Posted by: leothegeo | 2014/02/08

U.S Power Plants’ Rampant Thirst

According to a 2011 report by the Union of Concerned Scientists, the U.S thermoelectric power plants consumed in 2005 as much water as all farms did, and more than four times as much as all people residing in the country.

Some excerpts:

——————————————————————————————————————————————————–

“• Power plants are thirsty.

Every day in 2008, on average, water-cooled thermoelectric power plants in the United States withdrew 60 billion to 170 billion gallons (180,000 to 530,000 acre-feet) of freshwater from rivers, lakes, streams, and aquifers, and consumed 2.8 billion to 5.9 billion gallons (8,600 to 18,100 acre-feet) of that water. Our nation’s large coal fleet alone was responsible for 67 percent of those withdrawals, and 65 percent of that consumption.

Where that water comes from is important.
In the Southwest, where surface water is relatively scarce, power plants withdrew an average of 125 million to190 million gallons (380 to 590 acre-feet) of groundwater daily, tapping many aquifers already suffering from overdraft. By contrast, power plants east of the Mississippi relied overwhelmingly on surface water.
East is not west:
Water intensity varies regionally. Power plant owners can reduce their water intensity the amount of water plants use per unit of electricity generated. Plants in the East generally withdrew more water for each unit of electricity produced than plants in the West, because most have not been fitted with recirculating, dry cooling, or hybrid cooling technologies. Freshwater withdrawal intensity was 41 to 55 times greater in Virginia, North Carolina, Michigan, and Missouri than in Utah, Nevada, and California. Freshwater consumption intensity was similar in those sets of states.
Low-carbon electricity technologies are not necessarily low-water.
On average in 2008, plants in the U.S. nuclear fleet withdrew nearly eight times more freshwater than natural gas plants per unit of electricity generated, and 11 percent more than coal plants. The water intensity of renewable energy technologies varies. Some concentrating solar power plants consume more water per unit of electricity than the average coal plant, while wind farms use essentially no water.
Power plants across the country contribute to water-supply stress.
Based on our analysis, in 2008, 400 out of 2,106 watersheds across the country were experiencing water-supply stress. Power plants, by tap ping this overstretched resource for cooling purposes, contributed to water-supply stress in one-fifth of those. We focused on 25 watersheds in 17 states in which power plants were the primary driver of water-supply
stress based on our analysis. Several states including North Carolina, South Carolina, Missouri, and Michigan had more than one of those watersheds, including the Catawba and Seneca Rivers.
• High-temperature water discharges are common.
Peak summer temperatures for return flows from more than 350 power plants across the country exceeded 90°F. Some 14 states prohibit such discharges, which can harm fish and other wildlife.”
——————————————————————————————————————————————————–
Advertisements

Categories

%d bloggers like this: