Seawater desalination by wind and solar energy

In some areas of the world, scientists are studying seawater desalination technology due to wind and solar energy, to address freshwater scarcity.

Desalination in seawater with nano membranes

Since ancient times, sailors used to boil sea water and use sponges to get fresh water from steam. Today, the technology of seawater treatment is more modern, but the problem of consuming too much energy for desalination has not been thoroughly solved. 70% of the Earth is covered by water, but humans only exploit 1% of liquid freshwater to meet their daily needs.

Saudi Arabia and rich oil countries have spent a lot of money to filter seawater. However, increasing demand for water, population growth and industrialization and climate change are making water supply increasingly scarce. Petroleum countries, whose economies are mainly based on crude oil sales, are reluctant to use oil to cook water.

Therefore, they and some other countries in the water shortage area are aiming to use solar energy for desalination. "The desalination process requires a lot of energy, so the key is to choose which source of energy," said Aaron Mandell, co-founder and president of WaterFX renewable energy company.

Here are four places that are trying to turn seawater and brackish water into a water source, with the help of wind and solar energy.

Scientists hope that advanced desalination technology can turn saltwater into a potable water source, addressing scarcity in many parts of the world.(Artwork: inquirer.net)

Middle East

In the United Arab Emirates (UAE), four desalination pilot plants will be built in the near future, testing the technology of four companies, in order to find the most energy-efficient option. By mid-2016, Masdar Energy will choose one of the four systems.

In this area, per capita clean water use rate is only 1/7 of the world average and scarcity continues to occur. Experts predict that climate change can reduce rainfall and fresh water by up to 40% by 2050. The World Bank calls on the Middle East to take advantage of the huge potential of the solar energy here. . Every year, solar radiation on every km2 is equal to that obtained by burning 1-2 million barrels of oil.

Australia

Solar desalination technology has made a big advance in this country. Last month, investor KKR announced it was investing in a project of Sundrop Farms, using solar energy to turn seawater into fresh water, for agricultural irrigation. This system produces heat to grow plants in special greenhouses, in an area in southern Australia, where it cannot be cultivated.

"We can grow food crops in dry land that cannot be cultivated or lack of irrigation water. The issue of domestic food security is a major concern," said Philipp Saumweber, head of Sundrop Farms. to speak.

Sundrop and KKR plan to develop a technology center in southern Australia, commercializing products in areas where water shortages or extreme weather problems are also encountered.

Texas State (USA)

Over the years, Texas has intended to exploit the Gulf of Mexico to address the domestic water crisis. After 2011, when the state experienced a bad drought, the interest in this idea grew.

Texas has about 100 seawater desalination plants, which use underground brackish water, but they take energy from coal and natural gas electricity. According to Kate Zerrenner, project manager of the Environmental Protection Fund, instead of increasing the carbon footprint of the water purification process using fossil fuels, Texas should focus on renewable energy.

Texas is leading the nation in wind power technology, accounting for about 20% of America's installed capacity. With many aquifers, water purification uses turbines more easily. However, the filter in the system must operate under stable pressure, while the wind is unstable.

Zerrenner said that it is necessary to integrate the solar system to make operation more stable.

The $ 1 billion Poseidon Water desalination project will be the largest desalination project in the western hemisphere.(Photo: AP)

California State (USA)

Amidst the worst drought in California history, many argue that it is advisable to build factories along the coast, using natural gas. The $ 1 billion Poseidon Water project is under construction in the city of Carlsbad, aiming to become the largest hemisphere water purification plant in the Western Hemisphere.

Mandell, president of the renewable energy company WaterFX, said in the inland areas of the state, the use of solar thermal systems would completely change the desalination industry. It can produce water at half the cost of Poseidon, because the parabolic bridge system will directly convert 100% of the solar radiation into heat to distill saltwater. In principle, this is the modern version for the ancient sailor's method.

"We hope people will follow and improve this model. We have the belief that the best way to have a stable water supply in California is to use the Sun for desalination.", Mandell said