Switching to solar or wind energy could eliminate the majority of freshwater withdrawals required for electricity generation.
Only 3 percent of the Earth’s water is freshwater (not from the sea). And with the majority of the planet’s water reserves frozen in glaciers, only about .8 percent can be tapped for human use. With more than 1 billion people worldwide lacking access to clean water, it’s easy to understand how water is a precious and limited resource.
Nearly 90 percent of electricity in the US is still generated by thermoelectric power plants, according to the EIA. These facilities primarily use fossil fuels such as coal, oil and natural gas to boil water for steam to turn turbines that generate electricity. Because of the large amount of water required, thermoelectric power accounts for 45 percent of total US water withdrawals from lakes, rivers and underground aquifers, which far exceeds public consumption and any other source of water demand.
Carbon capture and sequestration has been suggested as a way to control emissions from fossil fuel power plants. But this technology is itself also water-intensive and would increase the amount of water used by power plants.
To provide electricity for an average US home, a coal-fired plant requires upwards of 199 gallons of freshwater per day. However, electricity generated by renewable sources, like solar panels (PV) and wind turbines, requires virtually no water use.
A new study published in Nature Communications explores how this often overlooked benefit could help alleviate water scarcity and improve food security during a drought. Switching to renewable energy sources can eliminate much of the freshwater withdrawals and conserve billions of gallons of water that can instead be used for food production and human consumption. It can also significantly reduce greenhouse gas emissions.
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