Baypreg® STM employs the Spray-Transfer-Molding process, where PU resins are sprayed onto glass fibers and molded into battery covers, enabling efficient production of composite components. Developed in collaboration with Liyang Shanhu Industrial Co., Ltd., a Tier 1 supplier of automotive parts and battery packs to Chinese and international OEMs, this solution represents a significant advancement that is also cost-effective.

Solution for lighter and high-performance battery covers

This PU solution reduces battery cover weight by more than half compared to traditional steel shell materials. As a non-metallic material, the Baypreg® battery cover inherently offers superior anti-corrosion and insulation properties, effectively preventing electric arcing. When compared with non-metallic options, it outperforms in terms of surface smoothness and airtightness. It also demonstrates high strength meeting tough requirements from OEMs.

“As the inventor of polyurethanes, Covestro brings decades of expertise in the automotive industry, with PU solutions enhancing both driving and riding experiences in automotive interiors and exteriors. We can now extend this expertise to NEVs as well,” said Akhil Singhania, Global Head of PU Specialties at Tailored Urethanes, Covestro. “The Baypreg® STM solution showcases Covestro’s ability to deeply understand evolving market needs and rapidly innovate cutting-edge material solutions. Our goal is to deliver lighter, more efficient, and sustainable solutions through continuous technological innovation.”

The NEV industry has witnessed rapid growth in recent years. According to the China Passenger Car Association, NEV sales accounted for 51 percent of total passenger car deliveries in China in July 2024, outnumbering those of internal combustion engine vehicles for the first time.

Diverse applications for Covestro’s PU composites

At the CCE, Covestro will also showcase its PU composite solutions across various sectors. For instance, PU composites are widely utilized in photovoltaic (PV) modules to enhance efficiency and quality. Specifically, PU frames combined with coatings solutions from Covestro offer superior corrosion and weather resistance for PV modules, PU profiles excel in insulation and mechanical performance in energy storage batteries, and transparent front sheets based on composites enable high light transmittance while demonstrating exceptional strength for solar panels. 

Additionally, in construction, PU windows and doors are ideal for nearly zero-energy buildings due to their excellent insulation. In infrastructure projects, PU composites are widely used in power poles, railway sleepers and cable trays for their durability, weather resistance and low maintenance costs.

To learn more about Covestro's PU composite applications at the China Composites Expo, visit the company’s booth 7R19 in Hall 7.1 at the National Exhibition and Convention Center (Shanghai) from September 2 to 4, 2024.

Partially bio-based coatings raw materials for photovoltaic backsheets

Among the highlights is the introduction of a high-performance photovoltaic backsheet coating solution featuring a reduced carbon footprint. The low-carbon backsheet, developed in partnership with China’s Huitian New Material, incorporates the Desmodur^® CQ hardener, boasting a 70 percent renewable carbon content¹ derived from non-fossil-based inputs while ensuring no compromise on quality. To provide context, using Desmodur^® CQ in every 1 gigawatt of solar backsheets can result in the reduction of 41 tons of CO₂ emissions, equating to the annual CO₂ absorption of 10,000 trees. The CQ label is used to identify Covestro products with at least 25 percent alternative raw materials content.

Additionally, this innovative solution provides robust adhesion and exceptional weather resistance, guaranteeing a lifespan of over 25 years for backsheets. Its rapid drying properties also enhance production efficiency.

Solar panels with PU composite frames to endure harsh environments

Covestro will also showcase Baydur^®, a crucial auxiliary material for solar modules. The polyurethane (PU) composite frame made from Baydur^® resin offers excellent corrosion resistance, making it ideal for high humidity and high salt mist environments in coastal and offshore solar farms. As a non-metallic insulating material, the PU composite frame can reduce potential induced degradation, thereby enhancing the efficiency of photovoltaic modules. It requires no grounding and reduces the cradle-to-gate carbon footprint by 85 percent² compared to aluminum alloys. Baydur^® has obtained commercial material certifications from TÜV Rheinland and TÜV SÜD.

PU composites have demonstrated their durability across multiple industries for over four decades, enduring harsh conditions such as low temperatures, extreme wind loads and hail. Notably, the earliest project in China utilizing composite module frames made from Covestro’s PU resins has operated safely for over eight years.

Polycarbonate expertise addressing key trends in new energy products

As advancements in new energy products such as photovoltaics, energy storage, wind power and electric vehicles accelerate, the market demands stringent standards for safety, durability, weatherability, aesthetics and sustainability. At SNEC, Covestro will showcase its tailored polycarbonate solutions for new energy equipment enclosures, CMF (color, material, finish) design components, EV charging stations and premium storage batteries.

For instance, Covestro’s polycarbonates offer lightweight alternatives to metal for electromagnetic interference (EMI) shielding components, ensuring enduring outdoor electromagnetic shielding reliability when paired with conductive paint for equipment enclosures. Moreover, Covestro’s high-performance outdoor polycarbonate materials deliver outstanding weather resistance, mechanical properties and flame retardancy, making them ideal for resilient and secure battery systems. The Makrolon ^® polycarbonate utilized in battery enclosures and brackets withstands extreme temperatures down to -40°C and resists hydrolysis and UV aging.

SNEC stands as one of the largest exhibitions in the photovoltaic industry globally, encompassing PV manufacturing, materials, application products, modules, energy storage and mobile energy, spanning the entire PV industry chain. To explore Covestro’s material solutions in the PV industry and beyond, visit its booth at F006-007 in Hall 6.1 at the National Exhibition and Convention Center (Shanghai) or go to Covestro at SNEC 2024 | Covestro AG. 

¹ Value based on theoretical calculation (69 ± 4% renewable carbon, measured using the 14C method according to the ASTM-D6866 standard).

² Internal calculations based on data from TÜV SÜD, which shows cradle-to-gate carbon footprint of each kilogram of 100 percent primary aluminum profile is 24.2 kilograms of CO₂ equivalent emissions.

In the project, 30,000 square meters of PV modules were installed on rooftops, parking lots, and unused areas at Covestro Integrated Site Shanghai (CISS). The facility commenced operations in late January, and is projected to generate 6 million kilowatt-hours annually for on-site consumption. Coupled with the existing PV facilities, the site’s total solar power generation is expected to reach 6.5 million kWh annually, resulting in a reduction of approximately 5,000 tons of carbon emissions. This reduction is equivalent to saving about 2,000 tons of standard coal on an annual basis.

This initiative underscores the company’s unwavering commitment to advancing renewable energy utilization as a core aspect of its pursuit of full circularity. In 2023, renewable energy accounted for over 40 percent of the electricity used by CISS – the company’s largest production site – largely facilitated through multi-year Power Purchase Agreements with suppliers such as CGN New Energy. 

“Integrating this new PV power generation facility represents another stride towards emission reduction and achieving full circularity for our site,” said Dr. Yun Chen, General Manager of CISS. “While the solar power it generates contributes only a fraction to our site’s power consumption, the message is clear: we are committed to aligning all our activities with circular principles and want to contribute to the circular economy with the materials we produce.”

Enhanced energy efficiency of solar panels with PU composites

By integrating PV modules with frames partially made of its polyurethane (PU) composites into this project, Covestro also aims to leverage its materials expertise to contribute to the dynamics of the photovoltaic sector. The frame is a crucial component in solar panel modules, serving to safeguard glass edges, enhance sealing performance, and bolster overall mechanical strength.

Covestro, in partnership with China’s Zhejiang Deyilong, has introduced PU composite frames made of Baydur^® resin. These frames, utilized in the solar facility, demonstrate superior anti-corrosion performance. This durability renders them ideal for regions prone to high humidity and salt spray. As non-metallic insulating materials, PU composite frames mitigate Potential-Induced Degradation (PID), thereby enhancing the power generation efficiency of solar panels. Baydur^® composites have been certified by TÜV Rheinland and TÜV SÜD as suitable materials for solar panels.

Additionally, PU composite offers an 85 percent reduction in cradle-to-gate carbon footprint compared to traditional aluminum in solar frames due to its less energy-intensive production process.¹  

“This project not only reaffirms our commitment to advancing renewable energy in our factory production but also underscores the benefits of PU composites for solar panels,” said Akhil Singhania, Head of PU Specialties at Covestro’s Tailored Urethanes Business Entity. “This strategic initiative enables us to leverage our expertise and innovative solutions to meet the rising demand for sustainable energy solutions. By reducing our carbon footprint and optimizing resource utilization, we take pride in leading the charge towards a circular economy and driving positive change.”

¹ Internal calculations based on data from TÜV SÜD, which shows cradle-to-gate carbon footprint of each kilogram of 100 percent primary aluminum profile is 24.2 kilograms of CO₂ equivalent emissions.

This milestone was inked at Covestro’s booth during the China International Import Expo (CIIE), an annual event dedicated to promoting imports into China and fostering international trade and cooperation. The other partners are Jolywood (Suzhou) Sunwatt Co., Ltd., Zhejiang Deyilong Technology Co., Ltd., Changzhou Fusion New Material Co., Ltd., Shanghai Institute of Microsystem and Information Technology of the Chinese Academy of Sciences, and COSCO Kansai Paint & Chemical Co., Ltd. 

In alignment with China’s “double carbon” goals, the country continues to advance the reform of its industrial and energy structure, dedicating significant efforts to bolster clean energy, notably solar power. Leveraging its material expertise, Covestro plays a dynamic role in PV module production, elevating their efficiency and introducing alternative raw materials. This approach enables Covestro and collaborators to tackle technical challenges and advance the green transformation of the PV industry itself, while remaining attuned to evolving industry trends. 

Anand Khot, Senior Vice President of the Coatings and Adhesives segment of Covestro in Asia Pacific, said, “As a leading materials supplier, Covestro is committed to introducing viable new technologies and delivering differentiated services. At the same time, we aspire to empower the growth of the photovoltaic industry and contribute to the realization of a circular economy and climate neutrality through comprehensive cooperation with our customers.”

Diversified solutions

As a fresh and dynamic entrant in the PV industry, Covestro is poised to offer a wide array of material solutions through the newly launched platform. These solutions aim to enhance power generation efficiency, reduce module weight, and extend the service life of PV modules. Meanwhile, they empower customers to innovate and develop new products, all the while contributing to a reduction in their carbon footprint. For instance:

·       Covestro’s coatings raw material solution can ensure that two-sided coated backsheets achieve a light transmittance exceeding 93 percent, enable bi-facial PV modules to reduce their weight by 20 percent and increase power generation by 1.29 percent. Additionally, these modules exhibit outstanding aging resistance, guaranteeing a service life of over 25 years.

·       Covestro’s low-temperature photovoltaic silver paste polymer solution, integrated into next-generation cell technology, excels in enhancing photoelectric conversion efficiency. Furthermore, its capability to cure at temperatures below 200 degrees Celsius contributes to a notable reduction in energy consumption.

·       Decovery^®, a bio-based waterborne coating raw material, is a viable choice for coating containerized energy storage systems. By replacing conventional fossil-based solvent-borne materials, it reduces carbon emissions by more than 20 percent and effectively diminishes emissions of volatile organic compounds. Importantly, its application doesn’t require any modifications to the painting process, thus preserving work efficiency. This represents a step forward as Covestro extends its material applications from photovoltaic modules to encompass related energy storage systems for the first time.

·       Polyurethane composite frames for PV modules, made of Covestro’s Baydur^® resin, boast remarkable mechanical properties, featuring an axial tensile strength over five times that of aluminum alloy frames. Additionally, they demonstrate exceptional resistance to salt mist and chemical corrosion, rendering them suitable for coastal and offshore solar farms with elevated humidity levels. These frames, being non-metallic, contribute to mitigating power attenuation in the modules and eliminate the need for grounding. Overall, it is a more cost-effective solution with a significantly lower carbon footprint compared to aluminum alloy frames.

“Covestro’s innovative solutions offer us new opportunities and a brighter outlook for development,” said Cheng Xudong, General Manager of Jolywood (Suzhou) Sunwatt Co., Ltd. “We aim to optimize technological advancements and enhance energy efficiency to create sustainable PV products, thus propelling the progress of the PV industry through our collaboration.”

“Covestro is at the forefront of product development and innovation within the industry. We anticipate continued collaboration with Covestro to infuse fresh vigor into the photovoltaic sector, particularly in the realms of circular economy and achieving net-zero emissions, which will contribute to China’s green transformation and society development,” said Liu Zhengxin, a professor at Shanghai Institute of Microsystem and Information Technology.

Covestro aims to assist partners in the photovoltaic industry chain in creating products with higher added value and a reduced carbon while advancing their technologies. This will be realized through the utilization of alternative raw materials and the adoption of more sustainable production processes, ultimately driving the sustainable development of both the industry and society.

For a closer look at Covestro’s solutions for a fully circular future at the CIIE, visit us at booth 3B6-05, at the National Exhibition and Convention Center (Shanghai) from November 5 to 10, 2023.

The polyurethane certificate from TÜV SÜD serves as a fundamental certification for assessing the performance requirements of polymer materials in the photovoltaic industry. Under TÜV SÜD’s technical specification PPP 58208A, extensive testing was conducted on Covestro’s Baydur^® polyurethane resin, evaluating its mechanical properties, substrate physical properties, flame retardant grades, and heat resistance. The resin excelled across all parameters during the rigorous testing process.

During the ceremony, Zhang Zhulin, Operations Director of the Smart Energy Department and President of the Institute for Reliability and Standardization at TÜV SÜD remarked, “This certificate not only acknowledges Covestro’s Baydur^® resin for its exceptional performance and reliability, but also serves as a strong testament to Covestro’s R&D prowess in the field of polyurethane. TÜV SÜD remains dedicated to providing secure and sustainable solutions that safeguard individuals, the environment, and assets from technological risks, thereby fostering progress for businesses and society as a whole. We anticipate future collaborations with Covestro in advancing technology.”

The frame plays a vital role as an auxiliary material in solar panel modules. Its functions include safeguarding the glass edges, enhancing sealing performance, increasing overall mechanical strength, and facilitating the transportation and installation of photovoltaic modules. The performance of the frame directly impacts the service life of solar panel modules, aiming for an outdoor lifespan of approximately 25 years. Covestro has been developing innovative polymer solutions for the renewable energy industry over the years. In response to the solar industry’s demand for cost reduction and enhanced efficiency, Covestro introduced polyurethane composite frames made of Baydur^® resin reinforced with glass fiber through a pultrusion process. Covestro participated in the SNEC for the first time with exhibits at booth W2-388. The PU composite frames not only meet stringent mechanical properties and durability requirements, but also improve overall cost.

Furthermore, the PU composite frames exhibit superior resistance to acids, alkalis, and salt, surpassing the performance of aluminum alloy. This feature makes them highly suitable for high humidity and salt spray-prone areas. Additionally, as a non-metallic insulating material, the PU composite frames reduce the occurrence of Potential-Induced Degradation (PID), thereby improving the power generation efficiency of solar panels.

Markus Mingenbach, Vice President of PU Specialties at Covestro, said, “I’m very proud that Baydur^® polyurethane has received one of the world’s first polyurethane certificates for solar composite frames from TÜV SÜD. At Covestro, we place paramount importance on product safety. TÜV SÜD is an esteemed technology partner, and this certificate significantly enhances the technical credibility of composite frames for mass production. Moving forward, Covestro will collaborate with diverse stakeholders throughout the value chain, fostering technological advancements in the photovoltaic industry, and actively contributing to the realization of a circular economy.”

Obtaining authoritative certification marks a crucial milestone for the widespread adoption of new materials in large-scale production. Covestro has now obtained another international authoritative photovoltaic material certification, further enhancing the prospects of polyurethane composite frames. With this achievement, PV module manufacturers now have a new and compelling alternative to traditional aluminum alloy frames, offering excellent performance and competitive pricing.

Following the initial successful participation at the race in Australia 2017 as "Best Newcomer" and the third place at the European Solar Challenge 2018, the team now wants to build on these experiences and challenge the next step at the World Solar Challenge 2019. "There we want to take on the challenge of the world's leading developers from Delft, Michigan and Leuven in Belgium," says Markus Eckstein, first chairman for the Sonnenwagen Team.

As a leading global provider of innovative and sustainable materials solutions, Covestro shares the students' enthusiasm and will work with them to push the boundaries of that which is possible and make the project a success. Julia Cramer, heading the project at Covestro, explains: "We have been working together with the renowned RTWH Aachen for a long time and, after the successful cooperation in 2017, are now supporting the solar car project with a variety of materials and technical services as well as being the main sponsor". The primary objective is to test new materials under the extreme climatic conditions of the track.

Partnership for solar mobility

Global trends such as climate protection and the conservation of resources coupled with increasing mobility are forcing car manufacturers to rethink. Trends such as electric mobility, networking, autonomous driving and car sharing require totally new vehicle concepts and technologies. Lightweight and functional materials from Covestro reduce fuel consumption and play an important role in extending the range of electric vehicles, for example. They also impart the required stability.

Sustainability is a central component of Covestro's corporate strategy, and solar mobility could make an important contribution to climate protection and the conservation of fossil resources. That is why Covestro is supporting this ambitious project and intensifying its cooperation with the Sonnenwagen Team. Thanks to its innovative materials, the company is providing solutions for the mobility of the future. One of Covestro's forward-looking goals is to support automotive concepts in which vehicles generate energy while in motion. Another objective is to test materials that could later be used in other applications. Covestro is also promoting young talent with this project.

The new Covestro Sonnenwagen is scheduled to be presented to the public for the first time in Aachen on 22 July.

About Covestro:

With 2018 sales of EUR 14.6 billion, Covestro is among the world’s largest polymer companies. Business activities are focused on the manufacture of high-tech polymer materials and the development of innovative solutions for products used in many areas of daily life. The main segments served are the automotive, construction, wood processing and furniture, and electrical and electronics industries. Other sectors include sports and leisure, cosmetics, health and the chemical industry itself. Covestro has 30 production sites worldwide and employs approximately 16,800 people (calculated as full-time equivalents) at the end of 2018.

Find more information at https://www.covestro.com
Follow us on Twitter: https://twitter.com/covestro

Forward-looking statements

This news release may contain forward-looking statements based on current assumptions and forecasts made by Covestro AG. Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in Covestro’s public reports which are available at www.covestro.com. The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.

Covestro supports the various BMZ battery projects with material selection, during plastic-compatible component design and with CAE-based component simulations to meet the requirements of the UN Transport Test for Batteries (UN 38.3). Further services include moldflow analyses and technical injection molding support.

"Every battery project is technically demanding, which is why I am all the more pleased that plastics from Covestro can make an important contribution here," explains Jens Ufermann from Covestro, who looks after BMZ GmbH locally, adding: "Together with customers like BMZ, we are working on sustainable product and application developments to master the challenges of future battery technologies."

High requirements for stationary and mobile applications

Similar to battery systems for mobile applications such as cars, buses, scooters and pedelecs, energy density and safety are important aspects in the development of battery products for stationary use, as is the case with BMZ GmbH's energy storage systems.

"Our in-depth understanding of the diverse applications of battery systems and our many years of experience in materials for battery applications enable us to provide our customers with both technical expertise and suitable products," says Dr. Julian Marschewski, Market Development Manager in Electric Vehicle Battery Packaging.

Polycarbonate blends with tailored properties

Bayblend^® (PC+ABS) blends from Covestro play an important role in both mobile and stationary battery applications, for example in placing individual cylindrical battery cells in 18650 or 21700 format in a cell holder. To achieve this, the material must have excellent mechanical properties, above all high impact strength, but also high flowability in order to achieve the thinnest possible walls between the individual battery cells when manufacturing the cell holders through injection molding.

Additional safety in later use is provided by the incorporation of flame retardant grades that meet the high flame retardancy standards of Underwriters Laboratories according to category UL 94 V-0.

Broad range of products

The Covestro portfolio for battery applications continues to evolve. For cell holders for holding cylindrical battery cells, pouch cell frames, battery housings and similar applications the focus is on both unfilled (Bayblend^® FR3010, Bayblend^® FR3040) and mineral-filled (Bayblend^® FR3020, Bayblend^® FR3021) along with glass-fiber-reinforced (Bayblend^® FR3060 EV) flame retardant Bayblend^® products. Covestro also offers thermally conductive polycarbonate grades of the Makrolon^® TC product family that can contribute to battery thermal management.

This is the goal of "Solar Decathlon China", a student competition for building concepts that use only solar energy. The venue for this year's "Olympic games for solar energy and green building industry," as the organizers call the Decathlon, is the city of Dezhou. It is also known as the "Sun City" because it is at the center of the Chinese solar industry. 22 student teams from 37 universities from around the world will take part in the competition.

With know-how and material solutions, Covestro supports two student groups in the competition – the joint team of Tongji University Shanghai and TU Darmstadt, and the team Shunya of the Indian Institute of Technology in Mumbai.

Megacities as a challenge and opportunity

"The fast-growing megacities in these two countries present particular challenges to population supply, the development of the infrastructure and climate protection," says Dr. Markus Steilemann, CEO of Covestro. "At the same time, local universities and companies often develop the best solutions for global trends such as progressive urbanization."

Therefore, close cooperation with local partners is particularly important: "Together with them, we develop innovative and sustainable material solutions for energy-efficient buildings. On that basis we want to help shape future habitats and make the world a brighter place," says Markus Steilemann.

With such projects, Covestro is committed to achieving the 17 Sustainable Development Goals (SDGs) of the United Nations. Particular priorities are sustainable cities (SDG number 11) and the use of renewable energy (SDG number 7).

Solar Decathlon China: holistic residential solutions in demand

Each team was to design and build a one- or two-story solar house with a floor space of between 120 and 200 square meters. The solution is evaluated according to ten criteria: architecture, market appeal, engineering, communications, innovation, comfort zone, appliances, home life, commuting and energy performance.

On August 17, the winning concept will be announced. After that the area will be turned into a permanent exhibition for sustainable construction and into the first intelligent low-carbon park in China.

Sophisticated construction concepts

The EnergyPLUS Home 4.0 from Tongji University and TU Darmstadt has a modular structure, so that several units can be combined to form an apartment building. Covestro produces transparent and heat-insulating polycarbonate panels for the façade, as well as polyurethane raw materials for water-based, yet water-permeable outdoor floor coatings. They are a perfect fit for new city drainage systems like so-called sponge grounds that soak in water and direct it into piping systems underground.

Mumbai's Shunya team's Solarise concept combines regional architectural principles and includes climatic and cultural aspects. It is a net positive energy solar villa with a floor space of 150 square meters, which is suitable for a family of six people comprising all modern amenities for comfortable and sustainable living. Products from Covestro are used in insulating polycarbonate panels on the roof, in polyisocyanurate insulation panels in walls and floors, and in the coating of the steel framework.

In focus: renewable energies

“With the support of the Solar Decathlon China, Covestro also underlines its commitment to the expansion of renewable energies such as solar and wind power,” says Dr. Christian Haessler, head of Sustainability at Covestro and former head of its Polymer Research and Development Center in Shanghai. The company was the official sponsor of the Solar Impulse project of the pioneers Bertrand Piccard and André Borschberg, who for the first time circumnavigated the earth with a solar-powered aircraft. In addition, students from the RWTH Aachen University, who participated in a self-built solar car at the World Solar Challenge 2017 in Australia, arguably the toughest solar race in the world, were supported.

“Covestro is also involved in expanding wind power, especially in China,” adds Christian Haessler. “Together with partners, we developed a new polyurethane composite for rotor blades of wind turbines. These are more flexible and robust than conventional blades and can be made faster and more economically.”

Worldwide competition for solar construction

The first Solar Decathlon events took place from 2002 in the USA. Later offshoots were also established in other regions. The initiator and organizer continues to be the US Department of Energy. This year's Solar Decathlon China will also be hosted by China's Ministry of Energy and other national authorities.

About Covestro:

With 2017 sales of EUR 14.1 billion, Covestro is among the world’s largest polymer companies. Business activities are focused on the manufacture of high-tech polymer materials and the development of innovative solutions for products used in many areas of daily life. The main segments served are the automotive, construction, wood processing and furniture, and electrical and electronics industries. Other sectors include sports and leisure, cosmetics, health and the chemical industry itself. Covestro has 30 production sites worldwide and employs approximately 16,200 people (calculated as full-time equivalents) at the end of 2017.

More information can be found at www.covestro.com and www.career.covestro.com.
Follow us on Twitter: https://twitter.com/covestro

Forward-looking statements

This news release may contain forward-looking statements based on current assumptions and forecasts made by Covestro AG. Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in Covestro’s public reports which are available at www.covestro.com. The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.