It sounds like they didn't intend to drill into magma, but is it possible to survey the land and intentionally find magma near the surface to exploit in this manner?
If not, isn't the question of whether you can effectively harness the energy or not moot?
I see what you are saying, if you can't find it, why do we care?
Two reasons, as the article states, it has been found, twice in fact. Once in Hawaii and now in Iceland. The Icelandic team is drilling another hole near the existing hole to investigate further. Maybe the same can be done in Hawaii.
The other reason we care is that perhaps technology doesn't exist yet to easily find these near surface reservoirs, but maybe it will in the future. If they determine this hole can be utilized, it will drive research into finding these reservoirs.
I think that there is probably some catch up that surveying needs to do to make this more practical, but it's probably more an effect of not having wanted to find magma before. A quick Google search turns up the following page about remote sensing for volcanic activity.
If there's money in finding magma, research will follow. 36 - 50 MW of non-carbon energy is good news. Geothermal is already competitive with coal (http://en.wikipedia.org/wiki/Cost_of_electricity_by_source#U...) and with recent improvements in drilling technology, magma is within reach. The borehole mentioned above had a depth of 2,100 m. Deepwater Horizon drilled to more than 10,000 m (http://en.wikipedia.org/wiki/Deepwater_Horizon).
Not going to say its easy. But you can pretty accurately map magma under the surface using seismology. I believe it requires an earthquake and having the correct equipment in place, so its far from ideal. But it does work well.
It's really easy! Seismic surveys are key to the oil & gas industry, and can be used for other resources as well. We use thumper trucks instead of waiting for earthquakes.
It's been awhile since I've sat in on geology, but I seem to recall that they can use short-range seismic signals (by firing a shotgun shell into the ground). I'm not sure as to the resolution -- one could imagine getting better resolution firing multiple shells simultaneously over a certain area. My $.02
"39 explosions for the purpose of geological exploration (trying to find new natural gas deposits by studying seismic waves produced by small nuclear explosions)"
If not, isn't the question of whether you can effectively harness the energy or not moot?