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.
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.