Henry Brean observes that Hoover Dam’s ability to generate electricity is down 20 percent with low lake levels, a reminder of the tight integration of water and power questions along the Colorado River. The history of the big dams on the Colorado River, and the question of who gets their water, is inextricably linked with questions of who gets the power.
In a sort of a policy-based perpetual motion machine, a lot of the power generated by the dams’ big hydro plants is used to pump water uphill to farms and cities – down through the dam, then up again through big pumping plants to Phoenix and LA. Only, like most perpetual motion machines, the durn thing didn’t really work when they were building the last link in this chain, the Central Arizona Project. So they built a big coal plant instead which, as Shaun McKinnon recently reported, has turned out to be somewhat problematic.
Anyway, back to Brean, who notes that technology will save us, at least a little bit, with upgrades underway at Hoover Dam aimed at generating more electricity (which we seem to need) with less water (which seems to be what reality dictates in the long run):
The dam’s power customers plan to spend millions of dollars in the coming years to squeeze more electricity from the same amount of water and compensate for a loss of power capacity as a result of the shrinking lake.
The surface of the reservoir dropped 120 feet in the last decade, as the Colorado River came under the grip of the worst drought on record. The resulting loss of water pressure — known as power head — has reduced the dam’s power generating capacity by 20 percent.
The dam and its power customers can’t do anything about the lake level so they are trying to squeeze as much power as possible out of the water pressure they do have.