Comment Re:Potential Energy of Water (Score 2, Informative) 242
This has been implemented near Cape Town in South Africa. During the evenings, hen demand for electricity is low, they pump water from a resevoir on the cape flats (i.e. nearly at sea level)(google maps link) up to the top of a nearby mountain (link to it on google maps. Then during the day, when the electricity is needed, they let the water flow back down and power a turbine generating surplus for the grid. I think this was implemented since pretty much all of cape town's electricity is supplied by Koeberg nuclear power station (when the turbines aren't breaking down), and from what i can gather, the electrical output from a nuclear plant is pretty constant and would otherwise be wasted if there was not some way to temporarily store it during quiet times for use in peak times.
Actually, I was once speaking to a farmer who owns the farm that the upper resevoir is located next to, and he pointed out a large many-story high concrete pillar (you can see it in the google maps link to the upper resevoir i inserted earlier in this post, to the lower right hand corner of the dam). He reckons, and i have no reason to doubt him, that its there to absorb the backward wave of water that is created when the downward flow is shut off each night. The way he explained it was its almost like a super large tidal bore flows back up the pipeline that was drilled through the mountain to the lower reservoir. Supposedly it would spout a column of water about 50 meters into the air otherwise. Anyway,thats totally irrelevant to the article, just thought it would make the links a bit more interesting.
Actually, I was once speaking to a farmer who owns the farm that the upper resevoir is located next to, and he pointed out a large many-story high concrete pillar (you can see it in the google maps link to the upper resevoir i inserted earlier in this post, to the lower right hand corner of the dam). He reckons, and i have no reason to doubt him, that its there to absorb the backward wave of water that is created when the downward flow is shut off each night. The way he explained it was its almost like a super large tidal bore flows back up the pipeline that was drilled through the mountain to the lower reservoir. Supposedly it would spout a column of water about 50 meters into the air otherwise. Anyway,thats totally irrelevant to the article, just thought it would make the links a bit more interesting.
