Mar 24
The future of cities
What first comes to my mind are very tall skyscrapers connected by suspended bridges and large hanging gardens.
New technologies will enable us to make even taller buildings than those of today, capable of accommodating thousands of people: “vertical cities” where it will be possible to live, work, have fun, shop and go to the cinema. These new constructions will make extensive use of graphene, carbon foam, transparent concrete and other super-light and ultra-strong materials.
Optical fibers and electrical cables will run under our streets, while parking lots will all be underground and automated: the vehicles are left by the owner on a platform that will take care, with a mechanical arm, to “park” the car in the first available space.
A city capable of managing resources in the most efficient and ecological way possible, with vertical farms and woods, with buildings covered with solar panels, capable of collecting rainwater for shared use and cleaning air; Ideally they would be completely self-sufficient structures, almost resembling a living organism.
But let’s delve more into the topic.
- Lighting
Glowee, a Parisian startup, plans to use bioluminescent bacteria derived from a particular type of squid as a possible substitute for traditional street lighting.
The bacteria are contained in transparent containers along with the oxygen and glucose they need.
The advantages are numerous: they produce less light pollution, do not consume electricity and therefore contribute to reducing greenhouse gas emissions, do not require additional infrastructures, and the shell that contains the bacteria is transparent during the day and can take any shape. They could be the bilboards or the street lamps of the future.
Another option is the one developed by a group of researchers from Barcelona, which consists of trees modified with a gene that codes for bioluminescence in jellyfish. They could produce light while also keeping the air clean.
- Roads
Electreon is an Israeli start-up that’s developing a technology capable of recharging electric vehicles while they are in motion, thanks to a series of coils under the roads that charge cars by induction. Thanks to this innovation, even heavy electric vehicles, which would require large and expensive batteries, become economically feasible.
John Read and his team, on the other hand, are the creators of a new type of asphalt which, when laid on the ground, interacts with the air itself and absorbs harmful gasses, such as sulfur dioxide, nitrogen oxide and carbon monoxide, with an efficiency 40% greater compared to traditional asphalt.
A company called Integrated Roadways is also developing the smart pavement, an intelligent road, whose inner layers are composed of concrete slabs with optical fibers and embedded digital tools. The fibers detect pressure, speed and position of the vehicles, and use them to infer what’s happening over the roads. They can also call for help when they sense an accident, among other things.
Some Dutch scientists have also invented a method that allows roads to repair themselves, thanks to steel wool fibers embedded in the asphalt itself. When electric current goes through the fibers, they dissipate heat capable of melting tar and healing those cracks which, if left unchecked, would cause holes and bumps. This technology could double roads’ longevity and can also be used to charge electric cars by induction.
- Buildings
Cement is perhaps the most used material in construction, mainly because it is cheap. But it requires large amounts of energy to produce and is responsible for 8% of carbon emissions alone.
A bizarre alternative could be buildings made of synthetic bones. It sounds like a crazy idea, but bones are actually very strong for their size and weight (a piece of bone the size of a sugar cube can withstand a ton and a half of pressure) and thanks to their porous structure they are also very elastic and resistant to stress. Bones are mailny made up of collagen, calcium and phosphorus. To produce them artificially, a mold must be immersed in a solution of collagen and calcium and then in one of phosphate and collagen anions, repeatedly. The only problem is that it is currently very difficult to synthesize collagen, but if it were possible to obtain it artificially and not from animals, this would be a very attractive alternative.
Another construction material, that is both ecological and economical, is Ashcrete, an alternative cement made with the ashes of incinerated plants, or the Breath Brick, a brick made of regular concrete but able to absorb and clean the air that enters the building. It does so by creating a vortex of air in a special structure inside the brick, which causes polluting particles to settle inside the wall, letting clean air pass through. They are able to capture up to 30% of pollutants and almost all the larger particles, such as dust.
Another very interesting idea is that of skyscrapers where water, instead of being pumped to where it’s needed, can be harnessed through a net at the top of the building when clouds pass through it, in order to get free water and even save electricity.
- Graphene
A material with astounding thermal, mechanical, optical and electronic properties: density equal to half of aluminum, tensile strenght 50 times higher than steel, resistant to large variations in PH and temperature, practically transparent, very thin, very light and able to conduct electricity and heat with enormous efficiency.
Here are just some possible uses of the material:
- Very thin solar cells capable of converting solar energy into electrical energy with an efficiency up to 60% higher than that of the best solar panels currently on the market.
- Extremely light aircraft and that can therefore also be electrified.
- Batteries with storage capacity and charging times that are unthinkable today.
- Innovative hydrogen storage systems in graphene lattices. They could be used to fabricate mobile electricity generators, that would be powered by hydrogen extracted from air.
- Huge breakthroughs in consumer electronics: folding computers, smartphones and tablets, with ultra-thin and resistant displays. Electronic devices could be printed directly on clothes, thus becoming totally wearable. The secret lies in graphene ink: an infinitely thin ink jet will project circuits on any surface.
- Extremely fast Internet connection cables.
- Very low consumption transistors for portable applications and that would be able to dissipate heat more efficiently.
- By covering copper with a thin layer of graphene it is possible to decrease the resistance of the cables used to connect the transistors inside the processors and prevent the performance of the device from collapsing as size decreases.
- Its molecular structure allows you to create holes of any size on its surface, thus allowing for very small equipment with zero energy cost to filter and desalinate water. Even bolder applications would be using a sheet of graphene with holes to sequence DNA fragments very quickly.
- Applications in the textile world: fabrics with antistatic properties, highly conductive, that shield from electromagnetic waves and are also able to change temperature.
- Even edible graphene: the latest discovery about graphene is that it is easily printable on food. American researchers have succeeded in etching edible circuits with a laser, creating a “foam of tiny graphene flakes” on the surface of food, paving the road for ecologically labelled meals.
- With graphene contact lenses it will also be possible to see in the dark. Currently used in infrared cameras, they can be used to identify chemicals dispersed in the environment or to monitor blood flow within the human body.
- Graphene has also the potential to affect the pharmaceutical industry, enabling the targeted administration of pharmacological components at the cellular level or the creation of bionic implants, such as artificial retinas. Graphene nanoparticles are non-toxic up to a concentration of 50 µg / ml. This means that, at low doses, they are safe for biomedical applications.
- Fingerprint sensors that exploit graphene’s high conductivity for lightining fast reaction times. Such a fast sensor could be used to open cars, replacing the classical keys, or to make “smart guns” a reality (fingerprint sensors on the trigger would allow the gun to fire only if held by the owner).
- Since graphene is practically waterproof, a graphene-based paint coat could be used to eliminate corrosion and rust. Researchers have even shown that glass or copper plates coated with graphene paint can be used as containers for highly corrosive acids.
- Electronics that can integrate with biological systems: It may be possible to implant graphene gadgets that can read the nervous system signals or speak to cells. This could help doctors monitor the human body or could even be used to adjust biological systems for optimal health.
- Thanks to the development of a new graphene-based electrode technology, a kind of incandescent “wallpaper” has been developed, which provides a more pleasant and dimmer light than light bulbs, and that is also more energy efficient. In short, illuminated walls similar to those of “Tron” could soon replace light bulbs.
- Chemical chimeras are also being developed: compounds of graphene and other materials, such as a speiderweb or a diamond hybrid. A graphene slime can “hear” the footsteps of a spider, while graphene oxide has already been used for holographic displays.
- Also 3D spongy constructions were made using graphene sheets, that results in a material 10 times harder than steel and significantly lighter. And it is for this precise combination of strength and lightness that graphene is indicated as a possible material for the realization of science fiction ideas such as space elevators and solar sails. However, we still have to solve the question of the reliability of a 36 km long cable, the minimum length for a space elevator.
- It can surprisingly be tuned to behave as an insulator, or even as a superconductor at room temperature. Put simply, the same material can block the flow of electrons or conduct an electrical flow without any resistance. And as if that weren’t enough, graphene nano-tapes can be used as logic gates in quantum computers, and would greatly accelerate their development. The videos below delve deeper into the topic.
https://en.wikipedia.org/wiki/Graphene_nanoribbon
- Preventive measures
Polish designers Damian Granosik, Jakub Kulisa and Piotr Pańczyk have developed an origami-inspired skyscraper that can be “folded” and transported to areas affected by natural disasters. It is called Skyshelter.zip and offers a large usable surface, that at the same time is compact, easy to transport and settable in a short time. Skyshelter.zip can be deployed instantly, even on unstable ground just by anchoring the base supports to the ground and inflating the structure with helium balloons. The building also produces clean energy for its own operation.
When the wind hits a flat rectangular surface, the airflow splits into two large eddies that move around the building structure putting it under stress. This doesn’t happen with a newly designed building with a helical structure similar to a screw, that channels the air in its curves and breaks the two large eddies into many smaller eddies that exert less stress on the structure. This, in addition to making skyscrapers safer, limits the influence of the wind during their construction. A similar idea is applied to the Sky Mile Tower in Tokyo, with a six-sided structure that dissipates the force of air and water that is thrown at it.
Technologies similar to those just described would make possible skyscrapers built near or directly on water, and able to withstand typhoons and tsunamis.
An alternative proposal is that of a series of connected buildings, which would constitute the “pillars” of a structure that lets wind and water pass through its cavities. The buildings would be connected by Sky Bridges, to facilitate transport.
The idea of a concrete that repairs itself is also interesting. It is obtained with a bacterium, sporosarcina pasteurii, which synthesizes calcite. These bacteria are placed in biodegradable plastic capsules mixed into cement, with calcium lactate as nourishment. When cracks form, infiltrated water dissolves the capsule, releasing the bacteria. Those in turn, begin to feed on the calcium lactate and to produce calcite as a byproduct. Calcite is what finally binds to cement and fills its crack. This can restore up to 90% of concrete’s original strength. This technology is still expensive at present time, but in the future its price could go down, and capsules like these could be directly sprayed on buildings.
In addition to the most advanced anti-seismic measures, skyscrapers could benefit from ViBa, a technology that is as recent as it is simple: a central mass held in place by springs inside a container that absorbs a large part (90%) of the specific vibrations that would damage buildings. Great for constructions that cannot be modified such as buildings with historical and cultural value, and can also protect more than one structure at a time.
- Road Network
The city could be composed of a square grid globally, where the square units’ streets follow a cul-de-sac pattern. This last road pattern was initially conceived to shelter from streets increasingly full of noises and traffic. The cul-de-sac scheme uses resources efficiently, saving on concrete, and given the low traffic, the internal roads can afford to be narrower, while the main ones can be wider and support very fast cars, thus reconciling the need for a fast-paced, high-speed grid outside the housing units, with a quieter and safer one inside. It’s advisable to have a square grid structure over long distances to allow faster transit of means of transport. The cul-de-sac pattern tends to increase distances, especially for pedestrians and cyclists, which is why it is convenient to use them only for the housing units, which are small in size.
The stores would be along the busiest streets, on the outer edge of the “residential squares”, while parks, bookstores, squares, schools, parking lots and residences would be placed along the quiet inner streets. I imagine the structures inside the “squares” as green oases of tranquility made up of buildings somewhat similar to these:
The larger outer roads may also be traversed by animal (and human) flyovers such as those used today in the Netherlands.
The internal cul-de-sac streets, on the other hand, could only have T-intersections, since they cause almost eight times less accidents than classic intersections and would make housing “squares” even safer.
- Feeding
Vertical farms could, and should, replace traditional agriculture. Plants grow indoors on multiple floors, independently from the external climate and in less space than would be needed, also allowing to control the flow of pesticides and fertilizers much more efficiently. The system can be hydroponic, with plant roots submerged in nutrient-rich water, which would require up to 90% less water than traditional methods, or aeroponic, where plant roots are exposed to a mist mixed with nutrients. This last method even requires 70% less water than the hydroponic system. And since vertical farms can fit into cities, there are far fewer emissions for transporting the final product. The only disadvantages are the electricity consumption for pumping water, lighting the plants and monitoring them.
The meat of the future could grow in labs. Unlike the current method, it does not require slaughtering animals and using resources, such as water, land, and food that could be used to feed humans, in extremely inefficient ways. Synthetic meat is made starting with stem cells, painlessly obtained from animals, which are then grown in a solution rich in amino acids and carbohydrates. The result are fibers that when put together form the actual muscle tissue. In the future it will be a solution not only environmentally and ethically correct, but also economically advantageous. The price of a lab-grown Hamburger has already dropped from $325,000 to just $11 over the span of a decade. Still more expensive than one of McDonald’s sandwiches but a step in right direction anyway.
- Transportation
I take it for granted that the vast majority of the cars of the future will be both electric and self-driving. Just these two improvements bring many benefits: less environmental and noise pollution, and a drastic decrease in traffic and accidents. From a design point of view, they could be longer (perhaps 6-seater) and ergonomic. Probably lighter and with integrated solar panels on the roof that can partially power them.
NEXT Future Transportation Inc. is an Italian start-up born from the idea to decongest city traffic with an intelligent transport system based on self-driving modular electric vehicles. In the not too distant future, you’ll just need to call one of these four-wheeled pods that will take you to one of the main routes of the city. There it’ll connect on the run to other modules with an automated coupling mechanism. Once connected, the pods in the chain will effectively form a single vehicle, similar to a bus. Thanks to the versatility of the NEXT modules, public transports could become as flexible and widespread as a taxi and at the same time as efficient and functional as a private car transport.
In China, the Transit Elevated Bus was just tested for the first time. It’s a bus that is able to pass over traffic to quickly bring its passengers to their destination. It can host up to 300 passengers and climb over cars and trucks with its long “legs” anchored to rails. This vehicle could represent a turning point for public transport in cities affected by increasingly congested traffic. Its development promises great advantages: It could completely replace subways and its installation is also far cheaper.
The long-awaited and fantasized flying cars could become a reality, even if, for logistical reasons, safety, and noise pollution, their use could remain limited. Maybe as a substitute for ambulances, police vehicles and taxis.
Hyundai and Uber’s Personal Air Vehicle (PAV) is an example of an air taxi. It has two rotors in the tail and 10 on the wings, arranged on either side of an egg-shaped cabin. All rotors have variable inclination, to allow vertical take-off and landing like a helicopter, and horizontal flight like an airplane. It’ll only take 5–7 minutes to recharge, and it has a range of 100 kilometers. It can carry five passengers plus the pilot at a cruising speed of 180 mph, and can reach an altitude of around 300–600 meters.
UAM, acronym for Urban Air Mobility, is the land hub that will allow flying cars to take off and land.
- Electricity production
In the last sixty years a considerable theoretical and experimental effort has been made to develop nuclear fusion for civil rather than war purposes, i.e. to generate electricity in a much more efficient way and with almost no damage to the environment. Nuclear fusion is probably the technology with the greatest potential to solve humanity’s energy problem.
The main problem is the difficulty of achieving a reactor with a positive energy balance. To date it has not yet been possible to build a reactor that constantly produces more electricity than it consumes.
At the moment the most advanced fusion reactor is the ITER, an international cooperative project between the European Union, Russia, China, Japan, United States of America, South Korea and India.
Kilopower, on the other hand, is a small and light nuclear fission system capable of supplying up to 10 kilowatts of electricity, enough for several medium-sized families, continuously for 10 years. Four Kilopower units would provide enough power to power an entire outpost. It was developed to produce energy from nuclear fission with a stable and safe system in any environment.
The reactor core is uranium-235, similar in size to a roll of toilet paper, surrounded by beryllium oxide walls, which deflect neutron emissions and deflect their energy towards the core (to minimize gamma radiation that could compromise on-board electronics). Control of the nuclear reaction is provided by a single rod of boron carbide, a neutron absorber that inhibits the nuclear reaction.
Passive heat pipes filled with liquid sodium transfer the heat generated by the core to one or more Stirling engines, that turn it into electricity.
The reactor is designed to be safe in a wide range of environments and scenarios. Several feedback mechanisms are employed to prevent the melting of its core, and it’s been demonstrated that it could successfully handle many types of failures.
- Various technologies
A team of German scientists from Freiburg have developed a new process to extract germanium, a semimetal widely used in electronics and chemistry, from the earth without too much effort. The innovation consists in using plants to do the “dirty work” through “phytomining” (phytomineralization). Metals are basically accumulated in high concentrations by plants with a high biomass content. Some of these plants are natural hyperaccumulators, but this property can also be induced. Exploiting plants’ ability to absorb substances from the soil will allow to replace current methods of mining of metals (like gold, copper or germanium) with more environmentally sustainable ones.
Economically speaking, this process is also very efficient, because metals’ extraction can take place while the plant biomass is transformed into biogas inside already exsisting biodigesters, found in biodiesel production facilities.
“Biomining” is based on a similar principle. It’s a technique of metals’ extraction that utilizes prokaryotes or fungi. These organisms secrete several compounds that collect metals from the environment and bring them into their cells. Some microbes can use stable metals like iron, copper, zinc and gold, as well as unstable atoms like uranium and thorium. Biomining is a much greener technique than typical mining, that releases many pollutants. These bacteria could one day mine metals, purify gold, clean up oil spills and much more.
Think of how much paper you could save if you could read from a screen, from a thin and practical electronic “sheet”. It is called an electro-fluidic display and is made up of two thin plastic films. The first features a grid of small cells, each of which corresponds to a pixel and is surrounded by a “moat” filled with air or oil. The central part of the cell houses a small cavity that contains a droplet of aqueous pigment. A second transparent film is applied over the first.
At “rest” the pigment remains inside the cavity, small enough to be invisible to the naked eye, so that the display reflects light like a white sheet. When voltage is applied between the two films, the pigment comes out of the cavity and colors the entire cell, making it visible. And when voltage is no longer applied, the pigment re-enters the cavity.
The electro-fluidic display has many advantages: the contrast and the colors are exceptionally close to those of real paper, and since it doesn’t emit its own light, an excellent performance is guaranteed even with sunlight.
Furthermore, efficiency is much higher than normal displays’, since electronically controlling the drops of the pigment requires less energy than emitting light. And electro-fluidic displays are also very thin and highly deformable.
An innovative solution for the distribution sector is to use beehive-shaped towers for drones that deliver packages. Their main advantage is that they can be built in urban areas with a high population density. These centers would be akin to hubs for trucks and ships that deliver packages, and would probably include a self-service area where customers can go get their packages personally.
