the benefts of EGS. Ormat, for example, successfully enhanced
the operating geothermal feld at the Desert Peak project by stimulating an injection well that had very low permeability.
“The company injected water into the well in order to open up
the fracture network and increase the well’s injectivity,” he said.
“It worked to the point where they were able to increase the output of the power plant by an additional 1. 7 MW.”
NREL’s involvement in EGS advancement is primarily related to
analysis. Augustine said that based on fndings so far, NREL has
determined that, even with limits on how deep developers can
drill, there is a lot of EGS potential in the U.S. The potential, he
said, is so large that it is almost “more than it’s worth quoting a
He did, however, point to fndings from analysis completed
in 2008 by the U.S. Geological Survey that he believes produced
a “fair” estimate of 500 GW of EGS potential at depths between
three and six kilometers.
Most of that potential in the U.S., he added, is based in the
Other studies have looked at EGS potential down to a depth of
10 kilometers, but Augustine said six kilometers is a more realistic drilling depth — both in terms of technology and cost.
“We can drill at 10 kilometers but it gets expensive,” he said. “Six kilometers is a more realistic cut off
in terms of the ability to drill
that deep and the ability to
drill that deep at a reasonable price.”
GEA Report Takeaways
The GEA’s power production
report found that the global geothermal market currently is at 13. 3 GW of operating capacity in 24 countries,
and planned capacity under
development is 12. 5 GW in 82
countries. In addition, the geothermal market is expected to
reach 18. 4 GW by 2021, and
32 GW by the early 2030s.
That growth, according
to GEA’s Matek, has been
estimated by measuring
increased support for geothermal at the government
level around the world.
He said that countries are
starting to increase their geothermal goals to match the
pledge made by the United
Nations and the International
Renewable Energy Agency for
a fve-fold growth in installed
geothermal capacity by 2030.
In addition, about two dozen
countries have listed geothermal in their Intended
Nationally Determined Contributions as a resource they
expect to tap to comply with
the Paris Agreement. à
Ormat Technologies’ Geothermal Power Plant, Steamboat Spring,
Nevada. Credit: Wikimedia Commons — Rjglewis.