JUDY WOODRUFF: As we reported
President Biden and the European
Union today announced plans
to enable Europe to become less
dependent on Russian oil and gas,
but those efforts will take a lot
more money and time to execute.
For now, the Russian invasion is
raised much larger questions over
our dependence on fossil fuels and the
need to develop cleaner renewable energy.
Science correspondent Miles
O'Brien reports on why geothermal
energy is attracting new interest.
MILES O'BRIEN: There's a lot
of heat beneath our feet, and
that's pretty obvious here,
near the Salton Sea in
California's Imperial Valley.
BILLY THOMAS, Berkshire
Hathaway Energy: These are
really world-renowned mud
pots that occur naturally.
MILES O'BRIEN: Hot water and carbon
dioxide create mini-volcanoes
at the Davis-Schrimpf mud pots.
BILLY THOMAS:
They just come up in different
areas. They all go dormant and
just come up somewhere else.
MILES O'BRIEN: They sit right in
the middle of one of the largest
geothermal generation fields
in the world. It's renewable,
sustainable and carbon-free,
so exploring new ways to tap into
this resource is now a very hot field.
What are we seeing here?
BILLY THOMAS: So, here, we're
looking at some of our production
wells for the Region 1 facility.
MILES O'BRIEN: Billy Thomas is a
senior geoscientist at Berkshire
Hathaway's CalEnergy project. He showed me
some of the 25 wells and 10 power plants
which together generate 345 megawatts,
enough to power more than 300,000 homes.
But, he says, they are only
scratching the subsurface.
BILLY THOMAS: This field is
a perfect example of field
that has a lot of potential.
There's about 5,000 gallons per
minute flowing through here.
MILES O'BRIEN: Geothermal heat comes
from the molten core of our planet,
which, at more than 10,000
degrees Fahrenheit, is as hot
as the surface of the sun.
As the heat radiates
up, it gradually cools.
Here, they drilled wells
between 2,000 feet and two miles
deep, where the temperature is
only about 600 degrees Fahrenheit. Very
salty, very hot water, called brine,
along with steam, race upward. The
steam spins turbines, producing
electricity, and the brine
is injected back into the ground,
where it is reheated by the
earth, replenishing the reservoir.
Is this kind of managed well more
or less infinitely sustainable?
BILLY THOMAS: So, yes, we have had the
benefit here of actually operating for
some of these fields up to 40 years, and
we really have a very robust reservoir,
where we don't see a lot of the decline.
So we really have a good system set in
place right now to really make this a
sustainable renewable baseload energy.
MILES O'BRIEN: Baseload, meaning
24/7/365, steady production that
wind and solar cannot provide.
Geothermal is an emerging dark
horse in the race to a stable
zero-carbon electrical grid,
AMANDA KOLKER, National Renewable Energy
Laboratory: The last couple of decades
have seen about a 25
percent growth worldwide.
MILES O'BRIEN: Geologist Amanda
Kolker is program manager
for geothermal technologies
at the National Renewable Energy
Laboratory in Golden, Colorado.
AMANDA KOLKER: The technology
that we're using today really
hasn't changed substantially.
There have been little, incremental
kind of optimization improvements.
It's a really exciting time, because
we are getting a lot more, I think,
innovative ideas in the geothermal
sector than we have for decades.
JIM TURNER, Controlled Thermal
Resources: So this area is
highly fractured underneath.
MILES O'BRIEN: One of the
surprising innovations,
geothermal wells can also be
a great source of minerals.
JIM TURNER: So, we just drilled two wells.
MILES O'BRIEN: Jim Turner
is chief operating officer
of the U.S. division of Australia-based
Controlled Thermal Resources. He walked me
through the 50-megawatt geothermal
power plant the company is
building in the Imperial Valley.
The salty brine rising from the
wells contains almost the entire
periodic table of elements,
and Turner says the rocketing
demand for electric cars
has made it profitable to
extract and sell lithium.
Do you have any projections on how much
lithium you might be able to produce?
JIM TURNER: We will produce about 20,000
metric tons a year of lithium product.
MILES O'BRIEN: That would be about 8
percent of the current global production,
four times more than
the U.S. provides today.
That's a nice bonus, isn't it?
JIM TURNER: It is. It is a
very good bonus. In the past,
it just didn't have enough value to
warrant the cost of money to develop,
build a plant and operate it to be
able to sell the lithium compounds.
MILES O'BRIEN: The rock beneath is
naturally fractured and permeable.
This is the end of the
famous San Andreas Fault.
AMANDA KOLKER: The types of resources
that you need to produce power are not
available everywhere within drillable
depths. It's just, at this stage,
not economic to produce steam
from extremely deep wells.
MILES O'BRIEN: But that could be changing
at the FORGE project in Utah. Here,
the Department of Energy is
piloting a technique called
Enhanced Geothermal Systems, or EGS.
The plan is to drill two deep
wells into low-permeable hot rock,
fracture the rock in between
the wells to create a reservoir,
and then pump water into
the cracks. It returns to the
surface piping hot. The notion is
making for some strange bedfellows.
Oil and gas industry veterans
are now drilling for hot
rock, instead of black gold.
CINDY TAFF, COO, Sage Geosystems: What we
want to prove is a single well EGS system.
MILES O'BRIEN: Petroleum
engineer Cindy Taff is a 35-year
veteran of the oil business.
Now she is chief operating officer
of Houston-based Sage Geosystems.
The company is hoping to reduce the
cost of EGS. Near McAllen, Texas,
they are testing a single well alternative
for harvesting heat from hot dry rock.
They drill down and then
horizontally, from here fracturing
the sedimentary rock in between.
Cold water is pumped down through the
cracks. Now hot enough to generate power,
the water heads up to the turbine in a
concentric pipe in the very same well.
CINDY TAFF: The oil and gas industry has
fracked in sedimentary rock for years,
and we know how to mitigate induced
seismicity. And, quite frankly,
the rock is so soft, you usually don't get
to induced seismicity in sedimentary rock.
MILES O'BRIEN: Still, the well is
ringed by seismic monitoring sites.
Geothermal fracking has triggered
earthquakes in the past.
This one in South Korea in 2017
made news, causing 135 injuries.
AMANDA KOLKER: We don't need
stimulation for most geothermal.
Where we do, do stimulation,
I think we can be smart about
avoiding zones of seismic risk.
MILES O'BRIEN: The shale fracking
boom has driven a lot of innovation
in the drilling business. In
Houston, a small company called Particle
Drilling is partnering with a big player,
NOV, to help push drilling
technology into a geothermal era.
The bit they are developing
fires 12 million ball bearings
a minute out of four nozzles.
Jim Schiller is CEO of Particle.
JOHN SCHILLER, CEO, Particle Drilling:
It obliterates the rock. What you get
out are some very fine cuttings and
every once in a while a bigger piece.
What we envision was always a
three-to-five-time improvement.
As we have combined our bits between NOV
and Particle and all, we're seeing that.
MILES O'BRIEN: Tony Pink is
chief technology officer of NOV.
He says it costs about $100,000 a
day to run a typical drilling rig.
TONY PINK, Chief Technology Officer, NOV:
We're at that tipping point now. And so,
if we take the particle drilling
technology or drill bit technology
and make that jump from
60 foot an hour to 80 to 100,
then we move that economic needle
that you get geothermal anywhere.
MILES O'BRIEN: Geothermal anywhere,
it's an enticing prospect.
The path to zero carbon may
well take us on a journey
toward the center of the Earth.
For the "PBS NewsHour," I'm
Miles O'Brien in Houston.