Stories
Slash Boxes
Comments

SoylentNews is people

posted by CoolHand on Friday July 12 2019, @04:02PM   Printer-friendly
from the two-for-one-deal dept.

Submitted via IRC for AndyTheAbsurd

Clean energy and clean water are among the major challenges for sustainable development especially in emerging countries. But traditional approaches to electricity generation consume huge amounts of water. In the US and Europe about 50% of water withdrawals are for energy production.

Similarly, producing water for humans via desalination in countries with water scarcity is a huge consumer of energy. It's estimated that in Arab countries around 15% of electricity production is used to produce drinking water.

Now, researchers believe they have found a way to combine these actions in a single device.

Existing state-of-the-art solar panels face physical limits on the amount of sunlight they can actually turn into electricity. Normally about 10-20% of the sun that hits the panel becomes power. The rest of this heat is considered as waste.

In this experiment, the scientists designed a three stage membrane distillation unit and attached it to the back of the photovoltaic (PV) panel.

The membrane essentially evaporates seawater at relatively low temperatures. The researchers were able to produce three times more water than conventional solar stills while also generating electricity with an efficiency greater than 11%. This meant the device was generating nine times more power than had been achieved in previously published research.

"The waste heat from PV panels has really been ignored, no one has thought about it as a resource," said lead author Prof Peng Wang from King Abdullah University of Science and Technology in Saudi Arabia.

"We use the heat to generate water vapour that gets transported across the membrane and then it condenses on the other side."

Source: https://www.bbc.com/news/science-environment-48910569


Original Submission

 
This discussion has been archived. No new comments can be posted.
Display Options Threshold/Breakthrough Mark All as Read Mark All as Unread
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
  • (Score: 4, Insightful) by Nuke on Friday July 12 2019, @07:31PM (1 child)

    by Nuke (3162) on Friday July 12 2019, @07:31PM (#866364)

    As a power station engineer I'm at a loss to know what I am supposed to have done with 50% of Europe's water. Riverside power stations do take in a lot of water for cooling, but almost all of it goes back into the river again, just a bit warmer than before. Power stations by the sea use sea water in the same way.

    Starting Score:    1  point
    Moderation   +2  
       Insightful=2, Total=2
    Extra 'Insightful' Modifier   0  
    Karma-Bonus Modifier   +1  

    Total Score:   4  
  • (Score: 1, Interesting) by Anonymous Coward on Friday July 12 2019, @08:04PM

    by Anonymous Coward on Friday July 12 2019, @08:04PM (#866373)

    They presumably got their numbers from these statistics [usgs.gov] published by the US government, and then they are (possibly deliberately) conflating two very different terms: water withdrawals versus water consumption.

    It is a withdrawal if you pump water out of a lake and then put it back 5 minutes later, but that's not consumption because the water returned is available to be used again.

    Even with all the misleading, "about 50% of water withdrawals" is still stretching the truth! You only get close to that figure if you consider surface freshwater withdrawals alone and ignore all other water sources used for thermoelectric generation!