I might as well add my two pennies worth. Not only is "rock power" not yet commercial technology - hence the serious questions over the final cost per MWh - but it can also be argued that it isn't sustainable energy.

You can't pull the heat out of the ground faster than the earth can replace it without the well eventually going cold. The earth cannot replace it as fast as we need to extract it to generate commercial quantities of elecricity so at some time you will need to decommission a well and wait (perhaps a 100 years or more) until it heats up again.

Geothermal energy is really more like mining fossil fuels without the CO2. Eventually the heat resource will run out at a particular site and we will need to look for new mines.

To blame the problems with geothermal energy on the lack of drilling rigs is just wrong.. the problem with tapping the energy in Australia is that the rocks concerned are kilometres under ground. As I understand it they are right at the limit, if not beyond, of anything that's been done before. And they have to get usable heat out of it, if they manage to drill to that depth.
Several posts have mentioned molten salt or oil used in a solar furnace arrangement. These systems have been around for years and are better at storing energy than wind, so they may reduce the problem of shadow generation, but only at considerably more expense, and does not eliminate it. One post asserts that such systems have been used for base load power. Sorry don't believe it. If there is a link or a reference then let's have it and I'll check it out.
The heating medium used in such systems has to be carefully tailored so that it is unlikely anything produced by a desalination plant would be usable.. thats a tangential issue anyway..

To blame the problems with geothermal energy on the lack of drilling rigs is absolutely correct ..

Oil & big Peabody-coal will NOT tolerate ENERGY competition.

As for HDR installations running-out-of-heat. Such assertions are hypothetical. Only plant running time will sort out those issues not moronic ego-babble. Blanket statements of HDR performance without experiment is UNSCIENTIFIC.

The more likely hypothesis is HDR sites will yield peak performance for a year, then go fallow for several months. Other HDR installations will take-up domestic loads. Then the installations will swap over as heat returns to the fallow site.
This rotation of sites will go on as long as the interior of the earth is molten. That is likely to be about...oh...2to3 billion years.

If you look at a map of global crustal thicknesses, the thinnest spots almost always coincide with curent oil strikes as well as the best HDR sites. Just look at the inordinate crustal thickness around the Saudi oil fields! Old oil wells are prime candidates for new HDR installations. Further, Sth Australia's Flinders Range area at 20Km is significant in this regard both for oil finds and for HDR Geothermal.

All anyone is intelligently capable of saying at this time is that the oil&coal giants have to be dealt with before we can proceed to find out. All the EGO-Babble in the world cannot detract from the potential of HDR Geothermal based on the sheer size of the Earth and its almost limitless Molten core stored energy.

Find out we MUST before the advent of 'forever economic growth' based on the inane notion of 'unrestricted women's Lady Macbeth rights' breeds humanity into THERMODYNAMIC oblivion!

>>Though Peabody Wood be come to Flinders Range
And thou opposed by no woman born
Else Big oil&coal will unendst rule the World.

>>What is a traitor?

One who swears and lies about big coal&oil.

And must all be hanged that swear and lie so?

Every one, especially HDR.

Who must hang them?

Why the honest-rich.

Then the liars and swearers are fools for there are enow' to beat the honest-rich and hang-up-them!

rstuart: "The Hubert Peak, and the Club of Rome all made their predictions in the 1970's. These predictions proved depressing accurate. In particular The Club of Rome predicted a business as usual approach meant would be hitting resource limits around 2030..2050. Since business did continue how accurate that was. They were a little out as it appears we will start hitting limits in the next decade."

Wow, in la-la land the accuracy of predictions can now be verified prior to the event. Do the bookies let you get away with that one, rstuart?

KAEP, considering that there are only test plants in a few of the comparatively easy geothermal sites overseas and nothing at all tappng into the deep hot rock sites they are trying in Australia I don't see how anyone can be confident about geothermal's future. Nor is it possible to blame the failure to date on supposed shortage of drilling rigs given the immense technical difficulties. In essence, geothermal, if it ever works on any significant scale, is yet another very expensive way to generate power. Not really very threatening to the big energy interests is it?

If we don't find new and cost effective ways of producing energy, we'll just keep making the same mistakes as in the past. Every new idea will have it's critics I guess, but that's human nature. Everyone will be protecting their own areas of interest or pieces of turf, and again that human nature. Ha, I just thought of something, maybe this is too important an issue for humans to negotiate, yes sometimes I wish Aliens existed.