Let’s start with a quote from the spring issue of Catalyst magazine: “Take the average amount of water flowing over Niagara Falls in a minute. Now triple it. That’s almost how much water U.S. power plants take in for cooling purposes every minute, on average. (If you have never seen Niagara, that’s a lot of H2O. Here, take a live look at the part known as Horseshoe Falls: http://www.niagarafallslive.com/niagara_falls_webcam.htm. The other part of Niagara is American Falls.) At the same time, water demand is increasing and heat waves and drought are compounding the strain placed on vital freshwater supplies – a problem that global warming is projected to worsen.”
The article is written by Climate and Energy Program analysts at the Union of Concerned Scientists (UCS). In a nutshell, what it says is that our ever-increasing demand for electricity is stressing America’s fresh water supplies. Plants that burn fuel and use that heat to create steam, which in turn spin turbines to produce electricity, need water to boil and/or to cool the plants. But fresh water is not a limitless commodity. Tens of billions of gallons of water come from rivers, lakes, streams and aquifers. Much of that water is lost to evaporation. Almost half of the country’s electric power comes from coal. Coal sucks up two-thirds of that water. It also consumes (evaporation) two-thirds of the water lost to power generation.
A watershed is the area of land where all of the water that is under it or drains off of it goes into the same place. It is where much of humanity derives its water supplies. When we add municipal, agricultural and power plant demand together, 400 of the country’s 2,106 watersheds (in 2008) experienced water supply stress; the point at which demand for water exceeds a critical threshold of the available supply.
Think about this. The water that leaves power plants and is returned to its sources is considerably warmer than the water that left those same sites. That’s because the water was used to cool the plants. And if the water is warm enough, it can devastate fish and other wildlife.
Here is the good news. Some states, on average, do a much better job of managing water stresses than others. That means, within certain bounds, that there are ways of reducing power plant impacts. For example, plants in Michigan, Missouri, North Carolina and Virginia withdrew 40 to 55 times as much freshwater as those in California, Nevada and Utah.
UCS makes five recommendations for reducing power demands’ impacts on fresh water supplies:
- Plans for new generating plants should aim for low-water options including air-cooled (using fans for cooling) wind and solar. The latter two, however, have their own environmental drawbacks, including impacts on birds and wilderness wildlife, respectively.
- Owners and operators of existing plants in water-stressed areas could consider retrofitting to low-water-use cooling. Plant Yates in Georgia added cooling towers, cutting water withdrawals by 93 percent and eliminating large fish kills. Harrington Station in Amarillo, Texas switched to treated wastewater cooling.
- Engage a variety of stakeholders in power generation decisions. Fishermen, water resource managers, and mayors can all have input that leads to better outcomes for their constituents.
- Reduce power plant carbon emissions. Carbon dioxide in the atmosphere increases greenhouse effects which alter climates. Increased heat, changing rain patterns, and droughts could have devastating effects.
Research shows that water temperatures are rising in many lakes, streams and rivers. This makes water-cooled plants work even harder and use more water for cooling. And while adding cooling towers to coal plants, for example, reduces water use, it does not reduce carbon emissions.
We feel, however, that UCS’s recommendations fall short. Once again, no one is talking about the elephant in the room. And it’s one mammoth pachyderm. That would be us humans. Our existence on this earth is what’s screwing everything up. But so few are willing to discuss it, either on a personal, political or societal level. When it comes to reproduction we need to cut back or cut it out. As we continue to proliferate and as we become addicted to gadgets, gizmos and garbage that suck power like electronic vampires, we are rushing headlong into an environmental future for which yet-unborn generations will pay the price. There are, after all, enough of us.