"Lightweight City" Pioneers a New Paradigm for the Future of Urban Development

On November 11, 2025, Professor Jianguo Lin—Fellow of the Royal Academy of Engineering (UK), Fellow of the Academia Europaea, Chair Professor at The Hong Kong Polytechnic University, Professor Emeritus at Imperial College London, and former Head of the Department of Materials and Mechanics at Imperial College London—along with Lin Xiao, Director of the Pudong New Area Development and Reform Commission, led a delegation to visit the Shanghai Key Laboratory of Urban Design and Urban Science (LOUD). The group engaged in exchanges focusing on topics including the research and practice of lightweight technology, and the "Lightweight City" initiative.

Professor Lin and his core team systematically presented a world-leading lightweight technology system centered on ultra-wide and ultra-thin extrusion technology for light alloys, in-situ bending extrusion technology, and thermoforming technology. This system integrates globally pioneering integrated forming processes for lightweight materials—such as Hot Forming Quenching (HFQ®), Differential Bending Extrusion (Flextrude®), and Wide Ultra-thin Extrusion (WiExtrude®)—along with AI data algorithm software. It has also established an industry-leading full-process simulation and large-model computing platform. Currently adopted by numerous internationally renowned enterprises, these technologies provide high-strength, lightweight, cost-effective, and sustainable system solutions for sectors including automotive, high-speed rail, marine vessels, aircraft, and 3C products.

Schematic Illustration: Taking high-speed rail and other rail transit vehicles as an example, Professor Lin explained that wide-plate extrusion technology can multiply the width of aluminum plates used in current carriage bodies, thereby significantly reducing manufacturing costs. Meanwhile, differential bending extrusion technology enables one-step forming of desired product shapes without the need for secondary processing. The application of these technologies not only substantially reduces vehicle weight but also enhances safety and manufacturing efficiency.

Director  Lin Xiao of the Pudong New Area Development and Reform Commission highly recognized the groundbreaking significance of the lightweight technology, noting that it fully aligns with the direction of the national 15th Five-Year Plan and Shanghai’s development positioning as an international metropolis. Director Xiao emphasized that Shanghai is one of the few international metropolises that still adheres to and actively promotes the transformation and upgrading of industrial manufacturing, having now entered a development phase of "leading in uncharted territory." Its main challenges lie in scenario innovation and consumer-oriented product breakthroughs. He stated that Pudong New Area will continue to increase investment in technological innovation, establish a substantial special sci-tech innovation fund, and provide strong support for the transformation of cutting-edge technologies. Additionally, Shanghai Pudong’s advanced manufacturing bases boast a solid foundation in the electronic information industry and extensive cooperation experience with leading enterprises such as Huawei, making them fully equipped with the solid foundation and implementation capabilities for collaborative innovation with Professor Lin’s team.

Rong Zou, Vice President of the Shanghai Federation of Modern Service Industries, Co-Chair of Shanghai Climate Week, and Executive Director of the UNITAR Prosperity Alliance Climate Week Research Institute, shared his long-term practices in promoting the development of sci-tech innovation services, addressing climate change, and advancing sustainable development. Director Zou pointed out that lightweight technology is one of the key pathways to achieving green, low-carbon, and sustainable goals, emphasizing that the development of this technology requires the joint efforts of multiple stakeholders. He expressed anticipation for leveraging Professor Lin’s team’s over 30 years of research accumulation in lightweight technology to promote the implementation and application of relevant technologies in Shanghai and across the country.

Professor Chenghe Guan, Co-Founding Director of LOUD, noted that every round of technological revolution in history has often originated from breakthroughs in materials science. He fully affirmed Professor Lin’s globally leading technology system, emphasizing that lightweight technology not only has a wide range of application scenarios but also serves as a crucial cornerstone for driving the continuous innovation of traditional industries. Building on this, Professor Guan innovatively proposed the concept of "Lightweight City," arguing that this concept will profoundly reshape the inherent structure and organizational logic of urban development:

• From "Incremental Expansion" to "Stock Optimization": Traditional urban development often relies on large-scale land and resource inputs (a "heavy" model). In contrast, a "Lightweight City" emphasizes improving the quality and efficiency of existing urban elements through technological innovation. For example, upgrading aging infrastructure using lighter materials instead of large-scale demolition and reconstruction aligns with the sustainable development direction of urban renewal.

• Reshaping Urban Internal Structure:

  1. Transportation Structure Transformation: The popularization of lightweight transportation vehicles, combined with new energy and autonomous driving technologies, may reshape urban transportation models and spatial layouts.
  2. Architectural Form Innovation: Lightweight and high-strength materials can grant greater freedom to architectural design, enabling more flexible and space-saving building forms that may even influence urban lifestyles.
  3. Resource Metabolism Upgrade: Lightweighting inherently means the efficient use of materials, reducing resource consumption and waste generation at the source, and making cities function more like efficient, low-carbon organisms.

Professor Lin expressed admiration for the vigorous development of Pudong New Area and deep agreement with the concepts of the Federation, Shanghai Climate Week, and LOUD. He noted that his team adopts a "research + industry" dual-driver model of industry-academia-research integration, leveraging the international top-tier R&D capabilities gathered at The Hong Kong Polytechnic University. Supported by several central enterprises, the team has established multiple research centers and undertaken numerous major national sci-tech research tasks. Their research and industrialization achievements in lightweight manufacturing can empower Shanghai’s manufacturing sector, are highly compatible with the sustainable development concept of Shanghai Climate Week, and can technically align with LOUD’s Lightweight City model. Professor Lin further stated that Shanghai and the Yangtze River Delta region—with their developed economy, talent concentration, and complete industrial chain—are ideal locations for establishing headquarters, R&D, and production bases, building a global lightweight technology center, constructing a complete lightweight industrial ecosystem, promoting the formulation of international lightweight standards, and attracting global high-end talent. He is confident in initially forming a scale within five years and building an internationally benchmarked highland for lightweight technological innovation within a decade.

Following in-depth discussions on topics including the research transformation of lightweight technology, scenario expansion, industrial collaboration, innovation model construction, and sci-tech finance platform support, LOUD will establish close cooperation with Professor Lin’s team. Guided by the "Lightweight City" concept, the two parties will launch research on new urban development pathways. The cooperation content and goals include:

1. Joint Research on Cutting-edge "Lightweight City" Topics: Focusing on this innovative direction, the two parties will systematically study the impact of lightweight technology on urban lifestyles in terms of material application, production manufacturing, and product innovation. The research will prioritize four core dimensions—"Light Materials," "Light Production," "Light Mobility," and "Light Living"—exploring how technological lightweighting can drive more efficient urban operations, low-carbon lifestyles, and friendlier urban spaces.

2. Jointly Building an International Platform for Lightweight and Sustainable Development Research Institutes in Shanghai and the Yangtze River Delta: Under the guidance and support of local governments, the two parties will construct a collaborative innovation ecosystem based on professional theories and technologies. Taking the International Lightweight Research Institute as the carrier, they will make systematic layouts in six key modules: technology transformation, industrial innovation, talent cultivation, sci-tech finance, standard formulation, and international cooperation. This will create a complete ecological system covering R&D, industry, capital, and the market, establish sustainable international cooperation mechanisms, and promote the application and popularization of lightweight technology in China and globally.

The Lightweight City and its related industries represent not only a technological innovation but also a transformation of urban development paradigms. By reshaping urban forms, industrial structures, and lifestyles through the mindset of "reducing weight and increasing efficiency," it provides a future pathway that integrates efficiency, resilience, and low carbon for high-density cities. LOUD, together with Professor Jianguo Lin's team, will actively promote the realization of the "Lightweight City," making it a "China Solution" that leads global urban sustainable development.