SHELLTER: Sustainable Architecture for an Underwater Live, Work, and Play Habitat

Project Name: SHELLTER

Competition: EHC - Pacific

Recognition: Shortlisted Entry EHC - Pacific

Project By: Mauricio H. de la Cueva, Daniela Miyoko Yesaki Serrato, Sofía Contreras Sánchez, Francisco Canche

A New Vision for Sustainable Architecture Beneath the Ocean

SHELLTER is a speculative underwater habitat that rethinks the future of living through the lens of sustainable architecture. Designed as a modular dwelling for the Pacific Ocean, the project proposes a shell-like residential unit capable of supporting the live, work, and play triad in a submerged environment. Rather than treating the ocean as a hostile frontier, SHELLTER imagines it as a habitable ecological territory where architecture, marine systems, energy production, food cultivation, and human wellbeing can operate together.

The project is located near Carnegie Ridge, a tectonic extension between the Galápagos Islands and Ecuador. This position is significant because it offers climatic stability, abundant marine biodiversity, high solar exposure near the equatorial line, and access to hydrothermal activity. The design uses these environmental conditions as active architectural inputs. Instead of depending entirely on imported infrastructure, SHELLTER proposes an underwater community that draws energy, food, water, and oxygen from its immediate marine context.

As a shortlisted entry of EHC - Pacific, SHELLTER by Mauricio H. de la Cueva, Daniela Miyoko Yesaki Serrato, Sofía Contreras Sánchez, and Francisco Canche offers a provocative question: can sustainable architecture extend beyond land and become a framework for long-term underwater habitation?

Inspired by the Seashell as Structure and Shelter

The visual identity of SHELLTER is rooted in the form of a seashell. Its round and spiral geometry creates an immediate relationship with the marine environment, allowing the habitat to feel native to the ocean rather than imposed upon it. The shell form is not simply symbolic. It becomes a spatial, structural, and environmental device.

The proposal begins with a basic cylindrical geometry, one of the most effective forms for resisting underwater pressure. This basic volume is then divided into levels, reduced in section, and modified with platforms to enhance privacy. A central vertical circulation core connects the floors, while carefully positioned openings bring controlled natural light into the interior.

The result is a compact but layered underwater dwelling. Its spiraling form encourages movement, physical activity, and gradual transition between different atmospheres. The design avoids a flat, mechanical reading of underwater living and instead creates a spatial journey through work, social life, rest, and contemplation.

Site Strategy: Carnegie Ridge as an Ecological Anchor

SHELLTER is positioned at Carnegie Ridge, located between the North and South Poles and near the equatorial Pacific. This location provides several advantages for underwater sustainable architecture. The equatorial line receives high solar radiation, while the humid oceanic climate remains relatively stable throughout the year. The surrounding biodiversity offers opportunities for symbiotic food systems, and hydrothermal vents provide the possibility of energy production through thermal conversion.

The project treats this remote location not as isolation, but as protection. The distance from inhabited land gives users a sense of safety while creating a controlled, self-sufficient underwater habitat. In this context, the ocean is not just the site. It becomes the life-support infrastructure.

Internal Organization: Live, Work, and Play Underwater

The central design ambition of SHELLTER is to support the live, work, and play triad. The interior is organized as a vertical sequence of atmospheres, with each floor offering a different level of social interaction, privacy, and connection to the sea.

The lower areas accommodate circulation, gathering, and more active shared functions. As users ascend through the spiral structure, the spaces become quieter and more private. Bunk rooms and personal areas are located in the middle zones, creating a calm domestic environment. At the top, the program becomes meditative, using visual connection to the ocean as a psychological and spatial release.

This vertical transition is important for underwater living. In a submerged habitat, the lack of conventional outdoor space can affect mental and physical wellbeing. SHELLTER addresses this by using circulation as exercise, portholes as visual relief, and changing floor atmospheres as a way to prevent monotony.

Water, Oxygen, Food, Energy, and Waste as Architectural Systems

SHELLTER is designed as an integrated environmental machine. Its sustainable architecture strategy is built around five major systems: potable water, oxygen, food, energy, and waste.

The potable water strategy uses reverse osmosis. A desalination process is incorporated into the porous shell of the structure, filtering salt ions through a semipermeable membrane and turning seawater into drinkable water. This allows the habitat to reduce dependence on external supply chains.

The oxygen system is based on an internal greenhouse. Indoor plantation areas provide food and clean oxygen for users while creating a controlled atmosphere within the module. This greenhouse system allows crops to grow independently from exterior conditions.

Food production is supported through underwater farms. Seaweed such as kelp, which is abundant in the ridge environment, becomes a rich food source for settlers. These farms operate in symbiosis with surrounding marine life and contribute to the broader ecological loop.

Energy is generated through a thermoelectric converter. The system converts hydrothermal fluids from vents near the Galápagos Islands into hydrothermal energy for each home. By adapting to tensioned lines and seabed anchors, each module can connect to a larger underwater energy network.

Waste is redirected to underwater farms and composting systems. Instead of treating waste as an external problem, the project folds it into a recycling loop that supports both marine biodiversity and human settlement.

A Modular Habitat Designed for Scalability

One of SHELLTER’s strongest ideas is its modular growth system. Each dwelling connects to other units through underwater farms and tensioned lines. Every module has three tensioned cables that anchor the structure to the ocean floor. These lines end in farms, allowing each home to share food and energy with neighboring units.

The community is planned horizontally, responding to strong ocean currents and seabed conditions. The diagrams suggest that the system could grow to more than 100 units, creating a dispersed underwater settlement rather than a single isolated object.

This approach gives SHELLTER a larger architectural relevance. It is not only a standalone underwater pod. It is a prototype for community-based marine habitation, where each unit contributes to a wider network of resources, energy, food, and ecological exchange.

Material and Structural Logic

The module’s exterior shell is designed to resist underwater pressure while maintaining a sense of interior normalcy. The project references the logic of pressure hulls used in submarines, where curved geometries help distribute force efficiently. The basic cylindrical form is transformed into a rounded spiral volume, balancing pressure resistance with spatial identity.

The habitat is anchored through tensioned lines, reducing the need for deep excavation or extensive seabed intervention. This minimal-contact foundation strategy supports the project’s sustainable architecture agenda by limiting disturbance to the ocean floor.

The shell-like form also reduces surface impact. Rather than spreading across the seabed, the module rises vertically, preserving more of the surrounding marine environment. This makes the habitat compact, legible, and adaptable to future underwater settlement clusters.

Natural Light and Psychological Wellbeing

One of the most important challenges in underwater architecture is psychological comfort. Without daylight, open sky, outdoor movement, or broad social contact, underwater living can quickly become claustrophobic. SHELLTER responds through portholes, skylight-like openings, and controlled views into the marine environment.

The portholes act as both visual anchors and environmental devices. They connect the interior to the surrounding ocean, allowing users to experience marine life, movement, and depth. The top-level meditation space uses this relationship most strongly, turning the ocean into a contemplative interior horizon.

The project also uses vertical circulation to maintain daily physical activity. Instead of relying only on mechanical life-support logic, SHELLTER builds wellness into the spatial organization itself.

Juror Comment and Critical Reflection

Juror Begoña Fernandez-Shaw noted that although the idea of a shell-shaped living unit is attractive, the proposal risks becoming too isolated for long-term habitation. The comment also points out that the interaction between units needs further development, particularly in terms of colony behavior and social connectivity. The portholes were also seen as insufficient in supporting the broader spatial experience.

This critique is valuable because it identifies the central tension of the project. SHELLTER is visually strong and environmentally ambitious, but its success as a long-term habitat depends on how convincingly it can operate as a community rather than as a set of isolated objects.

The project already gestures toward this issue through its modular diagram, shared underwater farms, energy networks, and horizontal settlement strategy. However, a more developed version could strengthen the links between modules through communal interiors, shared docking points, collective workspaces, underwater circulation corridors, or social nodes where residents can gather beyond the private unit.

In this sense, the juror’s comment does not weaken the project. It opens a clear path for further design development. SHELLTER’s next evolution could move from individual sustainable architecture to collective underwater urbanism.

SHELLTER as Speculative Ocean Urbanism

SHELLTER sits between architecture, marine technology, ecological design, and speculative urbanism. It does not simply ask whether humans can survive underwater. It asks what kind of spatial culture could emerge if underwater life became possible.

The live, work, and play triad is central to this ambition. The proposal understands that a habitat is not only a protective container. It must provide social life, privacy, productivity, health, food, water, energy, and emotional connection. In the ocean, these requirements become even more complex. Every window, stair, farm, cable, wall, and environmental system must perform with greater precision.

By using a shell-like form, SHELLTER creates an architectural language that feels connected to its marine setting. By using modular systems, it proposes a framework for growth. By integrating food, oxygen, energy, water, and waste cycles, it advances a vision of sustainable architecture that is not decorative, but operational.

SHELLTER is a bold exploration of underwater sustainable architecture. Its strength lies in the way it combines ecological systems with an emotionally legible form. The seashell becomes more than a metaphor. It becomes a pressure-resistant dwelling, a vertical domestic landscape, a life-support system, and a unit within a possible underwater community.

The project’s most compelling contribution is its attempt to make underwater living feel less like survival and more like inhabitation. It imagines a future where homes can exist below the surface while remaining connected to food production, clean water, energy, oxygen, biodiversity, and human wellbeing.

As a shortlisted entry of EHC - Pacific, SHELLTER by Mauricio H. de la Cueva, Daniela Miyoko Yesaki Serrato, Sofía Contreras Sánchez, and Francisco Canche expands the conversation around ocean habitats and sustainable architecture. Its next challenge is to deepen the social life between units and transform its modular system into a true underwater colony. Even so, the project offers a powerful architectural proposition: beneath the ocean, a shell can become a home.