subtitle: electrifying and decarbonizing the energy sector by drilling deep holes into hot rock
The newsletter in two sentences: Enhanced geothermal is a flexible clean energy resource that can fill the gaps where solar and wind cannot. I interview Gabriel Malek, Chief of Staff at Fervo Energy and Wilson Ricks, PhD Candidate and Member of Princeton University’s Zero-carbon Energy systems Research and Optimization (ZERO) Lab to learn more.
Within circles of techno-optimists and clean energy nerds, it seems like solar, wind, and storage dominate the headlines. Pundits point to solar’s insane learning curve and rapid deployment, but the reality is we’re nowhere near a 100% decarbonized economy. The trend lines are promising, but hiccups are inevitable. We’ve seen this recently with billions of dollars being written down and gigawatts of projects getting canceled in the wind industry. To address intermittency in solar and wind, storage is required. Batteries are often lauded as a promising solution, but there is no such thing as a silver bullet. There are still plenty of unknowns that come with anything complex. Supply chain crunches, geopolitical conflicts, and ethical labor concerns pose significant risk.
Solar and wind will still continue to dominate the renewable energy mix, but different, complementary types of energy are needed. A clean, reliable grid needs both variable energy sources that are at the mercy of Mother Nature and controllable energy sources that can be dispatched on a dime. The intermittent resources fluctuate over time which results in demand changing at a high rate. Therefore, energy sources that can ramp up and down quickly are needed. Nuclear and coal aren’t efficient in this regard, but natural gas and geothermal are. Choosing geothermal over natural gas is a no-brainer for the emissions, but there’s additional benefits as well. Compared to alternatives like solar and storage, geothermal takes up relatively little land and requires few minerals.
The application of the Earth’s natural underground heat for electricity generation has been around for a while. The first geothermal power plant was built in 1904 in Italy and in the US, we’ve had geothermal plants since the 60s. If geothermal has been around for decades, how come it’s not that prevalent today?
A successful geothermal site must have three things: heat, fluid, and permeability. Existing geothermal plants are hydrothermal, meaning they have naturally occurring heat, fluid, and permeability. While it’s nice that little modification is needed to hydrothermal sites, the downside is that they’re geologically rare. There’s only so many places in the world that resemble Old Faithful in Yellowstone.
The next generation of geothermal plants is referred to as enhanced geothermal systems (EGS). An EGS doesn’t come with pre-existing conditions of the three key attributes. With EGS, you pick a location with naturally occurring heat, add your own fluid, and create your own permeability.
Every EGS project starts with site selection. The most promising regions have hotter temperatures at shallower depths because when heat is closer to the surface, you don’t need to drill as deep. So far, most geothermal has been developed near places where we already know it’s very hot. For example, the Ring-of-Fire region which runs along the periphery of the Pacific Ocean and Iceland, where geothermal makes up over 65% of their energy supply. In the US, Utah and Nevada are good candidates and so is anywhere near known hydrothermal sites such as Yellowstone National Park in northwest Wyoming.
However, building geothermal successfully requires more than picking the right spot. Much of the answer to “Why now?” can be attributed to drilling. The ability to drill down and perform hydraulic fracturing changes the game on two of the three key factors, heat and permeability. By being able to drill effectively and create fractures in the rock where fluid can flow, geothermal becomes way more accessible as an energy source. The potential is large. We only need to access 0.1% of the Earth’s heat content to supply our energy needs for 2 million years. In the US, there’s 5 TW of electric generating potential, which is nearly five times the total US generating capacity today.
In theory, geothermal could play a major role in saving the planet, but in reality, we’re still at the very beginning. Like any new and advanced technology, a lot still needs to improve. In the US, geothermal power currently only makes up 0.4% of annual electricity generation. The DOE announced its target of reducing the cost of EGS by 90% to $45 per megawatt hour by 2035. With low penetration rate, high costs, but lots of opportunity, the question is how this all unfold for enhanced geothermal? What kind of talent, capital, and policy is needed to deploy, prove, and scale geothermal?
I initially chose to cover geothermal because of its unique story with the oil & gas industry. For EGS in particular, drilling seems to be the crux of the matter and no easy feat. Fortunately, for decades, one industry has been motivated by trillions of dollars to innovate on drilling technology. The narrative that critical drilling innovation will be borrowed and repurposed from the oil & gas industry is compelling to me. Much of what you read online paints the oil & gas industry as the main culprit in the climate crisis and rightly so. But what gets lost in the message is that not everyone and not every aspect of the industry is evil. There’s a lot of Houstonians employed at ExxonMobil, Chevron, and Shell that simply want to support their families and don’t actually want to burn the planet down. One oversimplification I observe with the transition of fossil fuel jobs to clean energy jobs is assuming that a coal plant worker can magically switch to becoming an electrician. It’s not a 1:1 shift. Perhaps there’s a more easeful transition that can be made from oil well driller to geothermal well driller. And maybe, just maybe, the transition to a decarbonized energy sector will involve a massive transfer of talent, capital, and drilling expertise from oil & gas to geothermal.
Gabriel Malek is Chief of Staff at Fervo Energy, a startup building enhanced geothermal systems. In November 2023, Fervo unveiled its first-of-its-kind power plant in Nevada which powers Google’s data centers there. In August 2022, Fervo raised $138M in funding led by DCVC. Gabriel began his career at Environmental Defense Fund and then went on to serve as Deputy Chief of Staff for Mark Carney, UN Special Envoy on Climate Action and Finance.
Wilson Ricks is a Mechanical & Aerospace Engineering PhD Candidate and a Member of the Zero-carbon Energy systems Research and Optimization (ZERO) Lab at Princeton University. His current focus is on evaluation of emerging clean energy technologies and energy policy design. Wilson has also interned with the U.S. Department of Energy and Breakthrough Energy.
The rest of this newsletter includes responses from my interviews with Gabe and Wilson. Together, we discuss: