All natural? These fracking byproducts could fight water scarcity
One of the biggest freshwater reservoirs in the world is, literally, up in the air.
Between 6 and 18 million gallons of freshwater hover above every square mile of land, not counting droplets trapped in clouds. Scientists realized this centuries ago but they never have quite figured out how to bring the water down to earth. The effort required to condense it would consume such vast quantities of energy that it always has appeared to make any effort to capture and use this water uneconomical.
But while studying this topic, two of my University of Texas at Austin colleagues and I came up with a concept that might just work: that of using the natural gas that is otherwise flared from oilfields to harvest atmospheric moisture.
We haven’t given it a try yet but we believe it has the potential to be practical and economically viable, especially as water gets scarcer and more expensive. What’s more, the latest research about the extent of natural gas methane leaks and greenhouse gas emissions underscore why it is important to give this technology a shot.
Let there be water
Here’s how the process would work. Excess gas that otherwise would go to waste could power an engine of a big refrigeration unit. This industrial-scale refrigerator would swallow lots of humid air, condensing this moisture into water much like how the air conditioning systems operate in office and residential buildings.
The amount of water that could be collected would depend on the quantity of natural gas available, the weather and the refrigeration system’s efficiency. We project that for every cubic meter of gas, this process will capture up to 2.3 gallons…
