Water is the elephant in the room. IDTechEx’s new study, Smart Cities Market 2021-2041: Energy, Food, Water, Materials, Transportation Forecasts, points out that cities increasingly and massively depend on water technology as sea levels rise, and for other reasons. They will eliminate sewage systems by treating it where it is produced. Gone will be thirsty, traditional agriculture systems, and their global supply chains.
Currently, cities are killing the sea that is increasingly near to them. Dead ocean areas are spreading. They do this with untreated sewerage, salt from desalination plants, chemicals from factories, leisure activities, marine vessels, and farm runoff of toxins and fertilizer. Cities must instead farm the sea, maintain biodiversity and create benign marine tourism and leisure activities. Methods of distributing salt from desalination without killing bio-life exist, but deployment is slow.
The report analyses the following trends in water utilisation:
Cities on the sea
Smart cities are planned to be at sea and on reclaimed land as at Forest City Malaysia, which promises a veritable jungle with “sounds of nature” and all that greenery self-watering. You can buy a house on and under the sea in Dubai.
Cities will make all their own food, fresh water, and electricity for reasons of empowerment, security, and cost. That electricity-generation is even pivoting to water with tidal turbines — installed from Scotland to the Hudson River in New York — and wave power, both being almost continuous and using almost none of the steel and concrete that produces 16% of global warming. Tidal turbines and wave power take a few hours to drop them in — not 10 years as for hydro dams.
Part of the reason for water power is that there is less and less land for wind turbines and solar farms. Silicon solar works better when cold, so it is migrating to sea or lakes as ‘floatovoltaics’. New photovoltaic materials are even useful underwater, and photovoltaic paint is on the way, as explained in the IDTechEx report, Materials Opportunities in Emerging Photovoltaics 2020-2040.
Leaders in tidal power such as Simec Atlantis and Verdant Power have more companies chasing them. The same can be said for wave power leaders such as Seabased, Wello, and Eco Wave. ORPC RivGen horizontal axis water turbines are proving viable, even in shallow rivers, and they do not disturb fish. Most water power is virtually continuous – no massive batteries. See the IDTechEx report, Distributed Generation: Off-Grid Zero-Emission kW-MW 2020-2040.
Leisure and freight on water
Cities will focus more on their leisure industry and freight transport to be on the water. See the IDTechEx report, Electric Leisure & Sea-going Boats and Ships 2021-2040.
IDTechEx sees several ways that even large ships can become zero-emission, as compared to the present when they each pollute as much as millions of cars. At the other extreme, Swiss Seabubble aquaplaning water taxis are zero-emission, charged by small river turbines under the landing platform, and are planned for Paris.
Click below to read on about smart agriculture, gardening, water transport and thirsty desert cities in water utilisation trends.
Smart agriculture
Today’s farming systems on land consume large amounts of water and boost global warming. They are planned to be replaced by vertical farming (see the IDTechEx report, Vertical Farming 2020-2030), solar greenhouses, hydroponics in buildings, aquaponics and saline agriculture in marshes as sea levels rise.
Genetic agriculture will save water. See the IDTechEx report, Genetic Technologies in Agriculture 2020-2030: Forecasts, Markets, Technologies.
Meat and milk will be grown in city laboratories, and managing with only 1% of fresh water will become commonplace. See the IDTechEx report, Plant-based and Cultivated Meat 2020-2030.
Soliculture greenhouses on rooftops and elsewhere are adopting smart glass that provides electricity for the robots as well as optimally growing plants again with almost no water. Robotic food cultivation is integrated with human facilities in parts of China, saving space and water. Fish farming and barley, samphire, seaweed, and other vegetable growing in saline water is a practice dating back to the ancient Sumerians, but it is necessarily broadening in scope as global warming and people moving to cities makes land even more scarce. There is a roadmap of many options to go even further. For example, aquaponics uses even less land than hydroponics, and it costs less. Aquaponics is growing fish and vegetables in one closed system, with the fish excrement feeding the plants.
Smart gardening
Some are planning on utilising a turf that produces electricity as well as tapping and filtering rainwater for use. Xeriscaping is appearing in smart cities. It is the practice of creating landscapes that need minimal or no water at all beyond what the environment naturally provides, to reduce or eliminate the need for irrigation with supplemental water. It is promoted in regions that do not have accessible, plentiful, or reliable supplies of fresh water and is gaining acceptance in other regions as access to irrigation water is becoming limited. Xeriscaping is an alternative to various types of traditional gardening in smart cities that are frugal by necessity.
The trend of multi-purposing even extends to damp turf, vegetation, and soil. Plant-e is a company that develops products that can generate electricity from living plants, and Harvard University has biofuel cells using such fuels.
Click below to read on about smart water transport and thirsty desert cities in water utilisation trends.
Smart water transport
Transport systems are being reinvented for smart cities which is necessary. Hyperloop transporting passengers from city to city by magnetic levitation in a vacuum and The Boring Company loop shooting autonomous cars at high speed across cities will increasingly be through tubes in the sea, lake or river for at least part of the way. This transportation method even saves money. Autonomous underwater vehicles are zero-emission and they monitor offshore wind turbines, sea-floor mining, fish stocks, and more. Leisure submarines are a possibility – seeing deployment as taxis too.
Thirsty desert cities
The largest challenge of the $500-billion NEOM smart city in the Saudi Arabian desert is drinking water – all desalinated from the sea. See the IDTechEx report, Desalination: Off Grid Zero Emission 2018-2028.
The Bill Gates Belmont desert city in Arizona is nowhere near the sea, and the state gets its water from the Colorado River, which is drying up. By far its biggest challenge is water. It has to guarantee 100 years’ supply to be allowed to start. Arizona-based startup Zero Mass Water’s SOURCE photovoltaic panels make electricity but also use the sun’s rays to pull water from the air. Each panel has the potential to draw up to 10 litres (2.64 gallons) of water per day. That will help, but all the sources still leave that city with severe water conservation requirements.
One of the conservation requirements Bill Gates has proven from his investments is that the elimination of sewage distribution and treatment farms is possible when it is treated at the source. That saves large amounts of water. One new toilet has an electrochemical reactor that can break down water and human waste into fertilizer for fields and create hydrogen, which can be stored in hydrogen fuel cells as a green energy source. Even the little water used is treated enough to reuse for flushing or for irrigation.