The Complicated Relationship Between Water and Energy

WATER, CONSERVATION OCTOBER 1, 2020

Mixing water and electricity can produce dangerous results. But their vital interconnections and vulnerabilities are even more shocking and less often understood.

When getting or disposing of water is instant and easy, whether through a showerhead, faucet, hose, or toilet, it’s easy to forget that it takes a great deal of energy to get it to us, as well as to heat, cool, and clean it.

We need energy systems for our water and we also need water for our energy systems. Here are some quick facts:

• In the United States, the power sector is responsible for the greatest volume of freshwater withdrawals –nearly half – which is used to cool power plants for electricity generation

• Ninety percent of global electricity is generated by boiling water to create steam that spins turbines. Generating power via fossil fuels is water-intense!

• About 8 percent of global energy generation is used for pumping, treating, and transporting water

• By 2035, global energy consumption is expected to increase by 50 percent, increasing water consumption by 85 percent

According to Dr. Michael Webber, deputy director at the Energy Institute, “most of us don’t realize that we use more water for our light switches and electrical outlets than our faucets and showerheads because the water is used for cooling power plants far away.”

Every type of energy requires a different amount of water to generate electricity. But fossil fuel power plants are the thirstiest. According to the Union of Concerned Scientists, “a typical coal plant with a once-through cooling system withdraws between 70 and 180 billion gallons of water per year and consumes 0.36 to 1.1 billion gallons of that water.” That’s enough water to fill between 105,991 and 272,549 Olympic-sized swimming pools – EVERY YEAR. And there are thousands of coal plants around the world.

By comparison, solar photovoltaic systems and wind turbines consume approximately 0.1 – 14 percent of the water required to generate 1 MWh that a coal plant would use over its lifetime. And wind energy requires virtually no water to operate, with only minimal water for manufacturing and site development.

Reducing our dependence on electricity generated by coal-fired power plants will significantly reduce the greenhouse gases that are released into our atmosphere.

Renewable energy can offer a less carbon intense, clear path forward with fewer greenhouse gas emissions and less wasted water that’s better for our planet and for people.

Sources: “Thirst For Power” by Dr. Michael Webber & USGS