Closed cities have become the shorthand for futuristic settlements in science fiction. These are self-sufficient habitats that contain all necessary infrastructure, including energy production, food production, waste management and water supply.
In 1969, the architect Paolo Soleri came up with the concept of ecology, a comprehensive term that combines architecture and ecology, and tried to combine architecture with ecological philosophy. A year later, Soleri began working in the experimental town of Akosanti in the United States, presenting his concept.
Soleri’s concept inspired science fiction’s vision of the city of the future: a unified habitat where people live and work from the comfort of a building. Film examples include Dredd’s massive high-rise building (based on the comic book character Judge Dredd) and skyscrapers, but there are few details on how they work.
Science fiction, in turn, could inspire some real-world options. Saudi Arabia’s proposed The Line is billed as a giant smart city capable of housing 9 million people in a building 200m (660ft) wide, 170km (105mi) long and 500m (1650ft) high. The line will be powered by solar and wind turbines but will not be completely self-sustaining as residents will still need food and other supplies that must be provided from outside sources.
Some structures like ecology already exist. Antarctic research bases, for example, are relatively self-sufficient communities, largely due to their remote location. The environment also means that they must be self-sufficient. About 3,000 researchers and support staff work at McMurdo Station. However, the station still requires a large supply of food and fuel each year.
Other structures designed to be as self-sufficient as possible include aircraft carriers, nuclear submarines and oil rigs. They have all the accommodation and work space required by the crew, albeit for short-term use. An aircraft carrier needs resupply every few weeks, and a nuclear submarine can stay submerged for up to four months. However, these are not particularly habitable places. Submarines, in particular, are cramped and smelly, can share sleeping quarters, and due to lack of sunlight, crew members need to take vitamin D supplements.
But can we really build an ecology? The size of this structure requires a huge foundation to support its weight. “You can build anything within reason,” says Monika Ansperger, structural engineer at BSP Consulting. “The load will be huge, but nothing is impossible. Building the foundation for it will only cost more.”
A more serious problem with building height is the effect of wind. For a typical house, the wind load is irrelevant, but for huge towers such as the Burj Khalifa in Dubai, wind flow and eddy must be taken into account. A whirlwind is an effect caused by wind hitting the surface of a building, creating a low pressure area on the opposite side, which then swirls to fill it. It is this vortex action that causes tall buildings to sway in high winds.
Rocking effects can range from drink ripples to structural collapse. The Tacoma Narrows Bridge in Washington DC collapsed in 1940 when strong winds caused increasingly higher frequency vibrations (rapid traffic) on the bridge, so strong that the bridge was torn to shreds. The effects of eddy currents can be mitigated by using tuned mass dampers (a device that reduces vibration) to reduce movement and by designing structures that disrupt wind flow.
“One way to mitigate eddy currents is to reshape buildings as they rise,” said Adrian Smith, architect of many large buildings, including the Burj Khalifa. “If you don’t change the shape of the building, this vortex can build up on its own and create waves of motion. They synchronize with the structure of the building and cause gradual destruction.”
Therefore, rather than constructing a curvilinear building as a shear wall structure, as proposed in Dredd, it can be built to disrupt the flow of the wind, such as in a stepped structure, as in ancient Mesoamerican structures.
See an image of architectural projects like Line, imagine a group of people happy to live and work under the same roof (Source: Credit: Andrey Onufrienko/Getty Images)
Another key issue is energy production. Renewable energy technologies such as solar panels and wind turbines can be easily installed outside the ecosystem, but on their own are unlikely to provide a complete energy solution. Since they are only valid at certain times, backup generation and storage systems will be required in case of a shortage.
Nuclear reactors are a possible alternative solution for energy production. Small Modular Reactors (SMRs) are small versions of advanced nuclear reactors built in chemical plants that provide a compact and efficient source of power. Small and medium sized reactors claim some advantages over larger reactors in terms of increased safety and prevention of nuclear material proliferation. However, as with all nuclear reactors, nuclear waste management and storage is a challenge. Alternatively, fusion reactors would be safer and provide cleaner energy, but current designs are neither compact (one of them, Iter, is expected to weigh 23,000 tons) nor financially viable, since no more have yet been produced. energy than they use.
Food production also needs to be considered. Traditional agriculture is not practical inside the building. You can use vertical hydroponic farms, which will also provide a natural way for air to circulate. However, the required lighting increases the need for energy, and the lack of space can make it difficult to produce enough food.
It seems plausible that the ecology depicted in Paolo Bacigalupi’s novel Waterjet Cutting uses a series of filter ponds to reuse water. However, in any recycling system, losses are inevitable. The International Space Station (ISS) processes about 3.6 gallons (17.3 liters) of water per day, including urine and sweat, but still requires a regular supply of fresh water every few months.
Not everyone sees the future of high-rise buildings. In 2021, China banned the construction of new buildings over 500 m (1,650 ft) and imposed strict restrictions on buildings over 250 m (825 ft).
However, it is necessary to adapt to the growing population of the planet. The constant horizontal expansion of the city by building on new lands cannot continue indefinitely. This supports the argument for moving up, creating vertical cities. “Cities are expanding rapidly, from 1 to 10 million people,” said Anthony Wood, director of tall buildings and vertical urban planning at the Illinois Institute of Technology and chairman of the Council on Tall Buildings and Urban Habitat. “They cannot grow horizontally. because it’s not sustainable. , due to the consumption of land and energy required to build and operate a horizontal city. It will go vertical. (Learn more about whether we are running out of space.)
Could exposure to nature and light lead to class divisions in these future settlements? (Photo: Yuichiro Chino/Getty Images)
Instead of separate towers, the buildings could be connected by land bridges, creating green spaces between them. However, as the land bridge network continues to grow upwards, it is possible to obscure the lower levels and make the higher levels more desirable, resulting in a structured hierarchy.
“I see cities expanding vertically near transport zones, and I definitely see them expanding horizontally as well,” Smith said.
As the effects of climate change become more apparent, the materials used to build cities are likely to change. Carbon emissions from the cement industry exceed those from the aviation industry. An alternative building material could be solid wood: an engineered product made from laminated boards glued together. “The energy needed to produce a large amount of wood is only a fraction of the energy needed to produce the same material from steel or concrete,” Wood said. “When it produces itself, it captures carbon from the atmosphere.”
While it is theoretically possible to build an ecology, at least from a structural point of view, creativity is required to ensure the necessary energy, food and waste production systems are sustainable. Critics say it’s hard to see how ecology can become economically viable in the near future. There’s also the argument that if the apocalyptic events make the outside world uninhabitable, then permanently living in a closed area will be unpleasant, although it’s comforting to know that this is possible.
“I would never say something that cannot be built,” concludes Ansperger. “It can be built, but it takes a vision and a need.”
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