcategory of ICT products. Suppose Information Technology (IT) rather than Operational Technology (OT) is the focus of the delegated act. In that case, policymakers may not fulfill the EU cybersecurity strategy’s ICS objectives, thus failing to improve the resilience of power grid infrastructures and cross-border electricity flows. This study is a policy process analysis, and its contribution is threefold. First, a literature review is conducted to understand the extent to which the delegated act covers OT. Second, a framework condition analysis is applied to understand why the delegated act lacks OT-specific security requirements. Third, the analysis is extended to understand whether OT is sufficiently covered to achieve the EU strategy’s ICS objectives. In conclusion, our analysis shows a strong intention to include OT-specific security in the preparatory work of the delegated act, but that a stronger position of the IT communities forced OT onto the sideline. Further, the study shows weak fulfillment of general secure-by-design principles and security patch management. These results indicate that OT coverage in the delegated act is not in line with the expectations of the EU’s cybersecurity strategy and the delegated act’s early preparatory work. Therefore, we have suggested three measures to increase OT resilience focus in the act: (a) Define the expressions NIS, ICT services, ICT processes, and ICT in general as umbrella terms that include OT, (b) The foreseen minimum and advanced cybersecurity controls should require OT-specific measures, including holistic secure-by-design principles and patch management covering all patching phases, (c) Develop an OT implementation guide for the delegated act. Our work can be used by policymakers to optimize cybersecurity policy processes and by researchers studying socio-technical gaps in the cybersecurity domain.