7/30/2019 Us Powerplant Water Withdrawals

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of the country, where surface water is generally more

plentiful (Figure 3).

Power plants in the West, in contrast, relied heavily

on recirculating systems, as those withdraw much lesswater. Dry-cooled power plants were also more com-

mon in the West, although they accounted for only

4 percent of the regions electricity production.

Average freshwater withdrawal intensities for each

state reected these regional dierences. Intensities were

lowest in western states, while areas of high intensity

were scattered around the East, including in the Great

Lakes states, Missouri, Tennessee, Virginia, and the

Carolinas (Figure 4).

and some types of concentrating solar power plantsall

of which use steam to drive turbineshave water intensi-

ties in the range of nuclear or coal. Some renewable

energy power plants with turbines employ dry cooling,and those require minimal amounts of water.

CoolntechnoloesacossheConyTo some degree, power plant cooling systems match lo-

cal water resources. We found that 86 percent of plants

drawing water from the sea in 2008 used once-through

cooling, taking advantage of their access to an essen-

tially limitless resource. Most inland power plants with

once-through systems were located in the eastern half

FigurE 3. Power Pant Water Withdrawas:East versus West

Water withdrawas in 2008 were much higher east than west

of the ississippi. hat is because pants with once-through

cooingwhich withdraw huge voumes of waterpro-

duced a much arger share of eectricity in the eastern haf of

the country, and because overa eectricity production was

aso higher east of the ississippi. Pants with once-through

cooing were ocated chiey aong the coasts, on the shores

of the reat lakes, and on arge rivers and reservoirs.

Note: Based on median NRL values for the use of both freshwater and seawater.

Cooling ponds may operate as once-through systems, recirculating systems, or a

combination of the two.

0.5

0

1.0

1.5

2.0

Generation (billions of MWh)

East of theMississippi

West of theMississippi

Share of Total Generation

54%30%

13%

2%

Cooling Technologies

Once-through

Cooling pond

Recirculating

Dry-cooled

Withdrawal(millions of gallons/year)