Wind power is very topical at the moment, following the recent visit to South Africa of a Danish representative punting this means of electricity generation.
Much is being written about wind and solar power, but it would seem to me that there is no coherent plan to put the two together. Wind power only produces electricity when the wind blows. This is about 15% of the time. Denmark has an arrangement with Norway and Germany to supply electricity during the 85% of the time when there is not enough wind to turn its turbines. Similarly, solar power is produced only when the sun shines.
A new pump storage scheme is expected to come on stream in Tubatse in Mpumalanga in about 2014. These schemes operate by pumping water from one dam to another dam at a higher altitude and then letting the water run back down to the lower dam via turbines which generate electricity. Such a scheme has been running from the Spionkop dam for some time now. The advantage of these schemes is that the output is beautifully controllable, feeding electricity into the National Grid just when it is wanted during peak demand times.
It would seem to make a lot of sense to erect wind power turbines and solar power installations very close to these pump storage facilities so that the stop/go power produced by them would not require incur expensive transmission costs, and could be used to pump water instead of being fed directly into the grid - or is that asking too much of inter-departmental cooperation?