**1. Introduction**

The United Nations' (UN) 2030 agenda for Sustainable Development was announced in 2015 under the main title and objective of "Transforming Our World," and indeed, the world is witnessing transformations that are implemented and measured by the 17 Sustainable Development Goals (SDGs) and their indicators [1].

The SDG seven aims to ensure access to affordable, reliable, sustainable, and modern energy for all the world's population. The interaction of SDG 7 targets with the targets of SDG 1: No poverty, SDG 2: Zero hunger, SDG 3: Good health and wellbeing, SDG 6: Clean water and sanitation, SDG 8: Decent work and economic growth, and SDG 13: Climate actions have been analyzed and the mutual impacts identified to be reinforcing, enabling, or constraining. In addition, the mutual influence between SDG 7 and the other 16 SDGs has been presented [2], which demonstrated that energy sustainability is crucial for sustainable development.

The discussion and analysis of energy sustainability have been approached in the literature by several methods. A procedure has been proposed to evaluate the Sustainable Useful Index of energy-producing processes. The index assesses the ability to maintain the viability and usefulness of energy sources considering the produced, spent, avoided, and direct energy. The definition does not satisfy the broad concept of energy sustainability [3]. Within the same perspective, energy sustainability analysis has been performed at short-

**Citation:** Mohammed, M.S.H.; Alhawsawi, A.; Soliman, A.Y. An Integrated Approach to the Realization of Saudi Arabia's Energy Sustainability. *Sustainability* **2021**, *13*, 205. https://doi.org/10.3390/su 13010205

Received: 17 November 2020 Accepted: 17 December 2020 Published: 28 December 2020

**Publisher's Note:** MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

**Copyright:** © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/ licenses/by/4.0/).

term and long-term levels and applied to a case study on the production of distributed H2O [4].

Energy sustainability analysis for developing countries in the light of SDGs has been attempted. However, the authors limited the discussion on the role of a hybrid power system in improving energy sustainability in urban areas making a case study based on data from an Iranian city [5].

The authors of [6] have studied non-renewable energy and renewable energy efficiency for simultaneous achievement of economic growth and environmental sustainability in the Middle East and North Africa. The scope of the study has not included some important aspects of energy sustainability, such as the social dimension (energy equity and affordability).

Grigoroudis et al. presented a definition and mathematical model based on various indicators that cover the adequacy, reliability, affordability, social, and environmental requirements. The model rates energy sustainability on a 0 to 1 scale using Fuzzy Logic reasoning. The methodology is more integrated than the previous studies, however, one shortcoming is the potential subjectivity associated with assessment by Fuzzy Evaluation [7].

One of the comprehensive and informative methodologies on the performance of energy sustainability is World's Energy Trilemma Index (WETI) [8], published since 2010 by The World Energy Council, the UN's accredited energy body. Consistent with the World Energy Council definition of energy sustainability, the WETI ranks the countries energy performance on three dimensions: Energy security, energy equity, and environmental sustainability. The index helps to assess the effectiveness of energy policies for enabling balanced transition management, perform a comparative analysis using the experiences of countries with relevant socioeconomics and energy infrastructure, and eventually inform the policies on the required adjustments.

The WETI has been investigated using several methods to assess its reliability. The research in [9] has praised the value of the WETI in guiding countries to address the energy trilemma. Nonetheless, it has argued that the preferences among the trilemma can change from country to country, which requires weighing the trilemma dimensions adaptably. The research suggested the use of interval decision making and stochastic multicriteria acceptability analysis to measure countries' energy performance, and developed an alternative ranking scheme. In another contribution to addressing the preference variation of the trilemma dimensions, the interval decision matrix and the principal component analysis were used to evaluate the top ten performers in the 2015 version of WETI and produce a comparison rank that debated the weights assigned to the WETI indicators [10]. Principal Component Analysis has been applied to assess the methodology of the WETI using Pearson Correlation test, Kaiser–Meyer–Olkin Measure of Sampling Adequacy and Bartlett's Test of Sphericity. The conclusion was made from the results of Cronbach's Alpha test, and the authors deemed the WETI ranking unreliable [11].

Nevertheless, the methodology of WETI has been revised over the years since its first release, the most recent revisions were in the 2019 version that included the data sources, indicators, weighting, and indexation [8] (p. 42) and further refinements in 2020 report [12] (p. 63).

The ranking is based on grading the performance of each of the dimensions from A to D. Although Saudi Arabia is the world's leading oil producer and is among the top 20 countries in terms of Gross Domestic Product (GDP) [13], it was ranked 78 out of 127 in the 2019 WETI, mainly because of the poor performance in the Environmental Sustainability dimension scoring 35/100 (D) and the average performance in the Energy Security 55/100 (C), while scoring 98/100 (A) in the Energy Equity.

Saudi Arabia's ranking in 2019 retreated from positions 47, 53, and 47 in the years 2016, 2017, and 2018, respectively. In the years from 2016 to 2018, Saudi Arabia kept a consistent grade of BAD. Therefore, the comparative ranking fluctuation could be attributed to the performances of other countries as their ranks were rolling up and down. The downgrade in 2019 ranking is mainly due to the decline in the energy security dimension that has

consistently been graded with B due to lack of energy diversity in the past three years, to a C grade in 2019, which again can be attributed to the outpace of other countries besides the geopolitical tensions in the region. The strength of Saudi Arabia in the energy trilemma is in the energy equity dimension due to the availability and affordability of fuel and electricity.

The 2020 WETI was released recently [12]. Saudi Arabia is ranked 55 out of 108 countries, however, the progress from 78 in 2019 does not indicate a corresponding improvement in energy sustainability performance since the grade is still BAD. The quasi progress could be because fewer countries were included in 2020 and also because of the performance swings of the other countries.

In 2018, Saudi Arabia's total primary energy supply was 133,291 ktoe of oil and 78,009 ktoe of natural gas, 221,836 GWh of the electricity was generated from natural gas, 125,860 GWh from oil, and 155 GWh from solar Photovoltaic (Solar PV) [14]. The access to electricity covers 100% of the population [15], and the fuel and electricity prices, although they have recently been witnessing subsidies reforms, are still affordable. The presented figures explain Saudi's Energy Trilemma Index high score in energy equity and the low score of environmental sustainability. Moreover, the statistics show the reliance of the Saudi economy and the energy sector on oil and gas consumption and exports, which impacts the energy security score.

However, in recent years, and simultaneously with the efforts of the world to undergo an unprecedented transition to sustainable development, Saudi Arabia has announced an ambitious transformation plan known as Vision 2030 [16] that was built around three pillars: A vibrant society, a thriving economy, and an ambitious nation. One of the objectives of the vibrant society pillar is the maintenance of environmental sustainability, with one of its measures being the reduction of air pollution. The thriving economy pillar mainly aims at economic diversification, and it includes the objective of introducing renewables to the country's energy mix, increasing the production of natural gas, and controlling energy consumption by introducing plans for fuel-targeted subsidies. The objectives mentioned above support the implementation of programs that can lead to enhancing energy security and environmental sustainability.

There are two main trends in the literature about the energy sector in Saudi Arabia, one is about alternative energy sources, mainly renewables, and the other is on energy economics. The status and potential of renewable energy resources in Saudi Arabia have been reviewed, and the possible roles of renewable energy in developing policies for secured and cost-effective energy have been examined [17]. Renewable energy solutions for the challenge of increasing oil consumption in Saudi Arabia have been discussed as well as the outlook of energy cost and clean environment [18]. The human resources requirements to meet the future of renewables in Saudi Arabia have been presented [19].

Regarding energy economics, different policy scenarios to decouple the reduction in fuel consumption and energy cost increase or optimizing the prices of industrial fuels and household electricity [20–22] to seek a more efficient energy system have been discussed.

The presented literature gives useful insights and solutions, however, they considered siloed elements of the energy system, which have not addressed the holism of energy sustainability.

This work proposes to apply the holistic approach of the system thinking [23] utilizing Bayesian Belief Network (BBN) to examine the influences of the indicators underpinning the implementation of energy security, energy equity, and environmental sustainability in Saudi Arabia's context. The reached comprehension uncovers the probabilities of the impact and mutual interactions between the indicators and the likelihood of changes. The proposed method can support decision-making in energy policy prioritization, schedule, or amendments that can result in the improvement of Saudi's energy sustainability and WETI rank.
