Its pretty hard to put a number on it, but firstly they could get some cash out of it and secondly when the frenzy breaks (which i think it will once GDY puts in its 5mw test plant) you need to be able to be identified as a geothermal player to attract investment dollars.
I think the stock and its prospects are completely off the radar. Iress doesnt even mention anything about any of the geothermal exploration done or its tenemants.