Events of the last few days say a lot about our politics, our planet, and our prospects. When it comes to thinking about our energy-water future, three events in particular stand out: NOAA’s news about 2012 temperatures, Georgia Power’s announcement about power plant retirements, and the renewable energy pieces of Washington’s recent fiscal deal.
Hot Time in the Country
From the perspective of power plant cooling water needs, higher temperatures in 2012 meant that our nation’s steam-producing power plants operated less efficiently, and had to use more water or generate less electricity with the same amount of water.
Along with that record heat, though, came some serious drought for over 60 percent of the country. For power plants, drought means that the water they need is either less available or hotter.
Either way, it spells trouble. And there was trouble aplenty last year, as we’ve documented — for power plants themselves or from the additional pressure that power plants put on the lakes or rivers.
The Role of Coal
So, what can we do about this climate-energy-water connection? Lots, it turns out.
One is to recognize the connection, and to make sure we have good data about where we stand, where we’re headed, and what our choices mean. All of that is a large chunk of the rationale behind UCS’s Energy and Water in a Warming World initiative (EW3).
When you look at the U.S. power plant fleet in terms of that connection, one thing you see is the outsized pressure that coal plants, in particular, put on our nation’s water resources. Our 2011 analysis of power plant water use, for example, calculated that coal plants accounted for 59 percent of freshwater-cooled electricity generation, but 67 percent of freshwater withdrawals and 65 percent of consumption.
Georgia (Power) on my Mind
That makes Georgia Power’s announcement stand out. This week the company says it intends to retire 15 coal- and oil-fired generators, and switch two others to natural gas. Water concerns probably weren’t a big driver for the decision — the company claimed it had to do with EPA regulations, though, as recent UCS analysis made clear, every one of the affected units was “economically vulnerable” because of rock-bottom natural gas prices.
But water will likely be an important outcome of Georgia Power’s decision, at least in the vicinity of the plants. According to our calculations, in one recent year, the generators in question alone (that is, not even the full power plants where they sit) withdrew some 300 billion gallons of water for cooling and consumed (evaporated) six to seven billion gallons of it. The non-consumed part would have gone back, but hotter and maybe with extras in the form of chemicals used in the operation of the plants.
Meanwhile, more efficient combined-cycle plants consume some 70 percent less water than a standard coal plant, even without a change in the cooling technology.
Retiring or retrofitting some of the generators at each of those plants, then, can mean a whole lot less water withdrawal and consumption from the lakes and rivers they sit on. It can also mean much less impact from water the plants dump back in, including from water that’s way too warm.
Congress to the Rescue
Those water improvements, though, depend on the demand for power getting met with low- or no-water resources like energy efficiency, wind turbines, or solar photovoltaics.
Which brings us to one more piece of recent news. Folks in general seemed pretty focused on the what-it-means-for-my-tax-bill implications of last week’s fiscal deal. (Go figure.) But in that same package was an extension of a really important driver for renewable energy development in the U.S.: the production tax credit. That was big news for wind, solar, geothermal, and other renewable energy sources.
From an energy-water perspective, some of those resources are slam dunks — wind and solar photovoltaics, for example, generate electricity without using water (and energy efficiency, which cuts out the electricity generation in the first place). Georgia Power itself is working on developing 200 megawatts of solar power over the next three years under its Advanced Solar Initiative.
Projects based on other, steam-producing renewable energy sources need to (and can) choose the right options to minimize water impacts.
Either way (going back to Story #1 above) moving toward clean energy and away from fossil fuels in the electricity sector is a major way we can get a grip on our carbon problem and its future impact on water resources.
It’s About Choices
So we’re making choices, and some of those are moves in the right direction. Recent events shine a pretty bright light on the importance of planning for a changing climate, and the possibility of making energy sector moves that do something about it, reducing both our energy-water risk and our contribution to climate change.
As our 2011 power plant water use report puts it:
“Decisions made today about which power plants to build, which to retire, and which energy or cooling technologies to deploy and develop matter greatly. Understanding how these choices affect water use and water stress will help ensure that the dependence of power plants on water does not comprise that resource, the plants themselves, or the energy we rely on them to provide.”
Sounds like a plan, for 2013 and far beyond.
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