Taiwan is lush and rainy — it receives 102 inches of rain per year, on average. But it is also densely populated, with about 1700 people per square mile. So it is denser than U.S. cities like Chattanooga, Montgomery, Mobile, and Oklahoma City. It is also very industrialized.
Because it is so dense and industrialized, Taiwan has barely enough water, despite how much rainfall it gets. So Taiwan is building a large-scale municipal desalination plant in Hsinchu City, at a cost of $545 million. This will enable it to manufacture more semiconductors, whose production process takes a lot of water:
Taiwan’s water supply mainly relies on reservoirs fed by rainfall. Climate change and extreme hydrological events have disrupted these patterns, posing a significant water security risk to the region. With the expansion of semiconductor factories in the Hsinchu Science Park, the demand for water is set to surge.
“Designed to produce 100,000 cubic meters of quality drinking water per day, the Hsinchu SWRO desalination plant will enhance the stability of the water supply and alleviate water scarcity, benefiting around 1.6 million inhabitants and the semiconductor manufacturing industry in Hsinchu City. Construction is scheduled to begin in July 2024 and is expected to be completed by 2028.
By implementing a compact design, energy-efficient solutions for the treatment process1, and the installation of solar panels, the project will save construction space, minimise material consumption and carbon footprint. In addition, the use of the pigging system for offshore pipe cleaning will help reduce the treatments required and generate less wastewater.
The contractor building the desalination plant in Taiwan is also building one in mainland China in China’s northeastern Shandong province, which is as dense as Taiwan, but has much less rainfall (under 30 inches of rain per year). The plant in Shandong will remove salt from 100 million liters of seawater per day, turning it into fresh water. “This is SUEZ’s largest seawater desalination project in the industrial sector. It is designed to use seawater as a complementary water source for the Wanhua Chemical Group industrial complex. It will save more than 36 million cubic meters of freshwater per year, equivalent to the volume of 14,400 Olympic-sized swimming pools.”
Many counties with low rainfall are now turning seawater into drinking water using big desalination plants, such as Malta, Israel, and the United Arab Emirates. In addition, there are now floating desalination machines that use no electricity, which are “100% mechanically driven”: “Oneka’s floating desalination machines – buoys anchored to the seabed – use a membrane system that is solely powered by the movement of the waves. The buoys absorb energy from passing waves, and covert it into mechanical pumping forces that draw in seawater and push around a quarter of it through the desalination system. The fresh, drinking water is then pumped to land through pipelines, again only using the power provided by the waves.”
Drinking water could also be collected from thin air, especially in places like the island nation of Bahrain that are humid, yet seldom receive rain (Peru’s capital, Lima, also is humid, yet receives little rain):
Cody Friesen, an associate professor of materials science at Arizona State University, has developed a solar-powered hydropanel that can absorb water vapor at high volumes when exposed to sunlight. It is a modern-day twist on an approach been used for centuries to pull water from the atmosphere, such as using trees or nets to “catch” fog in Peru, a practice that dates back to the 1500s and is still being used today….Friesen founded his own company Zero Mass Water in 2014 following his research on solar-powered hydropanels. Today the company is called Source Global, operates in more than 50 countries and has a private valuation of more than $1bn (£800m).
The panels work by using sunlight to power fans that pull air into the device, which contains a desiccant material which absorbs and traps moisture. The water molecules accumulate and are emitted as water vapor as the solar energy raises the temperature of the panel to create a high-humidity gas. This then condenses into a liquid before minerals are added to make it drinkable.
“That’s how we’re able to create water in most places in the world, even when it’s very dry,” says Friesen. “We’re headquartered in Scottsdale, Arizona, which is sub-5% relative humidity in the summer and we’re still making water. It’s a uniquely efficient and low-cost approach that enables us to go places where nobody else can go.”
The air, even in relatively dry climates, can hold a surprising amount of water. The Earth’s atmosphere as a whole contains about six times as much water as the planet’s rivers.
