Case Study extracted from Salat, Serge. 2021. Integrated Guidelines for Sustainable Neighbourhood Design. Urban Morphology and Complex Systems Institute 2021. © UMCSII.

Far from favouring a single vision of the city, French Dream Town in Hangzhou is a pluralist integrated project. The project is developed on a reutilized former site by Mrs. Fadwa Sube, Vice President of Ile de France Region European Deep Tech Cluster and is a cooperation between France and China. It is developed in Zhejiang Province, a breeding ground for innovation and creativity. French Dream Town in Hangzhou revisits all the components of our urban environment – energy, mobility, health, climate. The project takes advantage of innovative design, system integration, renewables and nature-based solutions to create a zero-carbon development, in line with the common vision for Green and Thriving Neighbourhoods. Hangzhou is a former imperial city which was the most populous city in the world. It was shining on techniques and the arts and is today one of China's most dynamic cities. Planning, architecture, materiality, green spaces, nature-based solutions, amenities, infrastructure, art, and cultural connections are all elements that contribute to the creation of a context driven and people-centric place. The development provides a sustainable lifestyle that is enhanced by A.I. (Artificial Intelligence), deep tech, and IoT (Internet of Things). 

Key partners and actors

China's New Urbanization Strategy aims to implement ecological and sustainable development, and to provide the population higher quality of life and services. The Western Innovation Corridor in Hangzhou includes a French-Chinese project called French Dream Town. The objective of the project is to be a multi-use space for exploring the city of the future, focused on sustainability, new urban lifestyles and culture. It is a French-Chinese collaboration between Optiva Darna, involving 30 tech companies of Systematic, Paris Region Deep Tech Hub, and Hangzhou Future Sci-Tech City, one of four such zones decided and supported by China's national government. 

The French Dream Town project followed two initial projects: an innovation platform (with the launch of 5 JVs) and a ‘French City Brain’ project (with the participation of 30 French and Chinese partners) focused on renewable energy management. The urban planning and architectural design of the project is carried out by Anouk Legendre (architect, XTU) for the southern part, and Serge Salat (architect – urbanist, president of the Urban Morphology and Complex Systems Institute) for the northern part. 

The French Dream Town’s impact areas

French Dream Town is an example of net zero creative neighbourhood. Creative industries, and shaping urban spaces with creative assets, will help spur new approaches to building societies and planning cities that are needed to stimulate – and maintain – innovation, efficiency, liveability, and inclusivity. According to the World Bank[1], when leveraged effectively, creative cities can contribute to three core impact areas:

Place making from cultural context, enriching the existing 

The place making vision is a contemporary transposition of classical Chinese landscape painting tripartite composition. Although integrated in its final state, the project was developed in two parts:

1. In phase one, the buildings of the South Part were designed like a Southern Song dynasty traditional village by Anouk Legendre.

2. In phase two, the buildings on the North Part, designed by Serge Salat, with their greater height, their curved solar canopies, their green roofs and green walls and the translucency of their facades are like the mountain and clouds on the top of the landscape while making the development carbon neutral.

In harmony with Chinese culture, this tripartite composition creates a positive Fengshui (風水), which uses energy forces to integrate the project with its surrounding environment. A description of the two phases is provided below. 

Southern part – Anouk Legendre (phase one)

Context-driven architecture with recreated Southern Song dynasty roofs. Roofs in the Southern Part of French Dream Town are inspired by Chinese Southern Song dynasty forms while being redesigned with mathematical algorithms. Their variations in height, modelled by digital tools, are architectural ‘undulations’. This can be appreciated from afar when on the other side of the river. The roofs rise one above the other, then lower when people reach a plaza. This creates variations in the intensity of construction. Thus, the urban atmospheres are varied, inviting the visitor to go from one to the other. The whole produces a large landscape of roofs with an urban rhythm between the two bridges. The urban landscape reinterprets the rolling landscapes of traditional Chinese villages.  

People centred public realm and nature-based solutions to experience nature in the city. The design creates three attractive centres: two squares at the entrances to the neighbourhood, at the level of the two bridges, and a large central square by the water. These three squares open onto the river and nature as privileged spaces for social life. From one square to another, people can move through semi-covered passages. This recreates the traditional scale of Chinese villages. Nature is layered between constructions. French Dream Town is a natural new space, taking advantage of Chinese gardeners’ skills. In this new conception of town planning, nature-based solutions become both an effective system solution and a design feature. The presence of water, plants, the work on shade and natural ventilation of buildings, effectively mitigates the heat island effect.

Northern part – Serge Salat (phase two)

The Northern Part is inspired by Feng Shui, a harmony between human culture and nature with water, mountains, clouds, and architecture elements.

The volumes are complex pavilions with terraced gardens inspired by the pavilions in Suzhou traditional gardens. Their internal volumes and circulation integrate multiple functions. Inner large open atria bring natural light and ventilation into the buildings and ensure vertical public circulation through iconic helical staircases. The building complex cubic volumes alternate openness and closure creating iconic facades on all their sides. The skyline is defined by a complex and rhythmic composition of curved photovoltaic canopies. These are also contemporary transpositions of Southern Song dynasty roofs. They both supply solar energy and shade the facades, reducing solar gains in summer. 

Hangzhou French Dream Town project is based on the encounter of contemporary zero energy design and Taoist principles: a rhythmic alternation of opposites, Yin and Yang (阴 阳, 陰陽), void and fullness, interior and exterior, ephemeral and tangible.

The facades filter the light and shade the buildings with a variety of transparent or translucent glass, and light screens made of glass and perforated metal. The external volumes are defined by diaphanous facades of glass, translucent glass, glass with serigraphy, glass with perforated silver screens, and punctuated with outdoor terraces.

The project is grounded in its cultural context. Connecting the interior and the exterior, the built form and nature is a method used in Chinese architecture. The Void which penetrates on all sides participates in the evocation of the ‘Median Void.’ In Chinese Taoism, it makes play the vital energy within matter. Open work stone or brick partitions and lattice windows act as spacing to produce an effect of both distance and visual integration. Clerestories, doors, and windows divide the outdoor scene into several sections. A similar effect is achieved in French Dream Town. Perforated aluminium panels let light enter the buildings while casting shadows.

Reaching zero net with bioclimatic design and renewables

Bioclimatic design strategies are integrated with smart and renewable systems, thus allowing to achieve zero energy for the entire development. 

Green design concept

The green design concept shapes the urban fabric to enhance shading, natural ventilation, accumulation of rainwater, three-dimensional greening, and collection of solar energy. The Hangzhou climate has very hot summers, mild winters, and is humid all year. Different sustainable systems both passive and active are used:

• Shading of the facades by large overhanging solar canopies.

• Natural ventilation: In the months of mild temperatures the buildings will work with natural ventilation. A practicable stripe on each window will allow the air in rooms using the central (hotel, apartments, A. I. West Wing) and perimeter (AI East Wing) atria as a ventilation shaft. This passive system permits cooling without energy expenditure.

• Accumulation of rainwater. The rainwater will be collected for cooling and for watering plants on the green roofs and green facades.

• Three-dimensional greening extends on all building and urban surfaces achieving a high green coverage ratio with green roofs, green terraces, green facades, green patios and green pavement.

• Collection of solar energy. On the curved solar canopies, a series of photovoltaic panels will capture energy for the energy of the buildings.

Shaft ventilation and natural lighting

Full height skylight atria achieve natural lighting and ventilation through chimney effect and ensure a distribution without corridors. By giving the atria multiple roles, the project optimizes the surfaces. The project skylight atria have extensive roles and are key for the energy performance of the buildings. They are all lit in overhead light and can open in their upper part. The multiple roles of the atria are:

• Contain the vertical public circulation (helical staircases) of the different buildings; This role is particularly important in the AI Experience Centre which aims to accommodate a large audience by offering varied routes and experiences. 

• Maximise the natural light and contribute to reducing the energy consumption for lighting by 50%. 

• Enhance natural ventilation in summer to reduce cooling energy consumption by about 20%. 

• Use passive solar gain in winter (for the atrium at the south-east corner of the AI Experience Centre) and help reduce energy consumption for heating.

Shading and positive energy 

French Dream Town Northern Part is positive energy through 5000 m2 of solar PV canopies. It produces 220% of its energy consumption, making the whole 2 ha French Dream Town site a zero-energy development. The positive-energy strategy comprises three levers:

• Reducing the demand through energy-efficient forms. The design minimises primarily cooling energy loads. The project atria with skylights and the green roofs and terraces are all part of the green strategy. They make it possible to obtain positive energy buildings using photovoltaics. All areas within the buildings are less than 6 m from a natural light source achieving a 100% Passive Volume Ratio (the volume that can benefit from natural light and ventilation and from solar gains). The atria with skylights ensure that no corridors occupy a significant part of the floor areas with long luminary operation hours. 

• Reducing the demand through energy-efficient systems. Through holistic integrated planning of multiple energy saving measures, the most feasible ones were combined into one proposal.

• Supplying the remaining energy loads with renewable energy. The implementation of PV modules generates renewable energy generation on-site and makes the development energy positive and carbon neutral.

Integrating systems with smart cities management  

French Dream Town in Hangzhou is rethinking how to ‘live smart’ in a digital era. It is an experimental smart city that provides living labs as an essential tool to facilitate urban innovation. It innovates through an experimental and people-centric approach. Its goal is to achieve holistic sustainability. It is designed as an integrated urban area with improved navigability, tighter-knit community, better public realm, and that is less resource intensive. It combines the urban landscape and nature, digital technology, human sciences and art. To achieve this, several strategies and smart-oriented systems are implemented to manage several aspects of urban life. The use of smart technologies and digital connections are also part of the common vision for Green and Thriving Neighbourhoods.

French Dream Town focus is on connecting and integrating information systems that used to operate independently. A smart city control centre and platform are therefore built to integrate systems and reap synergies between them. French Dream Town’s advanced infrastructure combines ICT with infrastructure in transport, safety, and built environment. It aims at realising the full potential of IoT for managing city systems. It utilises a vast array of sensors and actuators. They are connected by networks to computing systems. This allows monitoring building energy, the consumer enhanced experience, the connected objects and machines in industrial production processes. It will comprise networks of connected devices and sensors, smart applications and data analysis capability, with cloud Artificial Intelligence, IoT/AI/embedded machine learning, green blockchain, smart energy storage, WI mesh networks. 

French Dream Town successfully addresses a set of system issues that are critical for interoperability. It captures the extensive benefits of interoperability across multiple settings such as homes, offices, factories, worksites, retail environments, cities, vehicles, and the outdoors. Below, the systems composing ‘City Brain’ are displayed. 

French Dream Town has leveraged its multiple urban data flows integration platform to design innovative solutions in smart energy, smart grid technology, smart solar technology, and Home Energy Management Systems. The district has sensors/actuators. They communicate on a local wireless loop connecting the buildings and production assets to the cloud and the French City Brain. This will create value for the developer – CAPEX – by avoiding grid reinforcement/oversizing costs, reducing infrastructure footprints, and differentiating services. This will also produce value for the facility manager – OPEX – by diminishing network connection fees, guaranteeing local green energy supply.

Lessons Learnt

French Dream Town in Hangzhou demonstrates how it is possible to plan and design a zero-carbon development with solutions that draw from the context and enrich the existing historical, architectural, and social urban fabric. Moreover, the case study shows how it is possible to maintain a connection to the local culture while implementing cutting-edge sustainability concepts to reduce energy consumption. Finally, the project is an example of how smart-oriented solutions can optimise the management of systems through their integration, creating a network managing diverse resources and different aspects of urban life. Hangzhou French Dream Town experience in generating a sustainable creative neighbourhood – both through design, net zero integrated systems and creative digital economy highlights lessons learned that can help shape urban development strategies.

• Local economic development: An important lesson for any city like Hangzhou with a rich cultural heritage is to preserve and cultivate its creative and cultural heritage when designing new neighbourhoods.

• Urban transformation: Hangzhou’s government has multiple roles in ensuring that its neighbourhoods flourish and attract creative talent and has selected French Dream Town to act as a catalyser. 

• Social inclusion: Hangzhou French Dream Town fosters synergies between creative areas and associated educational centres whose impact is felt beyond the academic sector, especially in urban transformation and generating creative talent. In French Dream Town, creative community growth hinges on multi-sector partnerships.

Footnotes

[1]Mulas, Victor; Miki-Imoto, Haruka; Jain, Vibhu; Tawara, Shoko; Kadono, Michiko; Wyne, Jamil (2021). Kyoto A Creative City: Leveraging Creativity for City Competitiveness and Inclusive Urban Transformation. World Bank, Washington, DC. © World Bank.