Iceland's Krafla magma well produced 450°C steam, record 36 MW potential

August 23, 2026 at 02:30 PM2 min

This digest was compiled by AI from multiple sources — links to the originals are below.

In 2009, a drill crew at Iceland's Krafla caldera accidentally struck magma at 2.1 km depth, reaching 900°C. The well, IDDP-1, later produced superheated steam above 450°C at 140 bar, the hottest production well ever measured. Flow tests indicated it could generate up to 36 MW of electricity, five to ten times a typical geothermal well.

Key Facts

The IDDP-1 well at Krafla produced superheated steam above 450°C at 140 bar wellhead pressure, the hottest production well ever measured.
Flow tests indicated IDDP-1 could generate up to 36 MW of electricity, five to ten times a typical commercial geothermal well.
The drill bit struck magma at just over 2 km depth, with molten rock at around 900°C.
Landsvirkjun, Iceland's national power company, and partners in the Iceland Deep Drilling Project decided to keep the well open after the magma strike.
Corrosion from acid gas, sulphur, and silica dust caused most of the damage to the well.

Accidental Magma Strike

In 2009, a drill crew at Krafla, a volcanic caldera about ten kilometres wide in northeast Iceland, was drilling for supercritical water at over four kilometres depth. At just over two kilometres, the rock returning up the drill pipe turned to fresh volcanic glass, indicating the bit had punched into magma at around 900°C. Drilling into magma is the one thing geothermal engineers are trained never to do. Only one well anywhere had ever struck magma before, in Hawaii in 2007.

Record-Setting Well Performance

Landsvirkjun and its partners in the Iceland Deep Drilling Project decided to keep the hole open and installed a perforated steel casing cemented near the magma. After months of slow reheating, the well produced superheated steam above 450°C at around 140 bar wellhead pressure. Wilfred Elders, a University of California geologist, called IDDP-1 the first magma-enhanced geothermal system on Earth. The Clean Air Task Force noted that IDDP-1 could have generated up to 36 megawatts of electricity, five to ten times a typical commercial well. Björn Þór Guðmundsson, chief executive of the Krafla Magma Testbed, put the same well at ten times the output of an average geothermal well across nearly two years of intermittent flow testing.

Corrosion and Well Failure

Corrosion did most of the damage to the well. Acid gas, sulphur, and silica dust travelled up with the steam.