To close this out, look for information on the Tennessee Valley Authority's Racoon Mountain Pumped Storage Facility. Take top off mountain, make reservoir on top, drill shaft down to base of mountain, put generators with discharge to a lower reservoir. Its called a peaking plant. Drain the top reservoir during peak times and produce electricity. Cool thing is, the generators can be reversed and become pumps to pump the water back up the mountain during off peak hours. Without going into how fossil fuel fired generation desires to run at a relatively constant level and has minimum loading requirements below which it cannot stabley operate at, and hey you can't store the power, so they use it off peak. Unlike your house or our bandwidth, within the industry, power costs fluctuate over the course of the day. So they take advantage of it. Closest thing to storing electricity thats possible. Even though pumping consumes more power than the falling water produces, the drastic cost differential over the course of the day makes it economically viable. On the flip side, their reservoirs are not hundreds of gallons, but hundreds of acres. One of the interesting design problems they had to overcome was how to keep the top reservoir from swirling like a bathtub when all the generators were online. And when they open the rather large valves (measured in tens of feet) for the tunnels, the mountain tends to shake. a little, at least when you're in the mountain. Fascinating place to tour. It was about 15 years ago. Don't know if they still do tours, but the geek factor was pretty high if you're into that kind of thing. IIRC, they're somewhere in the vicinity Oak Ridge. We took a bus ride from ORNL to there for a day tour. Eric
-----Original Message----- From: owner-nanog@merit.edu [mailto:owner-nanog@merit.edu]On Behalf Of Vadim Antonov Sent: Tuesday, November 19, 2002 5:15 PM To: blitz Cc: nanog@merit.edu Subject: Re: Even the New York Times withholds the address
Just to keep it off-topic :) The kinetic water-based accumulating stations actually do exist, though they use elevated reservoirs to store the water. The water is pumped up during off-peak hours, and then electricity is generated during peaks. This is not common, though, because most energy sources can be throttled to save fuel, or to accumulate in-flowing water naturally. However, I think we will see more of those accumulating stations augmenting green energy sources (wind, solar, geothermal, tidal) which have erratic performance on shorter time scales, unless things like very large supercapacitors or hydrolizers/fuel cells become a lot cheaper.
In some cases accumulating stations are useful in places remote from any regular power sources because they can minimize energy loss in long transmission lines (it is proportional to current squared, while delivered power is linear to the current).
--vadim
On Tue, 19 Nov 2002, blitz wrote:
One last addition to this idiotic water idea.. since the water doesn't get up there to the reservoir on the roof by itself, add your costs of huge pumps, plus the cost of pumping it up there, and a less than 100% efficiency in converting falling water to electricity. Also, add heating it in the winter to keep it liquid instead of solid, decontamination chemicals (cant have any Leigonella bacillus growing in there in the summer) Its all moot, as the weight factor makes this a non-starter.