drilling costs to plummet, page-3

I would not get too carried away with this "new" cheap drilling. It is purely a slim hole drill design, the hook load capacities are not great enough for any "proper" sized casing strings.

It maybe useful for exploration work for determining bottom hole temperatures, permabilities and flow rates, but for geothermal energy production large heavy casing sizes are required to support high pressures and massive flow rates to make the heat resourse economic, and there is no getting around large diameter pipe and large hook loads.

From what I see, drill bit design has been bought and paid for by the oil industry, where the majority of formations are realatively soft. The Poly Diamond Crystal (PDC) was the major break through in the 1980's that allowed these softer formations to be drilled like a hot knife through butter. They really do not do well in very hard formation, as one of photos PTR released, testifes.

This leaves us with the old tri-cone bit that has was developed by Mr Howard Hughes back in the 1920's, though modern materials have added to its abilities and longevity down hole.

Very hard formations are just very hard to drill, and as GDY found out if you try to take short cuts, as in managed pressure drilling, you had better know what you are doing or you will loose the well. 100 bbl plus kicks are just not acceptable. In business or nature.