Photovoltaic Industry Research Articles

Approaching 20% Efficiency in Ortho-Xylene Processed Organic Solar Cells by a Benzo[a]phenazine-Core-Based 3D Network Acceptor with Large Electronic Coupling and Long Exciton Diffusion Length.

High-performance organic solar cells often rely on halogen-containing solvents, which restrict the photovoltaic industry. Therefore, it is imperative to develop efficient organic photovoltaic materials compatible with halogen-free solvents. Herein, a series of benzo[a]phenazine (BP)-core-based small-molecule acceptors (SMAs) achieved through an isomerization chlorination strategy is presented, comprising unchlorinated NA1, 10-chlorine substituted NA2, 8-chlorine substituted NA3, and 7-chlorine substituted NA4. Theoretical simulations highlight NA3's superior orbit overlap length and tight molecular packing, attributed to interactions between the end group and BP unit. Furthermore, NA3 demonstrates dense 3D network structures and a record electronic coupling of 104.5 meV. These characteristics empower the ortho-xylene (o-XY) processed PM6:NA3 device with superior power conversion efficiency (PCE) of 18.94%, surpassing PM6:NA1 (15.34%), PM6:NA2 (7.18%), and PM6:NA4 (16.02%). Notably, the significantly lower PCE in the PM6:NA2 device is attributed to excessive self-aggregation characteristics of NA2 in o-XY. Importantly, the incorporation of D18-Cl into the PM6:NA3 binary blend enhances crystallographic ordering and increases the exciton diffusion length of the donor phase, resulting in a ternary device efficiency of 19.75% (certified as 19.39%). These findings underscore the significance of incorporating new electron-deficient units in the design of efficient SMAs tailored for environmentally benign solvent processing of OSCs.

Determinants of the development of photovoltaics in Poland

The photovoltaic (PV) industry is a rapidly growing sector of the Polish economy. The motivation for this study is the lack of detailed research on the impact of external factors on PV development in Poland. Therefore, we consider the different interests of various participants in the industry, encompassing installers; engineering, procurement and construction; designers; distributors; and manufacturers. The main objective of the study is to identify and analyse the legal, economic, environmental, technical and social factors that influence the development of PV in Poland and their determinants, considering the specific needs of different market stakeholders. The research is based on analysing the literature, publicly available reports and websites to complement the findings from in-depth interviews and surveys conducted among key PV market participants. Computational methods are employed, including Bartlett's sphericity tests, and the adequacy of the correlation matrix is evaluated using the Kaiser–Mayer–Olkin coefficient. The research results identify the main determinants of PV industry development in Poland, which include the lack of connection capacity, the cost of non-RESs and hourly pricing in the prosumer billing system. The study also determines the different perspectives between market stakeholders, finding that social factors have little impact on PV industry development. The main conclusion of the study is that the identified barriers must be addressed and removed to ensure the stable development of PV in Poland.

Homogeneous HER electrocatalysis using monothiolate ligand-based {FeS} complexes: A review

Renewable energy sources are considered as efficient, low cost and sustainable energy systems with the capability of achieving a decarbonized world. Of particular interest has been the use of hydrogen as an affordable and clean energy for achieving a sustainable (renewable) energy economy. The hydrogenases discovered almost 90 years ago and found in green algae and anaerobic bacteria, are known to be highly efficient biological catalysts for hydrogen evolution in nature. Out of the three types of hydrogenases ([FeFe], [NiFe] and [Fe] only) the [FeFe] hydrogenases have drawn particular attention due to their higher activity/efficiency and their ability to reversibly reduce protons to dihydrogen. Several models of the [FeFe] hydrogenase enzymes have been reported over the last three decades. This review article mainly describes in details the characteristics of mono- and di-nuclear {FeS} complexes with monothiolates (-SR) as the bridging ligands that have been reported as electrocatalysts for the hydrogen evolution reaction (HER).

A sustainable mineral process for silicon and quartz recovery from quartz crucible waste ash via electrical separation

Driven by the explosive development of the photovoltaic (PV) industry, the treatment of the quartz crucible waste ash (QCWA) from monocrystalline silicon rod production must be considered to combat the shortage of silicon materials and promote sustainable development. In particular, the loss of grade 4 N high-purity silicon in QCWA is a frustrating fact for the silicon supply chain. In this work, an electrical separation process is proposed for the recovery of silicon and quartz from QCWA to realize waste resource reutilization. The charging processes and forces in the feed QCWA are first analyzed. Then, the electric field distribution during electrical separation is simulated to clarify the movement models of silicon and quartz particles and formulate reasonable electrical separation parameters. After systematic theoretical analysis, calculation, and simulation, electrical separation experiments were conducted. The results prove that the content of silicon in the concentrate and the corresponding content of quartz in the tailing respectively exceeded 93 % and 61 % under a particle size of 80 ∼ 120 mesh, a voltage of 40 kV, and a roll speed of 75 r/min. This work demonstrates that electrical separation is a sustainable process that could be recommended for silicon and quartz recovery from QCWA.

How does the supply chain market respond to policy shocks? Evidence from solar photovoltaic sectors in China

Solar photovoltaic (PV) power policy implementation represents a pivotal strategy in addressing the challenges posed by global warming and climate change. This research endeavors to assess the effects of such policies on stock returns within the solar PV industry chain spanning the years 2013–2023. Employing contagion tests alongside the network analysis, our study delves into the intricate dynamics of policy impact. Our findings underscore the notably stronger influence exerted by opinion-based policies on policy contagion within industry chain sectors, eclipsing that of notification-based policies. Moreover, policies directed towards downstream sectors demonstrate a more pronounced effect on the mid- and downstream segments, relative to their impact on upstream components. Among the nine policies scrutinized, the 2017 notice pertaining to feed-in tariffs emerges as the most influential, driving and receiving policy shocks within the solar PV network system, while the 2022 notice aimed at coordinating the development of the PV industry supply chain exhibits comparatively weaker pervasive impact.

Renewable energy policy performance and technological innovation in Africa: A Bayesian estimation

This paper examines the effect of renewable energy policy performance on innovation activity in the renewable energy sector in a sample of thirty-three African countries during the period 2010–2021. The policy performance we use covers carbon pricing, incentives for grid-connected and distributed renewable energy generation, fiscal incentives for renewable energy, legal framework for renewable energy, off-take risk, network connection and pricing, and policy design attributes. Using patent data and renewable policy performance to fit a Bayesian negative binomial, our results generally show that renewable energy policy in the region supports technological innovation in the sector. Policy initiatives focused on market-based incentives (auctions and tariffs), renewable portfolio standards, risk mitigation, network connection and pricing are largely responsible for a strong and statistically significant relationship between renewable energy policy and innovation activity. We also find evidence that intellectual property rights, renewable energy capacity, electricity prices, affordability of renewable energy, and openness to trade proxies are important drivers of innovation activity in the renewable energy sector. Our analysis finds no evidence that research and development is a significant determinant of renewable energy innovation in African countries. Our results serve to inform policymakers on the areas in which specific policy actions are most effective at promoting innovation in the renewable energy sector.

Diamond wire saw forming cutting simulation analysis of arc workpieces

Abstract The application of diamond wire saws in the field of cutting hard and brittle materials is becoming increasingly widespread, especially in the photovoltaic industry where the demand for slicing processes for monocrystalline and polycrystalline silicon is continuously growing. Among these, the craftsmanship involved in arc-shaped workpieces is particularly complex. To analyze the impact of diamond wire saw processes on arc-shaped workpieces, PFC discrete element simulation software was utilized, aiming to produce a 1/8 arc segment, and the influence of the wire saw’s linear speed on the process was analyzed. The simulation results indicate that an increase in linear speed leads to improved particle distribution and a shape more closely resembling a circular form. However, the cutting process with a diamond wire saw must be controlled at an appropriate operating speed. If the speed is too high, it may lead to the destruction of the workpiece.

Transient response of a megawatt-scale solar photovoltaic in an electric distribution utility

There is an increasing trend among customers of an electrical distribution utility to adopt grid-tied solar photovoltaic systems. This shift offers multiple benefits to consumers, including lower monthly electricity bills and a contribution to the development of green energy. For the electrical distribution utility, various impacts may arise due to varying levels of solar energy penetration. This study investigates the effects of integrating varying levels of solar photovoltaic penetration into the commercial consumer network of Cagayan de Oro Electric Power and Light Company (CEPALCO) in the Philippines. Utilizing PowerWorld simulator, the research evaluates 11 different scenarios with solar penetration levels adjusted according to the percentage of load demand. Key findings include alterations in solar megavolt ampere of reactive power output, bus voltage levels, transformer power loading, and transmission line ampacity, with frequency levels remaining stable across scenarios. The optimal solar penetration level was identified at 70%, balancing the benefits of solar energy integration with the need to maintain grid stability and operational limits. This optimal level ensures the effective utilization of renewable energy sources without compromising the performance of CEPALCO’s electrical infrastructure. The research concludes with recommendations for maintaining grid stability and operational limits at the optimal solar penetration limits.

Upcycling of waste photovoltaic silicon: Co-MOF derived coating layer enhanced lithium storage

Large amounts of silicon waste (W-Si) powders or ingots from the photovoltaic (PV) industry can be recycled as the improved raw negative electrode material in Lithium-ion batteries. Herein, Co-MOFs (ZIF-67) is produced in the form of small particles which turns into the uniform coating layer on the surface of micro-sized W-Si by solvent evaporation, and then ZIF-67 is carbonized to form nitrogen-doped carbon (NC) layer and carbon nanotubes (CNTs). Finally, W-Si/NC/Co/CNTs composites are formed. The continuous and uniform NC layer and CNTs formed by the catalyzation of Co on the surface of the silicon particles can inhibit the volume expansion of silicon during the charge and discharge process, showing the reversible discharge capacity of 1039 mAh g−1 after 100 cycles. The rate performance is also improved due to the high conductivity composite structure. This work can provide a choice for the composite of MOF and micro-silicon, and the meaning guidance for the application of silicon waste from PV industry.

RENEWABLE ENERGY DEVELOPMENT TOWARDS SUSTAINABLE DEVELOPMENT GOALS: A REVIEW IN THAILAND AND THE PHILIPPINES’ LAWS AND POLICIES

Background and Purpose: Renewable energy (RE) plays a significant role in providing sustainable and clean energy as well as mitigating climate change. With the increased energy demand to support the growth of the economic sector, Thailand and the Philippines have moved towards improved energy cooperation, where renewable energy is an important subject matter in line with Target 7 of the Sustainable Development Goals (SDGs). Thailand and the Philippines have embarked on renewable energy projects and introduced numerous laws and policies to incentivise such an agenda. Nevertheless, the contribution of renewable energy in these countries' energy portfolios remains insignificant. Thus, this study aims to examine the current renewable energy laws and policies in Thailand and the Philippines, in assisting these countries to achieve the SDGs. Methodology: This study used a library-research methodology including statutory and conceptual approaches that focus on the laws and policies on renewable energy in Thailand and the Philippines. The utility of conceptual analysis is to understand the concepts and relevance of renewable energy and SDGs in the philosophies of environment, sustainability and law. Findings: Despite the fact RE provides opportunities in respect to socioeconomic development, energy access, energy security, and climate change mitigation, the existence of barriers to RE development leads to obstacles in accelerating RE’s share in the energy mix in Thailand and the Philippines. Comprehensive laws and policies to support renewable energy development are required to address these challenges. Nevertheless, legal frameworks are only one aspect that contributes to RE development. Governments' support through various incentives including financial and economic instruments are critical to navigating the transition toward a cleaner and affordable energy sector. Contributions: This study enhances the body of knowledge by examining the initiative for renewable energy development, advocating for comprehensive legal frameworks, and emphasizing the societal importance of government support to drive RE's role in sustainable development in Thailand and the Philippines. Keywords: Renewable energy, legal framework, policy, Thailand, Philippines. Cite as: Ghazali, F., Abdul Shukor, S. F., & Karim, R. (2024). Renewable energy development towards sustainable development goals: A review in Thailand and the Philippines’ laws and policies. Journal of Nusantara Studies, 9(2), 1-33. http://dx.doi.org/10.24200/jonus.vol9iss2pp1-33

Renewable Energy Sources in The Context of Emissions Reduction: Geographical Aspects And Challenges for Sustainable Development

Purpose: The study aims to provide a nuanced understanding of renewable energy sources' geographical aspects and challenges in reducing emissions and promoting sustainable development. Design/Methodology/Approach: This study adopts a qualitative approach to investigate renewable energy sources in the context of emissions reduction, focusing on geographical aspects and challenges for sustainable development. The methodology is designed to gain in-depth insights and understand the complexities of deploying and utilising renewable energy across different geographical regions. Case studies provide detailed, context-specific insights into the practical implementation and challenges of renewable energy projects. The selection of case studies follows a purposive sampling method to ensure diversity in geographical settings, types of renewable energy, and stages of development. Reviewing project reports, policy documents, and environmental assessments related to each case study. The data was analysed by cross-verifying information from different data sources to enhance the reliability and validity of the findings. Research Limitation/Implications: It justifies the immediate construction of a “green economy” in Ukraine, drawing on theory and the experience of advanced countries. Findings: The diversity of renewable energy sources, geographical influences, technological advancements, policy and regulatory frameworks, and socio-economic impacts influenced their efforts to reduce emissions. Social Implication: The modern global economy faces significant challenges such as energy security, sustainable development of society, and climate change. Practical Implication: The paper identifies directions and outlines paths and mechanisms for accelerated development. Indeed, such a powerful carbon dioxide and methane emissions surge has never been observed. Originality/ Value: Recently, the most pressing issue is the “carbon footprint”, which refers to the total amount of carbon dioxide and methane emissions released into the environment due to human industrial activity. Measures to combat it will soon focus on modernising technologies to facilitate the transition to the sixth technological paradigm and minimise greenhouse gas emissions. Critical technical solutions may involve harnessing the potential of hydrogen energy and immobilising or preventing greenhouse gas formation technologies. As an alternative direction, the authors consider research to solve some issues related to hydrogen production using metals.

Impact of the expansion ratio on the properties of hydrogen recirculation ejectors

Exploring the development characteristics and influencing factors of the mixing layer (ML) inside the hydrogen recirculation ejector is of great importance for enhancing the recirculation properties of the ejector and promoting green and sustainable energy development. However, the evolution of ML in the ejector and the transport and diffusion characteristics of the fluid are problematic, in particular, the influence of the expansion ratio on the properties of the ejector is unclear. Therefore, in this study, a CFD numerical model of an ejector was established to simulate the flow of fluids in the ejector. The evolution of ML was elucidated, and the interaction mechanism between the mixing and the recirculation performance of the ejector was revealed. The findings showed that the velocity difference is a significant driving force for the development of ML, and the formation of an adverse pressure gradient contributes to the diffusion of hydrogen and the rapid development of ML. The development process of ML in the ejector can be divided into three stages under the interaction of the velocity difference and the convective Mach number: the rapid growth stage, the slow growth stage, and the exponential growth stage. By studying the evolution of ML at different expansion ratios, it was found that there exists a critical expansion ratio for the ejector, which results in the largest of the non-mixing length ratio and the effective mixing thickness, the strongest relative mass transfer capability of the entrained flow, the fullest development of ML, and the optimal hydrogen recirculation performance.

Constructing magnetically propelled piezoelectric and pyroelectric bifunctional micromotors to boost the photocatalytic H2 production involving biomass reforming

Biomass-assisted photocatalytic water splitting for hydrogen (H2) production has attracted widespread interest, which is important for the development of green H2 energy and the high value-added utilization of biomass. Although photothermal utilization can improve solar energy conversion efficiency, the elevated temperature also enhances the likelihood of electron-hole collisions. Herein, magnetically propelled PVDF/Fe3O4@g-C3N4 spiral micromotors were constructed to easily foster the synergistic coupling of piezoelectric and pyroelectric effects, which is beneficial to enhance the directional migration of photogenerated carriers at high temperatures. With both piezo- and pyroelectric effects, the biomass glucose involved H2 production rate on PVDF/Fe3O4@g-C3N4 spiral micromotors is 42.3 μmol/h, representing a significant increase of 31.9 times compared to water splitting without these effects, and the average apparent quantum yield at ordinary pressure can reach 12.6 %. Furthermore, photoluminescence and variable-temperature electrochemistry demonstrate that the piezo-pyroelectric coupling can accelerate the separation of carriers. Meanwhile, COMSOL simulations and KPFM tests show that the built-in electric field of the sample is enhanced under the piezo-pyroelectric effect. The spiral micromotors can easily realize the synergism of piezoelectric and pyroelectric effects, which provides an effective strategy to enhance the built-in electric field and thereby improve the performance of photocatalytic H2 evolution involving biomass reforming.

Towards more reliable photovoltaic energy conversion systems: A weakly-supervised learning perspective on anomaly detection

With the increasing popularity of photovoltaic (PV) systems, both academia and industry have been paying growing attention to fault prediction and health management. Although deep learning has achieved remarkable results in this field, the high cost of labeled data acquisition has become a bottleneck for its application. While unsupervised methods can reduce this cost, they fail to effectively utilize the prior knowledge of anomalous samples. To address this issue, this paper innovatively proposes a weakly-supervised anomaly detection network based on feature map conversion and hypersphere transformation (FMC-HT). Firstly, PV electroluminescence (EL) images are input into the feature extraction layer based on feature map conversion, which can reduce redundancy, enhance information density, and achieve efficient feature extraction through feature map conversion. Subsequently, inverse squared norm loss is set to utilize the knowledge of unlabeled sample features and labeled anomalous sample features, and backpropagation is performed separately to train the hypersphere transformation network, ultimately achieving effective distinction between normal and anomalous samples. On real PV EL datasets, this model exhibits impressive performance and remains stable under different prior knowledge and anomaly rates. This study not only provides a new solution for anomaly detection in PV systems but also expands new directions for the application of deep learning in scenarios with limited labeled data.

Ultra‐Lean Silver Screen‐Printing for Sustainable Terawatt‐Scale Photovoltaic

As the photovoltaics industry approaches the terawatt (TW) manufacturing scale, the consumption of silver in screen‐printed contacts must be significantly reduced for all cell architectures to avoid risks of depleting the global silver supply and substantial cost inflations. With alternative metallization techniques (e.g., plating) facing their own challenges for mass production, advancements in the mainstream screen‐printing technology to accelerate the pace of silver reductions are urgently needed. This work presents a silver‐lean screen‐printed contact scheme, providing scope for substantial reductions in silver consumption based on existing industrial screen‐printing capabilities. The initial testing of such a design leads to the fabrication of 24.04% efficient large‐area TOPCon solar cells with 9 mg W−1 silver consumption compatible with existing soldering‐based interconnection technologies, corresponding to a 25%rel reduction in silver usage compared to standard industrial screen‐printed TOPCon solar cells. Upon further optimization in pattern designs and fabrication processes, this silver‐lean design offers a promising pathway toward ultra‐low silver consumption of less than 2 mg W−1 for screen‐printed TOPCon solar cells without sacrificing efficiency.

Operationally stable perovskite solar modules enabled by vapor-phase fluoride treatment.

The ever-increasing power conversion efficiency of perovskite solar cells has illuminated the future of the photovoltaic industry, but the development of commercial devices is hampered by their poor stability. In this study, we report a scalable stabilization method using vapor-phase fluoride treatment, which achieves 18.1%-efficient solar modules (228 square centimeters) with accelerated aging-projected T80 lifetimes (time to 80% of efficiency remaining) of 43,000 ± 9000 hours under 1-sun illumination at 30°C. The high stability results from vapor-enabled homogeneous fluorine passivation over large-area perovskite surfaces, suppressing defect formation energy and ion diffusion. The extracted degradation activation energy of 0.61 electron volts for solar modules is comparable to that of most reported stable cells, which indicates that modules are not inherently less stable than cells and closes the cell-to-module stability gap.

Optimal planning and operation of integrated energy systems in South Korea: Introducing a Novel ambiguity set based distributionally robust optimization

In this paper, we address the increasing focus on Renewable Energy Sources (RES) and energy policies in S. Korea, advocating for a shift from large, centralized power systems to decentralized Local Power Systems (LPS). This transition emphasizes the integration of Integrated Energy Systems (IES), which significantly enhances the target benefits for stakeholders in the power system. We have also adopted a Distributionally Robust Optimization (DRO) approach to account for the output uncertainty of RES and developed and applied new ambiguity sets tailored to each RES, enhancing the extensive robust design previously utilized with DRO. By applying our proposed ambiguity set-based DRO, we avoid excessive robustness and achieve superior optimal outcomes compared to the general DRO methodology, potentially making a significant contribution to business investment decisions. We have categorized the main stakeholders of the power system as Independent Systems Operators (ISO), Renewable Energy Providers (REP), Energy Exchange Aggregators (EXA), and End-users. The integration of IES leads to a benefit improvement rate of up to 34.8 %, 23.0 %, and 24.2 % for ISOs, REPs, and End-users, respectively, on a global scale. EXAs can secure an annual economic profit of up to $191,362.

Energy-efficient solar heat supply system based on hybrid photovoltaic collector

Following the commitments made under the Paris Climate Agreement, the scientific community has initiated a strategic increase in the share of renewable energy sources while gradually reducing dependence on traditional carbon fuels. Priority is given to the acceleration of the development of the photovoltaic industry, which has shown a constant increase in capacity over the past decades. According to the energy and climate strategies of the European Union, a significant increase in the amount of energy generation due to solar sources is planned. Therefore, the article is devoted to the development of a solar heat supply system based on a hybrid thermal photovoltaic solar collector with an improved design and analysis of the main characteristics of its operation using computer modeling. The authors have developed a 3D computer model of the proposed hybrid system with a solar collector by using SolidWorks software. The change in the temperature of the heat carrier in the hybrid thermal photovoltaic solar collector under constant solar radiation was analyzed. The temperature change of the coolant in the thermal accumulator of the system was also investigated. The results of the simulation of thermal processes revealed the key regularities of the temperature increase during the computer experiment, both in the hybrid thermal photovoltaic solar collector and in the thermal accumulator. The change in the instantaneous specific heat capacity of the developed solar collector was analyzed, and its average efficiency was estimated. The trends of changes in the thermal efficiency of the developed heat supply system during the computer experiment were determined. The novelty of the study is that the design of the hybrid thermophotoelectric solar collector has been improved, its 3D computer model has been developed, and the main thermal characteristics of the developed heat supply system with constant solar radiation have been obtained, which will contribute to the development of calculation methods for such heat supply systems with hybrid solar collectors in the future.

Exploring the complex interplay of green finance, business cycles, and energy development

Green finance has emerged as a contemporary mechanism to support investments in renewable energy, energy efficiency, and sustainable infrastructure projects. This study aims to provide empirical insights into the asymmetric influence of green finance and business cycle fluctuations on energy development in 60 developing countries from 2000 to 2021. Four aspects of energy development, including energy access, stability, efficiency, and production gap, are examined using panel quantile regression with additive fixed effects. The research findings demonstrate that green finance plays a significant role in fostering energy development, with varying effects across different quantiles of the distribution. Specifically, the results indicate that green finance supports energy access and stability, particularly during economic recession, low-income levels, and limited technological advancement. However, the impact of green finance on energy efficiency exhibits notable heterogeneity, contingent upon technological and periods of economic expansion. Achieving tangible improvements in energy efficiency necessitates a certain level of technological and economic development. Moreover, green finance shows a capacity to maintain an optimal level of energy production, particularly evident during economic expansion and for highly technologically developed countries. The impact of business cycle fluctuations varies across different quantile distributions of energy development indicators, predominantly exerting an inhibitory effect of economic recession. In light of these results, it is recommended that policies in developing countries be revised to enhance energy access, optimize energy production levels, and promote the cost-effectiveness of renewable energy in conjunction with green finance initiatives.

4E evaluation and optimization of a hybrid CCHP system integrated PEM fuel cell and adsorption chiller

In order to promote the sustainable development of green energy, this study developed a hybrid combined cooling, heating and power system primarily consisting of proton exchange membrane fuel cells and an adsorption chiller. The system is designed to provide both power generation and heating, while also offering cooling capabilities. Initially, the models of the proton exchange membrane fuel cell stack and adsorption chiller were rigorously validated against experimental data, showcasing remarkable consistency with discrepancies below 3.5 %. Subsequently, the investigation delved into the influence of operational parameters for the proton exchange membrane fuel cell stack and adsorption chiller on various performance. These metrics encompassed energy efficiency, exergy efficiency, annual costs, and annual greenhouse gas reduction. Finally, the NSGA-II optimization algorithm was employed to perform multi-objective optimization on the system. The outcomes demonstrated that, in comparison to the initial configuration, the optimized system achieved a 22.51 % reduction in annual greenhouse gas emissions, while simultaneously enhancing energy efficiency by 14.72 %, exergy efficiency by 0.34 %, cooling power by 3.14 %, and heating power by 42.63 %. Moreover, the annual cost experienced a substantial decrease of 69.86 %.