Advances in geothermal drilling technology: reducing cost while improving longevity of the well

Construction technology and durability of geothermal wells have significantly
improved in the last 30 years resulting in wells that both cost less and have longer
mean times to failure. In developed geothermal areas, well design and drilling practice
are mature, but drilling problems typically still account for an additional 30% to
the cost of a well. However, new drilling practices and technologies are constantly
being introduced, such as dual-tube reverse-circulation (DTRC) drilling. Some of
these have the potential to reduce geothermal drilling costs even further. Other areas
where drilling technology is evolving include lost-circulation control, drill rigs, and
cementing.