The tech response to global water scarcity

IEC

From water desalination to atmospheric harvesting and floating solar panels, the IEC provides the standards which help water preservation and extraction techniques meet the targets of the United Nations Sustainable Development Goal (SDG) 6.

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With one thousand children under the age of five dying each day in Africa because of the lack of safe water and with populations living in urban areas facing water shortages, the risk of a global water crisis is imminent. While the poorest nations bear the brunt of the suffering, the gap between global water supply and demand is projected to reach 40% by 2030 if current practices continue, warned the World Economic Forum, which called water scarcity one of the greatest challenges of our time.

The UN has urged members to speed up implementation of the UN-Water SDG 6 Global Acceleration Framework warning that “business as usual will not achieve that goal”.  The SDG 6 framework states that water-related challenges require the rapid development and deployment of innovative and transformative ideas. These approaches include water extraction and preservation techniques and the extensive use of IT and AI to help communities optimize water resources and minimize the environmental impact of water use. 

Seawater desalination plants switch to renewables

Desalination is an established technique that pumps water at high pressure through membranes to remove salt and other chemicals from the sea or brackish river water but is increasingly controversial, mostly for environmental reasons. There are environmental concerns about the impact of desalination on ocean life when sea water is sucked into the process and there are also worries about the hypersaline brine discharged at the end. Equally concerning for the health of the planet is that the reverse osmosis process used in most industrial desalination efforts is energy intensive.

However, green energy is increasingly powering such systems. In California, a state prone to drought, the Doheny Ocean Desalination Project will provide 5 million gallons of drinking water for 40 000 people a day by 2028. It aims to power around 15% of its output with solar panels and will integrate an energy recovery process resulting in what it claims is “45% to 55% less energy usage” than a system without that feature.

A desalination plant in Oman aims to be among the first facilities in the Middle East to be powered by renewable electricity. It will switch part of its energy generation to a solar photovoltaic (PV) farm this autumn. Installed in partnership with a French energy firm, the PV modules will power a third of its daily energy consumption.

Tech breakthroughs

Making membranes uniform in density could vastly improve the efficiency of desalinisation, researchers have found. Membranes with “uniform density at the nanoscale” boosted efficiency in tests by 40%, meaning they can clean more water while using significantly less energy.

Another breakthrough has been made by researchers at MIT. Their prototype for a portable desalination device uses an ion concentration polarization (ICP) electrical field generated by a small solar panel to purify water. Rather than filtering water, the ICP process applies an electrical field to membranes placed above and below a channel of water. The membranes repel positively or negatively charged particles – including salt molecules, bacteria and viruses – as they flow past. The charged particles are funnelled into a second stream of water that is eventually discharged (read more about this research in: From seawater to drinking water, with the push of a button  MIT News | Massachusetts Institute of Technology). The suitcase-sized device, which requires less power to operate than a cell phone charger, is intended for deployment in remote and severely resource-limited areas, such as communities on small islands.

The key role of IEC Standards and certification

Traditional desalination plants require pumps, electric motors, valves and scrapers to function. As they are critical assets, they also need supervisory control and data acquisition (SCADA) systems which incorporate cyber security control features.

IEC International Standards provide key safety and performance benchmarks in many of these areas. For example, all fresh and wastewater electric pumps are driven by electric motors most of which comply with the IEC 60034 series of international standards.

The IEC also runs four conformity assessment systems, one of which has direct relevance to the energy efficiency of motors. IECEE, the IEC System of Conformity Assessment Schemes for Electrotechnical Equipment and Components runs the IECEE Global Motor Energy Efficiency Programme (GMEEP). The programme tests motors in relation to the IEC 60034-2-1 Standard.

The IEC 60534 series of standards, which is developed by IEC Subcommittee 65B, provides the technical foundation for pneumatic actuating control valves with electronic positioners. It is considered the bible for the water purification and wastewater treatment industry.

Most pumping stations are automated, and many electronic devices are used for their control and supervision. Programmable logic controllers and remote terminal units are used and integrated in centralized control rooms with SCADA systems. IEC TC 57 publishes the SCADA standards, for example IEC 62361-2. IEC TC 65 develops the IEC 62443 series, which include the relevant cyber security standards.

Harvesting atmospheric water

Atmospheric water, which is present regardless of geographical and hydrologic conditions, is emerging as an alternative water resource. The earth’s atmosphere holds water in the form of droplets or vapour, accounting for up to 10% of freshwater sources and providing around 50 000 km3 water according to researchers. Additionally, the natural hydrologic cycle enables a sustainable water supply. If water can be harvested in arid and remote areas, the challenges of long-distance transport or delivery of potable water could be addressed.

However, there are other issues, particularly in regions where humidity is less than 70%, requiring a substantial amount of energy to condense the vapour. A recent trial in the Death Valley desert used a metal-organic framework powered solely using ambient sunlight to absorb atmospheric water vapour. What’s significant is that the research team’s harvester extracted water without generating any carbon footprint even in extremely hot and dry weather conditions, with an average night humidity of 14%. This process has emerged as a most promising method of water extraction.

Floating PV panels

Increased demand for solar-generated electricity to replace fossil fuels could also help save water. Less than one per cent of the world’s solar installations are currently floating on inland sites like reservoirs. If more floating photovoltaics (FPV) were installed, they could prevent water loss from evaporation.

According to a study published in the journal Nature, 6 256 communities and/or cities in 124 countries, including 154 metropolises, could be self-sufficient with local FPV plants. Doing so would save enough water to supply 300 million people per year. A 2021 study found that floating solar panels on a reservoir in Jordan, one of the world's most water-scarce countries, reduced evaporation by 42%, while producing 425 MWh of electricity annually.

IEC TC 82 prepares international standards for solar PV systems, for example IEC 61701 which specifies testing for salt mist corrosion, which concerns PV modules situated in a marine environment. One of its working groups is preparing a technical report, which is to provide guidelines for safe, reliable and well-performing floating solar systems.

Smart water management

The water industry is beginning to accelerate digital transformation to improve water management practices. Increasingly referred to as ‘smart water management’ or just ‘digital water’, such systems rely on sensors to control water flow, pressure, temperature and liquid levels.

An Indian-based company produces a smart metering and automated leakage prevention system, which has been used on apartment buildings in the country. The device is claimed to have helped reduce overall water consumption by up to 35%, saving precious groundwater and providing affordable electricity associated with the supply of water.

On a larger scale, water utility operators are using virtual replicas of water infrastructure networks to model and respond to issues in real time. These digital twins collect data from underground SCADA systems, sensors and meters, as well as information about when a pipe was installed and the material it's made from, to quickly identify a leak or failure. Digital twins also facilitate continuous monitoring of water systems, detecting weak areas and resolving problems before they become catastrophic failures. 

ISO/IEC JTC 1/SC 41, the IEC and ISO subcommittee standardizing the Internet of Things and Digital Twin, is working on several standards which are expected to facilitate the use of digital twins in many different areas. A priority is to publish a standard on the reference architecture for digital twins. 

In Jackson, Mississippi, where leaks plagued the system for years, engineers have digitally mapped the city’s 100 square miles of water infrastructure and created a virtual model with live data to monitor flow and pressure, providing an uninterrupted water service, and improving water quality for the city’s 150 000 residents. The IEC Smart Cities Systems Committee (SyC Smart Cities) is working on a standard for water management which focuses on the collection and analysis of use cases to identify standard requirements.

The SyC experts recognize that “water is undoubtedly one of the most critical resources for urban development and is therefore a crucial ingredient for the overall common city goals characterized by sustainable development, efficiency, resilience and safety”.